H OW TO I N STALL

El tric Bells Annunciators ec , ,

and Alar s m .

lN CLUD lN G

rie s Wire s a n d Wir in C irc u its P us/z e s Be lls Ba tte , g, , , ,

Bu r la r A la r m s H i lz a rid L o w Wa te r A l r m s g , g a ,

A n u n cia Fire A l a rms , Tit e r m o s ta ts , n to rs , and til e L oca tio n a n d Re m e dying

T o u ble s of r .

' N O RM AN H SCH N EI DER . ‘ ' “ A uth o r o f Th e St u d o f Ele ct ricit fo r e in n e rs C are and y y B g , " H an dlin o f El e ct ric Plant s e t c g , . , e t c .

SECON Q fidmomfism m ééb

N EW YO RK

SPON CH AMBERLA N 123 LIBER I . TY STREET

LON DO N E F . . N P . S O N . Limite d 57 AYMARKE W , H T. S . 1913 Co pyrigh t 1904

C o pyrigh t 1913

By SPON 8c CHAMBERLAIN

The C ame o t Pre ss 16- 18 Oak St N e w l , PREFACE

Amo ng all the applications of electric ity to d m mm s s fe w w o estic or co ercial u e , are as ide

P c spread as the electric bell . ra tically every build in fo r a w n e m n g used d elli g, storag or a ufacture an e b nn n m requires el ctric ell, a u ciator or alar system . This book was written to explain in practical language h o w an electric b ell system operates an d h o w it is in stalled ; its suc cess show n Iby its large sale has resulted in this new edition which bri ngs s the ubject up to date . M any n e w diagrams o f annunc iator and burglar l m m n w t a ar syste s have bee added , together i h de scriptio ns and illustrations of wiring elevato rs for

“ w n fo r d o n th e electric bells , iri g oor pe ers , use of transform ers for furnishing suitable ringing cur rent from electric light c ircuits ; and high voltage bells i ntended to be used o n other than the cus to m ar lo w y voltage battery circuits . Th e author expresses his acknowledgment to the

' Western Electric Company for diagrams o f door opener c ircuits in connection w ith their interphone to E w r and C n N Y systems , d a ds ompa y of e w ork v fo r m o f alarms b u r lar an d diagra s fire , g alarms o to W s C m annunciat rs , and the estinghou e o pany

fo r o o f - n n n o m illustrati ns bell ri gi g tra sf r ers .

2 6 7 4 9 4

CON TEN TS

I N TRODU CTI ON

I T nc e an e e ct e l n . c b ntro ductio h e p ri ip l of l ri l .

CH APTER I

— — — Th e L e clanch e ce ll Pol ari z ation Se tti ng up Th e — — dry ce ll Th e gravity ce ll Co nn e cting up ce ll s

CH APTER I I

/ — — Th e sin gl e st ro k e b e ll Th e sh u n t be ll Th e diffe re n — — ti al be ll Th e conti n u ou s ri ng b e ll Th e wat e r — — — proof be ll Form s of gongs Th e bu z z e r L ong — — — di stance be ll s Th e re l ay Th e p u sh Thre e p oi nt — — or doubl e contact p u sh Floor p ush Door p ull I ndicating p ush

CH APTER I I I — — Be ll wire s- Joint s Runn i ng wire s H o w to p ut up a d be — C mb nat ns b e s u s e s an d b at oor ll o i io of ll , p h rie s—Fau t s in be s fau ts in w n —H t e l ll , l iri g o w to_ locate and re me dy faults V i CO N TE N TS

CH APTER I V

PAG E — — — Fire al arms Th e rmo stats M e tallic th e rmo stats M e r — cu ry th e rmo stat H o w to conne ct th e rmo stats — — Wate r l e ve l i ndicators Burgl ar al arms Op e n an d c se d c cu t a a m s— W nd w d an d s ade lo ir i l r i o , oor h — — — sp ri ng s Al arm matti ng Yal e lock al arm D 0 0 trip al arm

CH APTER V

— Th e annunciator drop Th e n e e dl e or arrow drop — Th e p e ndul um drop Wiri ng u p annu n ci ators — Re t urn or fire call syste ms D ou bl e w ire sy ste m We ste rn El e ctri c singl e w ire sy ste m 55

CH APTER V I

— Thre e - wire re turn call sy st e m I n stalli ng e l e vator an — — n un ciato rs Burglar al arm ann un ci ators Clo ck — — — alarm circuit Be ll s fo r high vol tage s Be ll rin gi ng t an sf m e s— C m b n at n b e d O e n e an d r or r o i io ll , oor p r — — t e l e p hon e c ircu its Fire al arm circui t i nt e rior fi re — al arm syste m Fire al arm syst e m fo r con side rabl e are as LI ST OF I LLUSTRATI ON S

Fro .

1 ' E e ct c be u s and batte l ri ll , p h , ry 2 L e clan ch e ce ll 3 Dry ce ll 4 Gravity ce ll 5 V ibrat ing b e ll 6 Sin gl e strok e b e ll 7 Shunt or short circuit be ll 8 Conti nu ou s ri ng be ll 9 Wate rp roof b e ll 10 Dome gon g 1 1 Te a gon g 12 Co w gong 13 Sl e igh be ll gong 14 Sp iral gong Re l ay and circuit 16 D oor p u sh 17 Pe ar p ush 18 D oor p u sh 19 Wall p ush 20 Floor p u sh 2 1 D oor p ull attachme nt 22 Wire j oi nt first op e ration 2 3 Wire j oint se cond Op e ration 24 Wire j o int insul ati ng 25 Se ction O f ho use showi ng wiring 26 Be ll with grou nd re turn 2 7 Pushe s in multipl e viii L I ST OF ILLUSTRATION S

FI G . 2 8 Be ll s in se rie s 29 Be ll s in mul tip l e 30 Two be ll s and two p u she s 3 1 Two be ll s an d two p ushe s 32 Two be s two u s e s and o ne batte ll , p h ry 3 3 Doubl e contact p u sh 34 Grounde d be ll 3 5 Tongue te st of wiri ng 3 6 . Kn ife te st Of w iring 37 Kn ife te st of wiri n g 38 M e tallic th e rmo st at 39 M e rcury th e rmo stat 4 0 M e rcu ry th e rmo stat Circu it 4 1 Wate r l e ve l al arm 42 L e ve r wate r l e ve l al arm 4 3 High or lo w w ate r l e ve l al arm 4 4 Win dow sp ri ng for burgl ar al arm — 4 5 Burgl ar al arm clo se d circu it 46 Sp e cial be ll con ne ction for b u rgl ar al arm 4 7 Sp e cial be ll conne ction for burgl ar al arm 4 8 Burgl ar al arm an d re l ay 4 9 Wi ndo w - shade contact sp ri ng 50 Ho use w ire d fo r burgl ar al arm 5 1 D oor trip al arm 52 An nun ci ator drop 53 N e e dl e drop 54 N e e dl e drop i ndi cati ng 55 Pe n dul um drop 56 Annunci ator drop circuit 5 7 Simpl e annunciator circu it 58 Annu nciator and fire call circu it 59 Singl e - wire room and fire call L I ST O F I L L U STRATI O N S

FI ~ G.

60 Th re e - wire re turn call circuit 61 E a b an d ann un a l e v tor e ll s ci tor c ircuit .

’ 62 Bu a a m annun a u rglar l r ci tor circ it . 63 Clock alarm circuit 64 Be ll - ringi ng tran sforme r 65 Be ll - ri ngi n g tran sform e r w ith thre e se con dary voltage s 66 We ste rn El e ctric i nte rp hon e syste m 67 We ste rn El e ctric in te rp hon e syste m for more e x t e n sive se rvice 68 Fire alarm circu it 69 I nte rior fire alarm circu it 70 Fire al arm circu it for con side rabl e are as I N TRODUCTI ON

An electric bell depends for its action on the fact that a piece O f iron wound with insulated wire becomes a magnet and will attract another piece of iron j ust so long as an electric current is allowed to travel through the w ire .

Th e instant the current ceases , the magnetism also ceases , and the attracted piece of iron (termed the armature) is no longer held in contact . Th e general construction of an electric bell

' Fi 1 M o f in su late d . M is shown in g . are coils A wire wound on soft iron cores . is a soft iron armature mounted on a flat sprin g so that h is normally kept a slight distance away from the soft iron cores . 5 is a brass screw with a plat inum tip touching a platinum disc on a spring attached to the armature . W P w hen the push button is pressed do n . its two brass springs touch each other , the current from the battery cell B then flows through the W wire , through the push P , through the M M A in d coils , along to the plat um isc , out I N TRODU CTIO N

F I G. 1 I N TROD U CTIO N

S th at , which touches this disc , and back to e battery . The instant this is done the current causes the A iron cores to become magnets , they attract , S which then breaks contact at . The spring mounting of A causes it to j ump back to its 5 first position , then touches the platinum disc

cu rre n fio ws again , the t as before , and the arma ture is again attracted only to break contact with S and fly back . This continual making and breaking O f the

Ci rcuit keeps up as long as the push is pressed , a

' ball mounted on A b y m e an s O f a rod strikes against the gong G causing a continuous ringi ng

. t of the bell The wires leading be ween the bell , ' battery cell and push must all be insulated , that i s e . , covered with cotton , rubb r , etc , which pre vents the leakage o f current should two wires C w cross each other . opper ire i s mostly used for u circ its indoors , the details of the kind and size f O i . w re will be given later on ‘ Th e main parts of an electric bell Circuit are — then the battery to supply the electric current ; u the circuit , or wires , to carry this current ;a p sh , or circuit breaker , to control the current flow ; and a bell to utilize the current . CH APTER I

Th e Battery

r Th e Batt e y Ce ll . The battery cell most used

L eclanch e in electric bell work is the , or some modification of it .

n h is Fi 2 L e cla c e . The battery cell shown in g ,

4

F I G. 2

J is Z O f P where a glass jar , a rod zinc , and a j ar O f porous earthenware containing a carbon rod surrounded by powdered carbon and peroxide O f manganese . “ E LECTRI C ‘ BE LLS AN D ALARMS

In setting up this cell about four ounces of sal ammoniac (chloride of ammonia ) are put into the jar and enough water added to come about half way up the jar . Th e porous j ar P and the zinc Z are then inserted , and the cell is ready for use in a few minutes after the liquid has soaked through the

- earthenware into the carbon manganese mixture . Water is often poured into the porous j ar through holes in its top to hasten this wetting .

Wires are clamped by nuts or se t - screws to the negative terminal on the zinc or the positive ter

n t minal on the carbon , it generally o being of consequence which terminal is attached to either r wi e of the circuit . A battery cell could be constructed without the

O f manganese , using simply a plate carbon and

O f as a rod zinc , but hydrogen g would be gen crated on the carbon plate when th e cell w as work ing and would stop the current flowing .

This is called polarization , and peroxide of man

- ganese is a de polarizer , because it combines with this hydrogen gas almost as fast as it is generated , and prevents , to a great extent , the polarization .

But it does not stop it entirely , as will be seen if the L e clan ch e cell is kept working above its

capacity . Then the hydrogen is generated too

fast for the manganese to destroy it , and the cell TH E BATTERY 3

ceases to work . In this case a rest will often restore the cell to its former power . Cells which have been almost unable to make a bell give even a single tap have been found good again when allowed to remain at rest over night . In setting up a batterycell no liquid should be splashed on the brass te rn iinals or corrosion will E take place . very metal surface where connec tion is made to allow electric current to pass must

and be clean and bright , all screws , or nuts , hold ing wires must be screwed up tight so that the

firml wires are ygclamped . L oose or di rty connections are the cause O f probably eight out of every ten troubles affecting bells and batteries .

' When the fluid in a L e clan ch e cell becomes

O r milky , more sal ammoniac must be added . ,

O ld better still , throw out the solution , wash the

I n C porous j ar thoroughly lean water , scrape the w zinc bright , and half fill the cell ith fresh solu tion . The zinc wearing away rapidly or becoming

am covered with crystals , and a strong smell of monia , show generally that the cell is being worked too hard , or that the current is leaking where it should not . A zinc rod in a cell working the average door 4 ELECTRIC BELLS A N D ALARMS

be ll fo r should last for six months , the porous jar a year .

r Th e D y C e ll . The L e clan ch e cell being a cell with much free liquid is liable to dry up if Fi . 3 not watched The dry cell ( g. ) is a modern

F I G. 3 form of the L e clanch e where the liquid is held by an absorbent material , such as blotting paper , or plaster . * An A typical dry cell is shown in the figure .

* f o 3 Fo r full de scription O f thi s cl ass O battery se e N . B k “ " oo o n D ry Batte rie s.

D 6, ELECTRIC BELLS A N ALARMS

~ Th e G ravi t D anie l C e . ravitv y l ll The g cell ,

Fi . 4 Z g , has a zinc block suspended from the side of the j ar and a number O f copper leaves C A standing on edge at the bottom . quantity of bluestone (sulphate of copper) is poured over th e copper leaves and the j ar filled w ith w ater .

D l is uring the working of this ce l , copper de

o n posited the copper plate, and sulphate of zinc th T formed at e zinc . O hasten the action a small quantity of zinc sulphate can be added to the n solution when setti g up the cell . " Th e name of this Cell comes from the fact that th e e o fiper solution being heavie r remains at the bottom of the j ar . If the cell is not worked

i th e enough , all the solut on will become blue and

' ' “ ir fr . d t o m zinc will blacken I f very y this cause , remove the zinc , scrape and wash it thoroughly .

h n e w T row out all the solution , add sulphate and c water and replacing the zin , then put the cell on short circuit by' connecting the copper and

r zinc togethe for a few hours .

B M . F. . T f is n h . O e e m . f . a gravity cell withi

- a fraction of one volt , its current nearly one half

' N Varmth amak e s it give a greater current ;on no account let a gravity cell freeze . TH E BATTERY 7

Re sistance o f a Ce ll . The fluids in a cell do not conduct electricity as well as copper do es ;they offer more resistance and th u s . re duce the current output .

Th e internal resistance O f. a cell may be low ered by using large zinc plates curled around the porous pot . Th e Samson cell has a large zinc plate bent in

- the form of a cylinder , the carbon manganese f combination standing in the centre O it .

The dry cell also has a large zinc , the internal resistance being thus much lowered , the current ’ u T O f outp t is increased . his is by reason Ohm s law , which teaches that to increase the current in flow , either the voltage of the battery must be

o r . creased , the resistance decreased But increased current means lessened life ;there is only just SO much energy in a cell mainly de pendent o u the quantity of chemicals .

G o in f r up g O C e ll s. Cells may be grouped in a

am battery to get increased voltage, or increased e ra e W p g . hen connected for the former , they

O f are in series , the carbon one is connected to the

so . zinc of the next , and on If all the carbons are connected together and all the zincs , they are in multiple, and will give the 8 ELECTRIC BELLS A N D ALARMS same voltage as of one cell but the combined am

e ra f p ge O all . In ordinary bell work the series is the general

O f connection , the higher the resistance the cir

is cuit , or the longer the wires , the more voltage required . CH APTER - II

Bells and Push es

E ri B l e ct c e ll s. Th e two main types of house bells are the iron box and the skeleton .

Th e bo x - iron has a cast iron frame , or base , and

- a cast or stamped iron cover over the mechanism . The skeleton bell has an iron frame but no cover , and is generally better finished and more

bo expensive than the iron x bells .

Fo r fire alarm purposes , mechanical bells or gongs are made , in which a clockwork mechan ism causes the hammer to strike the gong upon

e being r leased by electromagnetism . M arine or waterproof bells have an iron cover fitting tight over a rubber gasket ; they are for marine , or mining, work . d e Polarized , or magneto , bells are use in tel

O phone work , and are rarely perated by a battery , but have a miniature dynamo generator operated by hand , or power , to supply the actuating cur rent . M ost bells are classed for size by the diameter — of the gong , a four inch bell being one with a gong four inches in diameter ;a six- inch bell one

-i with a six nch gong , and so on . 1 0 ELECTRIC BELLS A N D ALARMS

According to the use for which they are in tended , bells may be vibrating , as before described ,

- - ff single stroke , shunt or short circuiting , di eren

- O f tial , continuous ringing , or adapted for circuits high voltage .

Th e S in - tr k B gl e s o e e ll . Th e bell before de i F . 5 scribed , and again shown in g , is a vibrating , i . s i or trembling , bell It often des red to have the hammer give only one stroke for each pressure o f

- in si nalin the push , as g g with a code of taps ;in

- is this case a single stroke bell used . The circuit

FI 6 FI G. 7 F G. I G. 5 from the binding posts is then directly through the magnet coils without any break at the contact i 6 F . w . scre , as in g

I n adj usting such a bell to give a clear sound , press the armature up against the iron magnet cores and then bend back the hammer until it j ust clears the gong . The spring of the hammer wire will carry the hammer sufficiently forward to hit th e gong . The tone will be clearer than i f the hammer dampe re d the gong by pressing against it when the armature was nearest the core . " BELLS A N D PUS H E-s I t

B i i Out a i y br ng ng a third connection , vibrat ng

' r k n n bell may be made both single st o e a d vibrati g.

Th h n e S u t Be ll . There is a form o f bell

"

Fi - ow h i i . 7 t e g kn n as shunt , or short c rcu t bell ,

“ which is O ften used wh en two or more are to be

e w de scri connected in s ries , as ill be seen in the p “ u tionof circuits . In this bell the circ it through the magnets is not broken at the contact screw , but the forward movement O ft h e i a‘ rmature short circuits the coils .

‘ ' " ‘ As th e C r t er h short , or shunt , i cui is v y muc

' lower in resistance than the w ire o n the magne t

th e m w t h e a e and coils , ain current flo s around l tt r

Th e fat they do not become ene rgized . sparking the shunting contact screw is much less than it w d a re c e ould be at the or in ry b aking contact s r w , an d the platinum points last longer .

“ n Th e Diffe re tial Be ll . Sparking at th e break ing contacts O f an electric bell is detriment al “ to r m v the platinum points , and many e edies ha e been devised to overcome it .

i ‘ " Sparking IS due to th e selfinductio n O f one turn O f the wire coil acting on its

as . - o r B ; this property is utilized in the g engine, L g S

h a lighting spark coil , w ere a f t spark is needed . to n ig ite gas . ELECTRI C BELLS A N D ALARM S

The differential bell has two windings in oppo

site directions . The action of o ne would be to produce an N - pole at one end and an S - pole at B the other . ut the second coil produces poles j ust

as O f the opposite , the polarity a magnet depends on the direction in which the curren t flows around it . Where the curre nt flows around the first wind ing the armature is attracted and its spring con tact meets the contact screw and allows the cur fl rent to divide , part owing through the first coil , the other flowing in the reverse direction in the

O pposite way . One coil would tend to produce a - e o S - Ole n N pole where the oth r coil pr duced an p , and these O pposite poles w ould so neutralize each other that there would be no magn etism . Th e armature would therefore be pulled back by its Spring when both coils were thrown into

s l circuit . In o doing it wou d cut out one coil and the same series o f Ope rations would reco m mence . As a spark is normally produced where mag * ne tism is lost O f a a by a break circuit , no sp rk p

a as roduce d pe rs , magnetism is p by a break of C in ircuit this case .

* - I of Fo r a full expl anation Of se lf induction se e N O . thi s se rie s.

1 4 ELECTRIC BELLS A N D ALARMS

A L S ’ U to , thence through and , to and back B to . Th e bell will continue to ring until the spring contact 5 is moved back and caught by the pro

e ctio n A j on the armature .

A continuous - ring attachment is also made and

n sold i most electrical supply stores , which is com ple te in itself and can be applied to any bell .

W ate r ro f B o e s . Fi p ll In g. 9 is an example O f a waterproof bell where the mechanism is almost

all entirely encased in a waterproof brass case . is The circuit made and broken inside the Case ,

" but the magnet cores proj ect th ro ugh ' it and act T i on a second armature placed outside . h s s e c ond armature carries the hammer which strikes the gong and is governed in speed by the contact breaking armature inside . BELLS A N D PU S H ES 1 5

f n Fo rms o Be ll G o gs . In orderto provide a f w variety o sounds , bells are provided ith gongs f O various shapes . ‘ i f F 1 0 O . g. shows the ordinary form gong

F 1 1 FI 1 2 FI 13 FI 1 I G . G. G. G. 0

Fi 1 1 Fi 1 2 . . co w g , a tea gong ; g , a gong ;and i 1 F . 3 g , a sleigh bell

A f l l‘ 18 Fi 1 4 O W e . coil steel also used , as in g , which on being struck by the hammer gives a pleasant but not loud tone .

F 1 4 I G.

B z z r Th e u e . The buzzer is the mechanism of

As a vibrating bell less the hammer and gong . the armature vibrates it makes a buzzing noise which does not carry as far as - the sound from a a struck gong . It is used chiefly for a desk c ll 1 6 ELECTRIC BELLS A N D ALARMS

and in telephone exchange work , or any place

n where general attention is not desired to the sig al .

e ratin B D i t nc O p g e ll s at a s a e . When it is desired to ri ng a bell situated at a considerable

O f distance from the push , the resistance the line

O becomes bj ectionable .

O f 50 N O 1 8 0 . C On lines feet, opper wire and upwards , the battery necessary would be very l a arge , two small batteries and a rel y would prove more satisfactory . i f In Fg. 1 5 the circuit of a simple form O relay

An u is given . adj stable contact screw C is placed where an extension 5 O fthe armature A can strike BELLS A N D PU S H ES 1 7

it . This extension i s provided with a platinum

Th as contact . e connections are in the figure . W hen the push P is depressed , the current from M e a E the main battery energizes the el ctrom gnet , A 5 and the armature being attracted , contacts

m T C and C eet . hese contacts lose the second cir " L cuit containing the bell ? and the local battery . The relay resembles a second push near the b ell , but controlled by current from a distance

O f advan instead being depressed by hand . Its tage consists in it needing but a very weak cur A rent to move the armature , which is held back by a light spring , or by gravity . The relay may then be se t near the bell and the wires from the push may be O f a very great B t . L leng h attery , which actually rings the bell , will thus only have to work through a few feet f O wire .

R du in i n B e c g Re s st a ce o f a e ll . Sometimes it is desire d to reduce the resistance the bell coils

O f fer to the current , the bell then working over a f very short line with few cells O battery . Or the bell coils may have been wound with fine wire for large battery voltage and a long line .

The bell coils may be put in multiple , the cur rent then dividing and one - half going through each spool . 1 8 ELECTRIC BELL S A N D ALARMS

U ntwist the j oint between the spools near the w yoke or iron bar to hich the spools are attached . Join one O fthese ends to the wire at the armature end O f the o th e r spool and the second untw isted end to the armature end wire O f its neighboring

s spool . U e short pieces O f insulated wire for these extra connections . The current now instead O f having to go through one spool and then the other , can branch through both at once . The resistance to the current O f one spool is

O f half the resistance two , the current through one spool w ill therefore be twice that through the

An d two spools as at first connected . as there are

- two paths for it , each one half the first resistance , the total will be only one—fourth the resistance f O the ordinary series arrangement . The same size battery will therefore send four

in' times . the current through the spools multiple than when they are in series . It is to be noted that the wire on one spool i s wound in the reverse direction to that on the other The reason w ill be apparent i f the two spools and yoke are considered as merely one spool bent in a U or horseshoe form . If both spools were wound in the same dire c tion they would be in opposite directions when the d U were straightened out , and woul cause like BELLS A N D PU S H ES 1 9

T poles at the same ends . hese poles would neu t raliz e w one another , so that there ould be no magnetic attraction . This can be readily proved by j oining together the tw o yoke ends and the two armature ends O f T the spool wires . hen pass the current through

two these j oined connections .

FI 1 7 FI G. 1 8 FI G. 1 9 1 6 G . FI G.

B tt o n Th e Pu Sh . h u Push buttons , or pus es ,

O f are made in a variety forms , with metal , wood , hard rubber , or porcelain bases . Fi 1 6 g. has a metal base , and is suitable for a front door .

1 is Fi . 7 g is a wooden pear push , and attached at the end of a cord which has the two conductors in braided in it , each , however , having its own i sulat o n .

Fi 1 8 a late g. is p push for an outside 2 0 EL ECTRIC BELLS A N D A L ARMS

Fi 1 9 O f g. is either metal , wood , or porcelain , and is the shape most commonly used .

A - three point push has three contact springs .

is O f One movable by means the button , one is

is below the movable spring , and the third above it . push button is not being depressed

F 2 I G. 0 the movable spring makes contact with the upper

But spring . when the button is depressed , these two springs part , and the movable spring makes contact with the lower one . This style O f push is used for special bell and

w . annunciator ork , as will be described later Th e form O fcombination floor and table push in Fi 2 0 g. is the most solidly constructed device of

Th s its kind . e lower part is e t in a hole bored in the flooring , the metal flange keeping it in

its place and preventing slipping through .

2 2 ELECTRIC B ELLS A N D ALARMS

B d be changed into an electric bell . eing screwe

is up near the door pull , a wire run from the lat L ter and fastened to lever . When the pull is drawn out the lever L turns on a pivot and a proj ection presses the insulated spring 5 against B the metal base . The circuit of the bell and battery being thus closed , the bell rings .

F 21 I G.

I n dicatin Pu h Butt n g s o . push button i s made which contains in the base a small electro

in An magnet series with the line . armature on a spring is fixed near the magnet poles . When the push is depressed , the current travels through

Ci this electromagnet , and as the rcuit is made d and broken at the distant bell , it is also interrupte in the electromagnet . The armature vibrates in unison with the bell and thus gives an audible indication that the bell is ringing . CH APTER III

Wirin Circuits and Tro u bles g,

Th W e ire . Th e size of the copper wire used 1 1 8 B 6 N O . N O . S in bell work is , or , and gauge , " r 2 2 e N O . 2 0 . and sometimes small , such as to

Bu 1 re t smaller wire than N O . 8 has too much sistan ce , and would necessitate a larger battery t power , even i f its mechanical streng h were not

Th e too low . insulating coverings are cotton satu

r ffin rated with pa a wax or compounds . Th e covered wires are variously know n as a n n un ciato r O f r , fice . or weathe proof wire , these terms being mostly for distinction O f the coverings and not for the use to which the wire would be put . Annunciator wire has two layers of cotton merely wrapped around the copper and then satu f rated with para fin . f O fice wire has the two cotton layers braided , the Insi de one being filled with a moisture - repel

ling compound . Both O ffice and annunciator wires have their outside coverings filled with paraffin and highly polished . From the ease with which fannun ciato r wire is 2 4 ELECTRIC BELLS A N D ALARM S

O f O f stripped its cotton covering , the braided fice T wire is to be preferred . hese coverings are made

O f. l rs in a variety co o . Weatherproof covered w ire is mostly used for w electric light ork , but the sizes given above are good for bell work , although their larger outside

diameter makes them harder to conceal . Th e approximate number O f feet to the pound O f O ffice and annunciator wire is given in the table .

fli ce W . O ire A n n un ci at or Wire .

Fe r F r e e t e . e t p e 1b . p lb

o i J nts . U pon the care with which a j oint is made much depends , a loose or poorly made joint will O ffer much resistance to the current .

Th e correct way to start a joint in annunciator , i 2 2 A f F . O . or fice , wire is shown in g bout three inches O f each wire to be joined is bared O f its insulation and scraped bright . The ends are then IRI N G C IRC IT A N D T U S 2 5 W , U S RO BLE

bent at right angles to each other , hooked together

as and one end firmly twisted around the other , i F 2 3 . An e shown in g. y proj cting pieces are cut

O ff solde re d , and the joints should then be to pre vent corrosion .

F I G. 23

FI 2 G. 4

Adhesive tape friction tape is wrapped Fi 2 4 around the j oint , g. , and pressed firmly to

O f gether so that there is no chance its unravelling . Th e tape wrapping Should extend across the joint and on to about a half inch O f the insulation h around eac wire . ‘ 2 6 ELE CTRI C BELLS AN D ALARMS

Ru nning th e W ire s . TO detail all the opera

O f tions installing a complex system of bell , alarm and annunciator w ires w ould be impossible from the reasons that conditions vary and space is lim ite d G w . eneral directions ill then only be given to enable the inexperienced to run such w ires as may be needed in ordinary domestic work and to guard against the most common causes O ffailure . Wires may be run in tin tubes to prevent the

O f t ma depredations rats and mice , or hey y be run with simply their o w n covering for protection ;it is presumed the latter is undertaken . In a case where the building is O f frame and in course O f e re ctio n th e task is much simplified.

H th e O f aving first decided upon plan , number bells , pushes , etc . and their location , proceed to run the wires first in order that the pushes , bells , etc . may not be injured .

But w here the house i s already occupied , as in the majority of cases likely to be met with by th e

th e . reader , bell and battery may be set first Take the case O fan ordinary door bell w ith th e push at the front door , the bell in the kitchen and the battery in the cellar . If possible get the wire on two spools ; it w ill simplify matters if both h w f ff S t e . ires are O di erent colors . tarting at push

f n and have a foot O each wire for co nection slack , and fasten each wire lightly to the woodwork with IRI N G CIRC IT A N D T U L W , U S RO B ES 2 7

- staples , or double p ointed tacks , never putting two wires u nder one staple nor driving in a staple SO S it cuts the insulation . ome cases will require a staple about every foot , on straight runs some times every three feet . In many Cases the wires can be partly con ce ale d in the angle between a moulding and the

O f wall , or even in a groove the moulding itself . W w hen running along a skirting , the ires may i O ften be pu sh e d out O f sight between it and the D floor . O not attempt to draw the wires too tight or the changes of the w eather may break the wires w hen the woodwork shrinks or swells .

The wires will be , one from the push to the bell , one from the push to the battery , and one

O from the bell to the battery . S it is probable that the second wire can be run right through a S mall hole bored in the flooring under the push , but inside the front door . In this case it will be perhaps easier i f the spool be left in the cellar and the end O fthe wire be pushed up from below and stapled to the woodwork near the push , leav ing the cellar work to the last . Only one wire will be run then direct to the bell upstairs and it can be better concealed than two . If necessary it may be drawn under a carpet

O and not stapled , or it can ften be forced into the B i run . f crack between two boards ut not , it 2 8 ELECTRI C BELLS A N D ALARMS

fo llo wm along the Skirting , g the walls until it

O reaches below the bell . It is ften better to go entirely around a room than to cross below a door . I f a door must be crossed the wire may either run up one Side O fthe frame and down the other

' O r laid beneath the carpet on the Sill . The former is preferable , but takes more wire . In many houses the bell wire as well as the bat te ry wire may be run across the cellar beams Fi ( g. in which case bore a second hole for it near the push ;do not draw it through the same

An d f to . O hole as the push battery wire , course , here work upwards with the Spool in the cellar .

H un aving reached the bell location , r the third

N o wire down into the cellar to the battery . w

SO O f connect up the push , baring an inch or each wire , push them through the holes provided in th e the push base , screw down push base and clamp the wires under the washers through which

D O r the connection screws run . this neatly , be su e

O f O ff the ends the wires do not stick out , cut what is left free O f the bared ends . Th en con ne ct the battery to the wire from the push and the

is wire from the bell . The last thing to scrape and fasten the bell wires to the bell binding posts . D O this SO that they cannot come loose and that t d hey make goo contact .

ELECTRI C BELLS A N D ALARMS

The bell should no w ring properly when the

push is pressed .

To sum w n up , one ire leads from one spri g

O f h the push to the bell , one wire from the ot er

O f to w spring the push the battery , and another ire from the remaining binding post on the bell to the im remaining binding post on the battery . It is material whether the zinc terminal or the carbon

terminal go to the bell or push .

i i n f n d Pu h C o mb nat o s O Be ll s a s e s . One of the wires in a bell Circuit may be replaced by Fi C the ground ( g. onnection may be made to a gas or water pipe or to a metal plate buried An deep in damp earth . y wire fastened to such a

FI 26 G. plate must be thoroughly soldered to it or a voltaic

se t w w th e action will be up , hich will eat it a ay at poi nt of contact . When one bell is to be rung from two or more points th e push e s are to be connected in I RI N G C IRC I T A N D TRO 31 W , U S UBLES

Fi 2 w multiple ( g. 7) as if they ere in series ;all would have to be closed to complete the circuit . If two bells are to be operated from one push

FI G. 27

i they may be in series (Fg. but in this case one O f them must be arranged for Single stroke .

28 FI G.

If both were vibrating bells the armature O f one would not y ib rate in unison w ith the other arma

F 29 I G. ture and the result would be irregular contact breaking and intermittent ringing . A preferable connection for two or more bells 3 2 ELE CTRI C BELLS A N D ALARMS

Fi . 2 9 and one push is g , where the bells are in T multiple . his requires more current than the series method .

FI G. 30

To ring two bells from either one O ftwo points

Fi 3 0 r the arrangement in g Will answer . It e quires only tw o wires o r one Wire and ground

AS return , but two batteries . both bells are in

FI 31 G.

multiple both will ring , the one nearest the push I being depressed ringing the loudest . This S a dis Fi 3 d . e 1 a vantage If the series arrangem nt in g, I RI N G C IRC IT A N D TRO 3 3 W , U S UBLES be Selected one bell must be arran ged for Single B w stroke . oth bells will ring with equal po er .

Fi 3 2 ir . C In g only the distant bell rings , the

FI G. 32

cuit having only one battery but three wires , or two Wires and ground return . A plan where tw o batteries are needed but only Fi 3 3 two wires , or one wire and ground is in g. .

Double contact or three - point pushes are necessary

FI 3 G. 3

here , making one contact when depressed and a second one when not being touched .

In this figure only the distant bell rings . 34 ELE CTRI C BELLS A N D ALARMS

Fau lt s in Be ll s . On examining many electric bells it w ill be noted that only one bi n ding post is i n sulated from the frame when the latter is

O firo n Fi As . 5 . ( g the armature spring in electrical connection with the frame F by reason

O f C its metal screws and support , the ircuit may U run from the insulated post to the magnet coils , thence through the insulated contact screw C through the armature spring (wh en it is making contact ) and through th e frame to the uninsulated post I

This saves labor , wire and complication , but if th e O f U w W V insulation the post , the ires , or the C contact screw be injured , the current may take a short path back to the frame .

I f C w ere thus grounded , the bell would act as

- a Single stroke bell .

If U were grounded , the bell would not ring IRI N G C IRC IT A N D TRO 3 5 W , U S UBLES

w at all , as that ould be a short circuit on the bat te ry between I and U and the latter would also result if the bare wire were touching the frame V at . If the bare w ire touched the frame beyond M M

is W w - that , along , it ould be a Single stroke bell , as i f C were grounded ; AS any one of these faults is likely to occur they should be looked for when the bell acts im

O r . perfectly , not at all A very common fault in a bell is when its arma ture sticks to the cores and thus does not make contact w ith the contact Screw . This may be from. a weak spring or because O f the loss O f the pieces of brass inserted in the ends O f the cores to keep A the armature away from actual contact . piece O f a postage stamp stuck over the core end will

O ften help out in the latter case . A high SCre e ch ing noise from the armature vi b ratin g too rapidly but with too little play , may be from excessive battery power or the contact Th screw being too far forward . e former will generally be detected by the violent sparki ng as well as the rapid vibration . In very cheap bells the platinum contacts may be replaced by German Silver or some other metal . Platinum is necessary because the Sparking would soon corrode other metals , but it is very ELE CTRI C BELLS A N D ALARMS

TO expensive . test for platinum put a tiny drop

O f nitric acid on the suspected metal . If bubbles A or smoke appear it is not platinum . fter apply w ing this test in any case however , carefully ash

O ff and remove all traces of the acid , as it Will cor rode the metal into which the platinum is riveted . Dirty contacts will decrease the current in the bell coils and it will not work well , if at all . L oose contact screws and Wires also give

Th e O f O f trouble . adj usting the contact screw is

at the utmost importance , and should never be i tempted unless t is clearly necessary .

Fau ts in L ine l . In looking for a fault in a bell circuit make sure the battery is work ing ;if

O tw o w nly one or cells , put the ends of two ires attached to the terminals on the tongue "a metallic taste Will indicate current .

‘ Then see that the Circuit wires are firmly clamped in the terminals and no dirt or corrosion on the connections . Next examine the push button and see that the wire connections at the Springs are perfect . If there is no movement O f the bell at all when the push is pressed in , take a pocket knife or screw driver , and touch the blade across the push

Springs . If there is current flowing sparks will be seen when the blade breaks contact between

ELECTRI C BELLS A N D ALARM S current will travel from the battery to the cross S at , then back along the second circuit wire to the tongue and through the Short wire to the battery .

35 FI G.

If no current is Obtained in this way it is prob able that the Wire is broken .

36 FI G.

The easiest w ay to find t his is to take a bell to the battery and connect it between the circuit i wires and the battery (Fg. Then with a Sharp knife carefully cut away a IRI N G CIRC I T A N D TRO 3 9 W , U S UBLES little piece O fthe insulation from each wire beyond the bell and battery and short circuit the b at e d K K spots with the knife blade . eep working towards the push . The bell will ring each time

at K K until the break D is passed at C it will n o t. It becomes an easy matter then to locate

I t . r i F . 3 7 I f the bell and push are far apa t , as in g , a break between the push and the bell may be ff found as show n . With the knife blade K at di er ent points the bell will ring , but after passing the break D it will not ring . Such Simple tests as are here given can be car ried out by any one , but far better results will be

Obtained if the reason for each is first learned . This can be readily done by a careful study O f the diagrams and text . CH APTER I V

Alarms

Fire A arms . ar l Thermostats , heat al m s and ar fire al ms are all practically the same , the term thermostat being applied principally to the appa

C ratus which closes the electrical ircuit .

F 8 I G. 3

Thermostats act on the principle that heat causes

O f l e . expansion whether substanc s , iquids , or gases Th e degree in which different substances ex pand varies for the same increase in temperature . This fact i s used in a common form O f thermo i Fi 3 8 . A stat shown n g. strip of wood or hard rubber B has a strip of thin sheet metal 5 riveted

. i i d e nd to it Th s compound strip s hel at one , by ALARM S 4 1

" a lug L screwed fast to a baseboard . U pon an increase O f temperature the hard rubber expands more than the metal strip and the compound strip “ A bends towards the adj ustable contact screw .

to uch l n U pon g the latter , the circuit through the B C 5 bell , battery and the metal strip is com A le te d . p , and the bell rings contact screw can

O f S R be arranged at the other Side , which will

O f give warning a decrease in temperature, as the rubber contracts more than th e metal strip " I n some thermostats of this character two metals ff f o having di erent coe ficients of expansi n , such as

O f steel and brass , are used instead metal and hard rubber . Thermostats O f this nature are much used in w incubators , and they can readily be combined ith

‘ e e lo se h o t - l ctric apparatus to open or c air valves , 4 2 ELEC TRI C BELLS A N D ALARMS

dampers , etc . , and thus regulate the supply O f hot air , hot water , or gas . A thermostat much used in fire alarm w ork has

is air An in a thin metal chamber which tight .

O f crease temperature causes the air to expand , which swells out the walls O f the chamber and closes an electric circuit .

FI 4 G. 0

Fi 3 The mercurial thermostat shown in g. 9 has n a glass tube T and bulb containing mercury . I to U each end is sealed a p latinum wire P P . pon the temperature rising to a predetermined degree , the expanded mercury completes the circuit b e tween P P and the battery C and bell B are put in operation .

Fi 4 O g. 0 is the pe n circuit system most used by ALARM S 4 3

O f six the fire alarm companies , only one circuit thermostats being illustrated . It will be seen that if any thermostat closes th e circuit betw een the outer an d inner W i res O f the A B ring , current will flow through the corre spo n ding drop of the annunciator and w ill attract

A O f e the armature the r lay . This will cause the

AS an bell to ring . the relay is c onnected to the nunciato r th e as before Shown for annunciator bell , it O ffers a common path for any drop to the bat te r T r c y. hus the bell will ing for any cir uit , but the individual drop only will fall . In a Simpler circuit the relay may be dispensed with and a vibrating bell only used . Thermostats may be operated on open or closed circuits , that is , they may give the alarm by clos ing a circuit and ringing a bell , or by opening one and releasing a contact spring as in the burglar alarm syste ni to be described later .

W ate r L e ve l Al arms; Where it is desired to Sign al the rising or falling O f water in a tank

in above or below a given point , a water level dicat r Fi 4 1 o as in g. may be used . A hollow ball H is mounted on the end O f a rod which slides vertically in guides , not Shown . Adjustable stops S 5 press against a Spring R arm , pressing it up or down , according as the 4 4 ELECTRI C BELLS A N D ALARMS

R Or . water level is rising falling If rising , makes w A contact with the adj ustable scre , if falling ,

D Cir with , in both cases completing the electrical

' i B cu t O f the battery C and bell .

F 41 I G.

A i Fi 4 2 nother and Simpler form s shown in g. , where the ball H is mounted on the end O f a

L c lever pivoted at P , its rise or fall ompleting B C the circuit of and as before .

4 6 ELECTRI C BELLS A N D ALARM S

O f In both forms indicator , a means must be provided that an undue rise may not bend the T lever . his may be accomplished by using contact

O f w Springs instead contact screws ;it is , ho ever , then harder to adj ust the indicator to fine differ

n s f e ce O level . I n all cases the contacts must be faced with n plati um to prevent corrosion .

Burgl ar Alarms. A burglar alarm is a device

O f for indicating the opening a door or window , by the ringing of a bell or operation O fan annunci ator . The contact apparatus at the points to be protected may either open an electrical circuit or

m o difica close one , in the latter case being mere

O f tions push buttons . The Simplest form is the

- latter or open circuit method . The Spring contact to be inserted in the door j amb or window frame is SO constructed that while under pressure the contacts are kept apart

Bu and the circuit is open . t when the door or

window is opened , the pressure is released and

a spring forces the contacts together .

Fi 4 - g. 4 is an open circuit window spring fitted in the window frame SO that when the window

is closed the spring lug S is pressed inwards , “ B breaking Contact with the base . th e If the window is raised , the lug flies to ALARMS 47

position Shown by the dotted lines , and making B contact with , completes the circuit through bell and battery . These springs are fitted in the Side

of the window frame in a vertical position and are entirely concealed w hen the window is shut .

In the closed - circuit system the reverse hap Th s pens . e pres ure O f the closed door or win

FI 45 G. dow keeps the contacts together an d its opening enables them to spring apart;

Fi 4 5 f - In g. is a diagram O a closed circuit C R burglar alarm , a cell of gravity battery , a 4 8 ELE CTRI C BELLS A N D ALARMS

F relay , the fixed contact and M the movable con O f n 5 tact the Spri g , a stud proj ecting through the base O fthe spring and pushed in by the closed door . W 5 hen the door is closed , being pushed in ,

F 4 I G. 6

O f C R F Th e M . the circuit , , and is closed magnets O f the relay hold the armature arm A

But w forward against a hard rubber contact . hen S R is released , the relay circuit is opened , loses A its power and flies back , making contact . and L throwing in circuit bell B and battery . ALARM S 4 9

A form O fbell and relay combined is shown in i 4 6 H A Fg. . ere the armature is held against the magnets while the circuit through the spring F

is Bu and batteryG closed . t on Opening this cir cuit the armature flies back and makes contact with an adj ustable contact screw 5 puttin g in

C is racti circuit a local battery . The bell now p

FI 4 G. 7 cally a vibrating bell ;On a closed circuit it rings until the circuit is again closed or the battery runs down . A di fferent connection O f the same scheme is Fi 4 T . 7 . g , where only one battery is used his must be a gravity battery or some other closed circuit battery . The circuit can be easily traced in the figure and needs no special description . 50 ELE CTRI C BELLS A N D ALARMS

Both O f the latter schemes are inferior to one using a separate relay . If the circuit at the spring were quickly closed again the bell would either S stop ringing , or be O hampered as to ring very weakly .

FI 48 G.

Fi 4 8 A relay made as in g. has no spring sup A port to the armature , which falls down by grav

. C ity The adj ustable contact is screwed far back , SO that the armature must fall a considerable dis tance away from the electromagnets before it

makes contact . This ensures that the armature will not be attracted and the bell stopped from

ringing by a t e - closing O f the c1rcu1t at the door

r o window spring. i is A Shade spring (Fg. made for either ALARM S 51

open or closed circuits . In operation , the Shade is pulled down and its string or ring hooked on T H to H . his draws up a trifle against a spiral spring and its lower end makes contact with an insulated Spring 5 closing the circuit . If the

is Shade disturbed , the spiral spring on the lower part O f H is released . and it causes a break O f n contact with S in the directio of the arrow .

5 so When made for open circuit , is bent that

FI 49 G .

is re while under tension no contact made , but

f n lease O te sion causes the contact .

Fi 50 O f tw o g. gives the wiring windows and

- a door on the closed circuit system . It will be seen that the contact springs are all in series , opening a window or the door will thus break the circuit . When setting the alarm at night by connecting up the batteries , relay and bell , Should any one O f these springs be open the relay armature will not hold , and the bell rings .

54 ELECTRI C BELLS A N D ALARM S

o A m M isce llan e u s l ar s. Th e Applegate elec trical matting IS composed of w ooden slats with Springs so arran ged that the weight O fany person stepping on it w ill close a circuit and ring a bell . It is intended to be put under the ordinary door mat or under stair and room carpeting . The Yale lock sw itch is a Yale lock and switch U combined . pon any key but the right one being

i i inserted , a c rcu t is closed and an alarm bell is rung . CH APTER V

Annunciators

Th e Annunciat o r. Th e mechanism O fan an

‘ n unciato r consists O f electromagn ets w h ich allo w Shutters to drop or needles to move on the cir cuits being Closed . A bell is also rung in most cases to call attention to the annunciator . The

O f number the circuit is marked on the Shutter ,

or near the needle, either shutter or needle being replaced by a reset device, w hich may be mechan ical or electrical . Annunciator drops are made in a variety of Fi 5 forms . g. 2 illustrates the principle under

O f lying nearly all them . When current flows th ro ugh ' th e magnet coils

M A is , the armature attracted , and being pivoted at H P, the lever hook rises and allows the 56 ELE CTRI C BELLS A N D ALARM S weighted shutter S to fall and display a number painted on its inside surface . ' i 53 The needle drop in Fg. is one that has met with great favor and works as follows "the soft iron core O f the magnet C has a hole drilled

An 5 . th rough it , in which turns the shaft arrow or needle is attached at the front end over the

F I G. 53 F I G . 54

A B face of the annunciator . notched arm is fixed on the rear end O f the shaft and is held in A a horiz ontal position by the end of armature . W C A hen the current flows around , armature C turns on its pivot towards the core of , as in Fi 54 . B g , unlocking , which falls and thereby 5 partly rotates shaft and the arrow . W hen it is desired to reset the arrow and arm , A N N U N CIAT ORS 57

is r a button pressed upwards , which aises a rod R carrying an arm . This latter arm in turn B raises to its former position , the heavy end

O fA l B falls , and its pointed end ocks .

ah Pendulum , or swinging, Signals are used in nunciato r is t work , where there a liability tha the

FI 55 G .

ordinary drop shutter would not be reset . They ,

n se c however, only give a visible sig al for a few ouds , and are therefore liable to be overlooked . Fi 55 In g. a pivoted arm carrying a soft iron armature A and a thin plate B - having a number on it is free to swing in front O f an electro mag

ne t M . ELECTRI C BELLS A N D ALARMS

When the Current flows in the electromagnet

‘ c and the armature is attra ted , upon the circuit being broken at the push , the armature is released and the arm swings to and fro . The drops O f an annunciator are wired up as Fi 5 6 . in g. One end O f each coil is attached to a common

F I G. 56

C . return wire , the other end goingto the push P

W s t h e O f is hen P is depres ed , circuit any drop

M C r u through along th o gh bell , battery and up common battery wire W back to other contact

Of D n push P . epressi g any push does not there

’ fore affect any other drop but th e one controlled b yit . A N N U N C IATO RS 59

W i in u an Ann n iat o r g p u c r . A diagram of the connections for an annunciator with a separate Fi 5 bell i s given in g. 7 . Where the bell is con taine d in the case a terminal will be generally found for connection . Th e figure Shows a wire running from the bat te r O f T y to one side each push button . his is the common return , or battery wire, and saves instal

FI G. 57

ling two wires from each push ; It Should be w larger , ho ever , than the rest of the wires , gener 1 6 B N O . . S ally about . All the w ires for an annunciator Should be run T f before connecting up . here are di ferent methods

O f n w sorti g out the ires at the annunciator . One w ay is to connect the wires (except O f course common or battery return wires ) to the drops in any order . Then an assistant travels from push to push and presses each button , noting the 60 ELE C TRI C BELLS A N D ALARM S room numbers and the order in which they were visited .

A S its each drop falls , number and order is noted . Comparing this with the list made by the assis tant will Show the correct changes to make .

FI G. 58

Fo r S 1 2 3 4 5 6 instance , uppose pushes , , , and 3 4 5 1 were pressed in that order , and drops , , , , 6 T 2 and fell in that order . hen the wires at the annunciator would be changed as follows

6 a would alre dy be in its right place .

Anoth e r w ay is to commence by c twisting to

62 ELECTRI C BELLS A N D ALARMS

FI G. 59 A N N U N CIATORS 63

each room the top contact and push spring ct are normally together . one O f the pushes below the annunciator is ed F is n , battery throw in series with the

the room . t when the room push is pressed its bell is ut and the circuit ; becomes like an ordinary

ia o r c t circuit . CH APTER V I

Annunciato rs and Alarms

T e Re u r Ca l S s e m A hr e e Wir t n l y t . three

‘ w ire return call a n n u n ciator system 18 Show n in Fi 60 . g. T w here are two battery ires installed , from w hich taps are take n O ff and le d to each room or push button . Three w ay or return call push buttons are n used as Show n at poi ts marked B. th e A In diagram , the bells are marked , the

in n n D n n drops the a nu ciator , the an u ciator bell C an d the return call buttons in the annun ciator E Th F Th . e e batteries are as shown at . heavy black outli n e encloses the annunciator mechan ism and connections which are drawn diagrammatically f n for the sake O clear ess . T n w hree stations o ly are Sho n on the Sketch , but the annunciators which are manufactured by E w s an d I n f N w Y CO . c . O e d ard , , ork , are made in all standard Sizes .

I n a i E A nun ia s Th e al st ll ng l e vat o r n c to r . inst l ing O f e lectric bells an d ann unciato rs in el e vators n o t n an o m o does prese t y special pr ble s , alth ugh the apparatus use d must be selected with a view to

64

6 6 A N N U N CI ATORS AN D AL ARM S its bei ng suitable to withstand the sho cks i ncident t se c o elevato r rvi e . I n general th e wires leading from the push but to n s o n the different floors to the bell o r an nunciato r in an d m the elevator , are flexible ade up n O ne e nd to i to a cable . of this cable is attached

O f t o car e nd the underside the eleva r , the other n o w o n bei g fixed usually to the elevat r all , at a p i t f midway between the top an d botto m O the shaft . I F 6 1 d m O f n n ig. is Shown a iagra the ge eral O f o ff in circuit used, details c urse di ering each

n n i stallatio . O ne po int to b e taken care O f in elevato r work m n Th e n is the attach e t of the cables . conti ual movement tends to break the wires at th e two ends if goo d flexible cable is n o t used an d the installa n in w m n nn tion do e a ork a like ma er . Elevator cable is a standard article and may be n pro cure d through a y electrical supply sto re . That most co mmo nly used consists O f th e requisite number O f copper co nductors each composed o f

' 1 n B n 30 . a S . n u 6 stra ds N O . d gauge soft a d n n n T n ti ed copper wire . hese flexible co ducto rs are in sulated with two reverse wrappi ngs O f cotton an d n n Th n c s o e braid of c o tto . e i sulated o nductor are cabled together with a steel suppo rting strand w ns n th e here extra te ile stre gth is required , as in

Th n m c n case of extra long cables . e u ber of o 2 ducto rs generally ranges from 3 to 0 inclusive . Th e wires leading fro m the push butto ns to the cable should be preferably rubb er covered an d

68 AN N U N CI ATORS AN D AL ARM S

i O w o o m o de bra ded . nly here ec n y at the utset is sired m ay ordinary annunciato r or Offi ce wires b e

empl oyed . A connection bl o ck carrying binding po sts is used at eac h point where the cable co nnect s to th e r nn n T m a push butto n wires o to the a u ciator . his y

- m m o r m . be ho e ade purchased ready ade, as desired

B lar A An u ia o A m urg l arm n nc t rs . lthough al ost any annunciato r m ay b e used fo r O pen circuit m w n n burglar alar ork , they usually do not co tai certain devices wh ich are desirable in burglar alarm w ork . I n Fi 62 S w f g. is ho n a diagram O a burglar alarm w b n m O f b annunciator, the vie ei g sche atic the ack r boa d . Th e references are as follows " A is the main alarm bell situated Wherever desired an d co nnected n BB Th e to the bindi g posts . battery connection leading directly t o th e b attery K is marked C an d that leading to the contact spring is marked

D Th - Off sw c E c Off b w . e cut it h uts the attery hile n n G F is the co nsta t ri g switch . is the upper bar H w b ar w J" no and the lo er , hile the letters de te n n Th e w w n the i dicati g drops . do or and indo spri gs 5 At L w c w are lettered . is a s it h hich may be used to disconnect the entire burglar alarm sys W s n tem . here it is de ired to disco nect only a sec n m w e on n tio at a ti e , the s itch corr sp di g to the section is turned Off the upper bar G and o n to the

l o wer bar H .

70 AN N U N CI ATORS AN D AL ARM S

Cl k A a m i A o c l r Circu t . diagram O fthe W i ri n g and co nn ectio ns o n th e back board O f all clo ck m is Fi T m . 3 d alar s illustrated in g 6 . his iagra e mb o s nc O f c die the pri iples the last described ircuit , n clo ck ~o e rat d but i cludes the circuit of a p e alarm .

Be s fo r H V a s Th f ll igh o lt ge . e use O electric

s o n n c s is m n bell lighti g ircuit beco ing quite ge eral , as s n s O f n and it obviate the eces ity usi g batteries, thereby Simplifies both installation and maintenance . There is no fundamental Objection to o perati ng m b n Pro ake and reak bells o electric light circuits .

d n o and m m vi i g the v ltage a perage are the sa e , there is little difference between the current from

- n n m a direct current dy amo a d that fro a battery . But owing to the higher voltages o f the lighti ng cir cuit over that generally employed from batteries th e bell co ils must be wound to high resistances to wn n n T so keep do the curre t stre gth . here are al other slight changes to assist in suppressi ng spark in n n o . g, as have bee already treated

W c is n o t 220 here the ircuit over volts , the bells are wound with fin e w ire an d have also self - co n i F r 5 n a ta ne d c . o 00 s a d resistance oils volt over , resistance lamp is conn ected in with the bell which

n l SO- in this case is wo u d for a vo lt circuit .

These bells up to 6 - in ch an d inc lusive will operate n n e n o n circuits of either dire ct or alter ati g curr t . Above this Size it is n eces sary to u se specially constructed bells on alternati ng current circuits . M o st large ho tels and Office buildi ngs having

2 AN N CI A ORS AN D AL ARM S 7 _ _ NU T direc t current lighting service are usi ng it for ring ing bells and similar w o rk to the total exclusion o f batteries . Where the number O f un its to be operated justi it m o s in o nn n fies , otor generat r are operated c ectio with the lighting mai ns to pro duce a lo w vo ltage h Th nn most suitable fo r t e bells . e co ectio n s in th is case are no different to those when batteries are employed .

B - Tr o e rs Th e e ll ringi n g ansf rm . best system for operating b e lls and annunciato rs fro m alte rnat ing current circuits is undoubtedly that employi ng small specially co n structed transformers to reduce

T n m s n e the voltage . hese tra sfor er are bei g us d universally fo r hotel an d Offic e wo rk where alternat i T m in . S n g current is ava lable hey are i ple, bei g merely o ne or more coils of well in sulated Wire wo und on soft iron cores an d h avi ng co nne ction s n an for bo th the lighti g circuit d the bell circuit . As a general rule the co ils a re divided as to their number o f turns or according to the ratio O f tran s m F r m I f . o c for ation desired exa ple , the ircuit were 110 vo lts and 10 Volts was require d for the l th e m O f n in n be l circuit, total nu ber tur s the tra s

m w n n c ir for er ould be co nected , to the lighti g cu it and to the bell circuit . Th e bell - ringing transfo rmers on the market are

O ne m e Fi m d . 64 a e in several styles s all styl , g. , fo r n 110 an d si gle residences , is for use on volts p ro duces a bell voltage or secondary vo ltage as it AN N UN CI ATORS AN D AL ARMS 73

FI G . 64

FI G. 65

BELL -RINGIN G RAN FO RMERS T S . 74 AN N UN CI ATORS AN D AL ARMS

6 A Fi 5 s o . 6 is termed , of v lts nother size , g. , of thi o h as 6 12 transf rmer three secondary voltages , and 18 c O f w , ea h hich can be used by connecting to the n n o right bi di g p sts . I t is to be noted that where the lighting service o m m o v ltage or pri ary voltage varies fro the ab ve , the secondary voltage delivered to the bell circuit w in I ill vary like propo rtio n . t should also be not ed

Of n c that a careless reversing the co ne tions, that is conn e cting the secondary leads to the light s O f m wo ing circuits, in tead the pri ary leads uld cause a like high vo ltage at the other terminals of r o n in the transfo mer, raising it in due proporti f T stead O lowering it . hus such carelessness wo uld pr o duce a voltage of volts instead O f 6 if a transformer i ntended to deliver 6 volts from a 120 n volt circuit was w ro ngly co nected . l m Th e resu ts ight very w ell then be dangero us . All t m w ransfor ers are properly marked , ho ever, and such an error only occurs through ignorance o r carelessness . Th e i nstallati o n O fthese b ell - ringing transformers

‘ ’ is simplicity itsel f; they re qui re nO care after in stallatio n an d h ave met With the approval O f the

“ r National Bo ard O f Fire Underwrite s .

Co mb inatio n Circuit s. Circuits intended pri marily fo r ele ctric b ells or annunciato rs in h o uses and apartments may O ften be also made to serve o o o for other electrical devices such as d r peners , T id o . h use telephones , etc his subs iary apparatus

76 AN N U N CI ATO RS AN D AL ARM S may be i nstalled with a little additi o nal wiring or

r s w no t n an w s w n pe hap ill eed y other ire , as he bo c r n n th the devi es a e o t used at o ce . Electrical do or openers are great conveniences and are practically i ndispe nsable where th e outside doo r is on ano ther level to the lo cation O f the dweller or where two or more fam ilies occupy the

m Th is m n n f . e c c O sa e house devi e si ple, o sisti g an el e ctrically release d spri ng- plate against which the l i n o m h an d n n lock bo t s r ally eld a doo r openi g spri g . W n o n n e he the d or ope er butto is pr ssed , the n n " lOck b o bv spri g plate is released , releasi g the lt Th e n n the same action . door spri g the forces the doo o c n w r pen enough to lear the ope er plate, hich o n n flies back int positio whe the button is released . T'hese door Openers are made in several fo rms d m o n n o i n for oor fra es , such as those thi do rs , ro

s rim t c o s gates, for urface or locks , for hi k do r ,

n d “ 1 slidi g o ors and any other regular type 0 doo r .

' Th e push button is the same as used for electric e n d w e Th e b lls a may be located h rever desired . F 66 pushes are wired in multiple as shown in igs . and 67 w c two t O f -O f , hi h are circui s a type the

W E n s m O f e estern lectric i terphone, a yste hous telephones supplied for houses and b uildings of Fi w c w every Size . g. 66 sho s a cir uit hich provides

s w b and telephone ervice bet een the vesti ule , the t th e n w n n c apartmen s , door ope er iri g bei g learly I n Fi 67 c ui indicated . g. the irc t provides a more n th e n o extensive service, enabli g ja it r, the apart ments and the tradesmen to inte rco -mmun icate in

78 AN N U N CI ATORS AN D AL ARM S

m Th e o n n the most desirable syste . do r ope er Wiri g is r w n also clea ly Sho . Th e c onven ience O f having telephone c o nnection in the house o r hotel and its advantage s over speak ing tubes are t o o well known to need extended

m W e c b n co ment . here el ctri ells have already bee installed it is quite feasible no w to use the same wires for telephones also . Telephon e sets especially designed for this serv ice are manufactured by the Western Electric Co m

n “ in n T m pa y their interpho e series . hey are si ple and o m an d m a n e wh o c pact , y be i stall d by anyone u can p t up an electric bell .

F A a m r s A m ire l r Ci cuit . fire alar circuit suit

fo r n o O f able factories , private pla ts or gr ups

n in Fi i m n 68 . s w . s buildi gs is ho g It a series syste , w C o c o n o n n w n ith l sed ircuit , the g gs s u di g he ever the circuit is opened wheth e r by th e contact breaker in h e c n n f w the boxes or by t a cide tal breaki g O a ire .

T em n s in od w o n his insures that it r ai go rki g order , as w n an o f c is n w he y p art the ircuit ope ed , a arn a n o n ing t p is sou ded n every bell or go g . Th e boxes have co ntact breakers which send a m o f m an separate nu ber i pulses for each box , thus n un in x n m n Th b o o c gthe bo u ber o each gong . e xes an d n m a o n wh go gs y be l cated a y ere, as the system rf l is pe e ct vflexible . Th e reference letters in the diagram are as fol lows " C indicates the go ngs which are p referably

- m n co s n of the electro echa ical type, a iled p ri g pro

80 AN N U N CI ATORS AN D AL ARM S vidin o w c b g f rce for the blo , electri ity eing merely n mm used to release and retai the ha er or strike r . Th e alarm bo xes are m ark e d BB an d the b attery w is th e c D hich of closed ircuit type is marke d .

I e rior F re A ar S st e A nt i l m y m . nother syst em su itable more particularly for indoo r operati o n is in Fi H 69 . e m i n illustrated g. re the alar s give b y breaki ng the glass front O f an alarm box and re n o r s n an c c n leasi g pre si g ele tri al c o tact . Th e box sounded indi cates by causing a drop to fall o n an annunciator an d at the same time rings m Th r an alar bell . e latter a e gen erally provided w n n n c m nt w c ith co sta t ri g atta h e s , hi h keep the n n i h ff bell sou di g unt l S ut O . Th e annun ciator S ho w n in the diagram has

w o n o n c n c s itches for c tr lli g ea h i dividual bell ircuit , and f r c o o O f n m also o ntr l the e tire syste . There is n o practical limit to the number O f sta

t m n m n S tions in his syste , it bei g deter i ed by the ize b of the annunciator used or y other obvious facto rs . Th e referenc e lette rs o n th e diagram are as fol w " A a b e w ma w e lo s , al rm lls hich y be located h re

B - bo o s . ever de ired , break glass alarm xes als lo C nn n d cate d n o . o at convenie t p ints , a u ciator r ps , D s w o n nn n c o w nt in , itches a u iat r hich co rol each c n n an to dividual bell ircuit, e abli g y circuit be cut

cut i o out, in or tested W thout disturbing any ther

r E n m w c s n all ci cuit . is a ge eral alar s itch, au i g n bells t o ring at o nce whe it is o perated . Th e battery F varies w ith the number O fbells and FI RE A L ARM SYSTEM S 8 1

o m u bo xes and the length of line , fr three cells p

A —o ut w H to o ut wards . cut s itch is added cut the ent ire system by open ing the battery wire .

FI G 69 .

Th e n n is at I b a nu ciator bell , an auxiliary ell being

n added in multiple with it wh e necessary .

FI RE AL ARM SYSTEMS

Ala m S e m f r Co side a A a Fi re r yst o n r bl e re s. Where the area is m o re exten sive an d the number

n n b th e m i s in of statio s co sidera le, syste llu trated I t Fi 70 . g. is very suitable consists of the requisite

m r - s s and m nu ber of b eak gla s boxes, bell a ore I n n elabo rate annunciato r system . ge eral detail s it m m rese bles the last syste , but uses a relay to send out th e current for ringing the alarm bells .

W n s m u n he a box operate , the current i p lses se t o n the lin e act o n the relay i nstead of directly on E the bells . ach stroke of the relay closes a local i n an d th c rcuit which i cludes the bells e battery .

This sy stem does away . with large batteries and is very e n'co n o mical o f wire Th e current n eeded e m w in for the r lay is very s all , hereas a direct sys te m o f an d n any size , the current voltage to ri g a numbe r of bells located at wide i ntervals would be prohibitive . Th e reference letters are as follows " AA are

m BB - s the alar bells , the break glass alarm boxe , ' C th e nn n o D is th e w re is a u ciat r bell , relay hich mai n s clo se d when an alarm comes in keeping th e

c n n n n n ff E r bells o sta tly ri gi g u til shut o . is a e sis ance o n F t c il a d is the battery . A system cu t- out s witch G an d I f switches o n the an nunciator for controlling i ndividual circuits

d H H nn nc o o s are also provi ed . are the a u iat r dr p and K is a co nstant- ring sw itch whi ch can al so be

“ u sed for a general alarm to ring all the bells at o nce .

’ D u b e ll Fam o u s F rm u l e s o as . KN O WN As

N on Plus Ultra. Soda. Fount ain Re q uisit e s of M ode rn Time s.

. n B U R By G . E L L E .

A ractical Recez t Boo/e a; fi ru i sts Ck emi ts on ectio n e rs a n d p lfi f gg , s , C f V e n de m o Soda W t r f a e .

S l N O PS l S O F C O N TE N TS . — I NTRO DUCTIO N N ote s o n n atural fru it j u i ce s an d i mprove d m e th o ds fo r th e e t n e n t h e f u t Wash i n a a Se c t . and ir p r p r io . l i g r i g ss n th e f e u t . e atin th e u ce N atu a f u it s u s an d pr i g r i Tr g j i . r l r yr p m d f e o e a ati n . m u s o pr p r o Si p l e or stock syr p .

FORM UL AS . FR R —B ac r r I T SY . k be ack c u e nt ack as e r ca U UPS l r y, bl rr , bl p b r y, ta Wb a ch e c nc d a e cran e i me e ac h ine a e , rry, o or gr p , b rry , l , p , p p pl , u m u ince as e e d u e n r ran e u e rn n . r c t e d sc a e pl q , r p b rry, rr , o g , pp o g gr p . st aw e r W d a e N EW I M PRO V ED A RTI PI CI AL FRU I T S Y R r b ry . il gr p . UPS A e a i c t an ana itte an e ack e ack cu re n t p p l , p r o , b , b r or g , bl b rry, bl r , ch e r ci tr n cu ac a a e se i e e m n ime m andari n m u l. r y , o , r o , gr p , gro ll , l o , l . e ne cta n e e ach e a i ne a e u m u in ce as e r b rry, ri , p , p r , p p p l , pl , q , r p b r y , re d u r n n n F c e t st aw e swe e t ran e l ar e ri e a i a . Y r , r b rry, o g , g , v ll ANC

S O FO U N T AI N R Ps -A m r si a i i e ca- Rin a ca an S Y U . a c a c c v DA b o , p ll r , o , o i a co caw m o e xce s m e a k a c ca k a- k i na k a- ani a ll , , l ior , i p ri l , ol o , ol , ol v ll . ‘ k a - vm o n e ct a n o e an e at Sh e rb e s ru o f se s s u o f ol , r , y , org , , y p ro . yr p le ts AR F L FR E E —A e a r c t an an a e r vio . TI ICIA UIT SS NCES . p p l , p i o , b , b g ' am t ack ack ch e a k c u ant u e e r c i t n . e c o bl b rry, bl rry, bl rr , bl b r y , ro , c an e r se e a e e m n me fru i t m e n n e c tari ne r b r y, goo b rry , gr p . l o , li , lo , , an e e ach e a in e a e u m u i nce as e re d c u ran t or g , p , p r , p p p l , p l , q , r pb rry , r , st a e r CO R FR P A Cl d s u ti n o f O . r wb ry . NCENT ATED UIT H SPHATES ol o — ff r n f m u s h o s h ate st aw e t an e n e w d ch e r 2 di e e t a . p , r b rry, g ri , il ry 9 or l pl EW M L T P O — 6 FO R G AN D O M W PH o s A H SPHATES 3 . EI N D ESTIC INE — PH ATE - C R - A T RT 8 S OL BL E FL V O R G E x S E M FR L C A S 2 . 9 . A UIT U A IN — — P 8 ' M L K R AN D N EW M O R I . T ACTS E SSENCES I 4 . DE N UNCHES I

- — - P N CH P I M N E W FRU . T U Es I FR T E 2 FR E 1 8 . 7. UI UNCH S 3 . U T ADS M — N EW E G G P O — l FR S R C G I . E HA PA NES 7 H SPHAT S 4 . UIT JUICE HA ES

- 2 E G G P O E S H R H O T E c o P O S R . 4 H SPHAT A ES . H SPHATE HA ES W E BI R S R — 1 2 S o L U BL E W E B R EXTRAL TS— I Z IN TTE HA ES . IN ITTE S — — N E I L L M O E I I E CR M S O N O N . PO I SO N W TA A E A 8 . EA A 3g I N N D S ’ C D S ' F R L —2 0 L O R O M PRE R O M I SCEL L AN E U I S O M . O U S CO . F S A PA ATI NS . U AS — —B f L E N O E E I N O FO M X R TO . e e V L S . AT ST TI S DA UNTAIN I TU ES 7 NICS , n an c nch n a h h s h te e e f an d c ca e e f Wi n e a n d iro d i o ; ypop o p i ;b o ; b , l s a L ACTARTS n d a a . n b e e f w ne n an d cinch n a c ca a c . iro , i , iro o o i y

- r n h r e t P . I xn pe rial t e a ;m och a coffe e ;n e c ta ; Pe rsi a s e b r . UNCHES E xT A T - C u m ia t e e i n e t n i c s u e h o ale R C s. ol b roo b r ; g g r o ; ol bl p — l H o t t o m M a t L M E Fre n h V ie nna . E n . H o a e . . E O N AD s. c ; gg ogg p l

m k sh ak e Pancre tin an d W n e . w ne . Sh e c e Sa at a . i rry obbl r . r og il i ’ ~ m h s h ate Pe s n wi ne and i n e tc Ko la co co c d a I n a t . or i l . ro l p o p p i , ro ,

00 F rmul as. 12mo Cl ot h . 157 Page s, N e arly 5 o . ANEWAMERI CAN BOOK ON I NDUSTRI AL ALCOHOL.

A PRACTI CAL H AN DBOOK ON TH E

ist illat io n of I co h o l

FROM FARM PRODUCTS AN D

" DE N ATU RI N G AL COH OL .

In c u d n h F A c h L aw an d it s Amen dm e n t t h e Go e n l i gt e ree l o ol , v r m e n u n f n d a n u mb e U S e n m e n t t re g lat io s t h e re ore a r of . . gov r a u h z - m n u t ori e d de at u ri g form las.

I n t h e e a at n o f t h s t h e se c n d e d t n t h e aut h h as p r p r io i , o i io , or fo llowe d h is origi n a l p lan o f wri t in g a p lain p ract ica l h an dbook o n t h e m an u fact u re o f a lcoh ol an d de - n at u rin g fo r in du st ria l p u r h n u is un d t o w t o e n m u s t n s po se s . T i s i d st ry bo gro or o p rop or io a s it h as in Ge rman y wh e re ove r ga llon s w e re m an u f e w k fact u re d la st ye ar p rin c ip a lly in sm a ll arm dist ill rie s . Th is or is n o t i n t e n de d as a sc ie n t ific t re at i se b ut as a h e lp t o farm e rs n n u s n a d ot h e rs wi sh i n g t o go i n t o t h is i d t ry o a m ode rat e sca le .

Th e na m a n a u S m e o f h e origi l t t e r h as be e c re f lly re vi se d. o t c h apt e rs re writ t e n an d a ve ry c on side ra ble am o un t o fn e w in form a t n add 2 Th n u m o f illu s r io n e d . e t t a b e t at s b ro u gh t u p t o 60 io o l r ‘

‘ n c u d n a n u m o f at e s n t h e a u o f d st e e s i l i g ber p l givi g l yo t i ill ri .

Conte n s of Ch a t pters. 1 A c h ‘ l S a us f m n d s u c s 2 T n t s a e . h e e a at , l o ol , v rio or o r , p r p r io o f m ash e s an d F m n n m n A 4 e e t at . 3 S e st a at u s. r io , i p l Di illi g p p r , M de n st n A R n n a M . 7 at u s . 5 e ct cat 6 a t o r Di illi g p p r , ifi io , , l i g A c h f m P A n t at e s . 8 c h fr m G a C n Wh e at R ce l o ol ro o o , l o ol o r i , or , , i an d t h e a s A B A Ce e . 9 c f M asse s h f m e e t s . 10 c h m o r r l , l o ol ro , l o ol ro ol an d Su a C n 1 A 2 n a e . 1 h m s n P . h c e . 1 a s e g r , l o olo t ry , Di t illi g l t T ir e n e a a an e m e n an d e u m n 13 - n u A an d t e t . D e at e d c h g r l rr g q ip , r l o ol

‘ A - fi U . S u t h n . ori z e d D e at I irin g D e n atu rin g Re gu lat io n s in t h e n d S In e x . U it t at e s. de

281 a e s 60 illust at ons and ate s 1 2mo . c o th p g , r i pl , , l ,

l I BRARY USE RETURN TO DESK FROM WHI CH BORROWED

LO AN DEPT.

THI S BOOK I S D U E BEFO RE CLO

9 MAY 201197

— L I D 6 2 A 3 0m

— - ( J6 5 3 4 8 1 0 1 9 4 1 2 A A 3 2