DOCSLIB.ORG

Fuse Sizing Guide

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Fuse Sizing Guide FUSE SIZING GUIDE PRACTICAL APPLICATION INFORMATION This guide is a general recommendation and does not include the many variables that can exist for specific situations such as special local codes, unusual temperature or other operating conditions, N.E.C. demand factors, conductor derating, etc. Recommended U.L. Current Limiting Fuse Classes & EDISON Fusegear Symbols:* Time-Delay Type Class L –LCL –600VAC or less: 601-6000A Class RK1 –LENRK –250VAC or less: 6/10-600A –LESRK –600VAC or less: 1/2-600A Class RK5 –ECNR –250VAC or less: 1/10-600A –ECSR –600VAC or less: 1/10-600A Class J –JDL –600VAC or less: 1-600A Class CC –HCTR –600VAC or less: 1/4-10A Fast-Acting Type (Non/time-delay) Class T –TJN –300VAC or less: 1-800A –TJS –600VAC or less: 1-800A Class L –LCU –600VAC or less: 601-6000A Class RK1 –NCLR –250VAC or less: 1-600A –SCLR –600VAC or less: 1-600A Class J –JFL –600VAC or less: 1-600A Class CC –HCLR –600VAC or less: 1/10-30A *The fuse classes shown are U.L. Listed as “current limiting” with 200,000 RMS symmetrical amperes interrupting rating. Classes J and L are not interchangeable with fuses having lower l.R.. Class R fuses require Class R rejection fuse clips to prevent interchangeability with Classes H and K fuses with lower interrupting rating. (N.E.C. 110-9 and 240-60b.) Figure 1 1 Main Service Conductor Cable 4 Branch Circuit Fuse d) 150% of the nameplate current Limiters (N.E.C. 240, 450-6): Size, No Motor Load rating of the largest continuous-duty a) Select by cable size and mounting (N.E.C. 240-3, 220-3):* motor. Add to “a)” above. terminal configurations required. a) 100% of non-continuous load. e) 125% of the nameplate current *Do not exceed conductor ampacity. rating of other continuous duty motors. 2 Main Service Circuit Recommended fuses: LENRK, ECNR, Fuses–Mixed Loads: NCLR, JDL, LCU, or LCL. Add to “a)” above. a) Size fuses same as item 6. 5 Branch Circuit Fuse Size, No f) Recommended fuses: LENRK/LESRK, 3 Transformer Circuit Fuses Motor Load JDL, ECNR/ ECSR, LCU, LCL. (N.E.C. 450-3b, 240-3, 240-21, (N.E.C. 240-3, -220-3):* *Do not exceed conductor ampacity. 384-16d, 430-72b Ex. 3, 4 & (c) a) 125% of continuous load. Fuse may be 7 Feeder Circuit Fuse Size, 100% as required):* sized 100% when used with a continuous Motor Load (N.E.C. 240-3, 220- a) PRIMARY FUSES: Size fuses not over rated switch. Recom-mended fuses 10b, 430-24):* 125%. As exceptions exist, refer to the same as 4. a) Determine non-continuous appropriate N.E.C. paragraphs. *Do not exceed conductor ampacity. motorload (N.E.C. 430-22a Ex. 1). Recommended fuses: LESRK, ECSR, JDL, 6 Feeder Circuit Fuse Size, b) Determine load of A/C or LCL+.* Mixed Load refrigeration equipment (N.E.C. 440-3, b) SECONDARY FUSES (Sum of (N.E.C. 220-10b, 240-3, 430-22a -5, -12). Add to “a)” above. following): 125% of the continuous load Ex. 1, 430-24):* c)150% of nameplate current rating of plus 100% of non-continuous load. Fuse a) 100% of non-continuous, non-motor the largest continuous duty motor. Add size not to exceed 125% of transformer load plus 125% of continuous, non- to “a)” above. secondary rated amps. RECOMMENDED motor load d)125% of the other continuous-duty FUSES: LENRK, ECNR, NCLR, JDL or b) Determine non-continuous motor load motors. Add to “a)” above. LCU. (N.E.C. 430-22a EX. Add to “a)” above. *Fuse size must not exceed ampacity of e)Recommended fuses: LENRK/LESRK, conductors. Where selectivity is desired, c) Determine A/C or refrigeration load. JDL, ECNR/ ECSR or LCL. refer to EDISON selectivity methods. (N.E.C. 440-3b). Add to “a)” above. *Do not exceed conductor ampacity. Z-106 PRACTICAL APPLICATION INFORMATION Levels of Government regulations and ordinances, from Federal to local, usually base acceptable safe performance and application of fuses and circuit breakers on the National Electrical Code. The NEC commonly refers proven safe performance to the Standards of 8 Branch Circuit Fuse Size, Individual Motor Load, Safety of Underwriters Laboratories, Inc. The NEC is sponsored by With Fuse Overload Protection (No Starter the National Fire Protection Association. Overload Relays): (N.E.C. 430-32, 430-36): Therefore, fuses manufactured to meet the same standards of a) Motors with 1.15 Service Factor or temperature rise not U.L. testing and “Listing” for specific types are physically and over 40 Degrees C., size fuses at not more than 125% of the electrically interchangeable, based on the standards, regardless motor nameplate current rating. of brand. b) Best protection is obtained by measuring motor running Fuses can be designed and manufactured to higher standards than current and sizing fuses at 125% of measured the minimum standards required to pass U.L. testing to current for normal motor operation. Reference be “Listed”. to “Average Time/Current Curves” is recommended. For all of the reasons above, Edison Fuses Inc. manufactures d) Recommended Fuses: LENRK/LESRK, JDL, or ECNR/ECSR . fuses not only to meet industry standards, but also to reach the 9 Branch Circuit Fuse Size, Individual Motor Load, highest quality standards found in the industry. With Starter Overload Relays (N.E.C. 430-32, 430-52): National Electrical Code a) For “back-up” N.E.C. overload, ground fault and short- The National Electrical Code (N.E.C.) is sponsored by the National circuit protection size the fuses the same as (8 a, b) above, or Fire Protection Association. This Code is adopted as the MINIMUM the next standard size larger. standard for public safety by the federal government, states, counties, cities and many private organizations. Enforcement is b) The fuse sizes in a) above may be increased as allowed by usually the responsibility of Professional Electrical Inspectors NEC references. Generally, dual element fuses should not exceed 175% of motor nameplate F.L.A. and non-U.L. defined provided with enforcement authority. time-delay fuses not more than 300%. Fuse Ratings c) Recommended fuses: LENRK/LESRK, JDL, ECNR/ ECSR or LCL. 10 Fuse Sizing for Individual Large Motors With F.L.A. Above 480 Amps or Otherwise Require Class L Fuses - (N.E.C. 430-52): Application Tips 1. Size fuses as closely as practical to the ampacity of the protected circuit components without the probability of Fuses with an A-C voltage rating may be applied at system unnecessary fuse opening from harmless, transient current voltages below the fuse voltage rating, but not at voltages above surges. This usually requires a choice between time-delay and the fuse voltage rating. The other A-C fuse ratings remain the non-time-delay fuses. same at applied voltages below the fuse voltage rating. 2. Use Class R fuse clips with Class R fuses to prevent installation A-C rated fuses should not be applied in D-C voltage circuits of fuses with less interrupting rating or current limitation. Class H unless D-C application ratings are provided by the fuse fuse reducers cannot be used with Class R fuse clips. manufacturer. Except for some special purpose fuses, D-C ratings 3. When a conductor is oversized to prevent excess voltage drop, are not usually shown on fuse labels. size the fuses for the ampacity of protected circuit components EDISON Time/Current Curves, Peak Let-Through Curves are based instead of oversizing fuses for the larger conductor. on 60 Hertz A-C data. The operating frequency (Hertz) will affect fuse characteristics in Safety various ways. Industry PUBLIC SAFETY standards that apply to overcurrent Time/Current Curves will not shift and fuse ratings will not change protection devices (OPD), fuses and circuit breakers, are intended from 1-100 Hertz in normal applications. If ferrous hardware is to apply to both types of devices. The use of these devices serves used to mount the fuses, eddy current heating could alter the public safety which includes all aspects of fuse or circuit breaker ratings. performance and dependability. Above 100 Hertz, “skin effect” could alter the fuses’ rating Any industry requirements that apply to fuses apply equally to characteristics. This effect must be analyzed on an individual circuit breakers. Industry standards do not intend any deliberate application basis. compromises for public safety. Z-107 PRACTICAL APPLICATION INFORMATION FUSE RATINGS, CONT. Other characteristics shown on fuse labels such as “interrupting rating”, “current limiting”, “time-delay”, “fast-acting” and Correction Factors for Edison Fast-Acting and Non- (1) Underwriters Laboratories, Inc. (U.L.) Class are described DelayCorrection Fuses Factors for Edison Fast-Acting and Non- Delay Fuses(1) elsewhere. Ambient Celsius Maximum Load Current Fuse labels show “certification” or “listing” logo’s when applicable. TemperaturesAmbient Celsius (%Maximum of Rating) Load Current Such logo’s may be: -20Temperatures to -40 93%(% of Rating) -19-20 to to -1 -40 90%93% • “U.L.” (U.L. “Listed”) zero-19 to -124 86%90% • “CSA” (Canadian Standards Association “certified”) 25zero to to60 24 80%86% 6125 to to 80 60 60%80% • (U.L. Recognized) 8161 to to 100 80 45%60% (1) Such logos mean that the fuse meets the performance standards Fuses installed81 to 100 in an enclosure with a base loading45% of 80% as required by the National(1) Electrical Code. Contact Edison Fuses Inc. for other conditions. of these safety organizations. Fuses installed in an enclosure with a base loading of 80% as required by the National Electrical Code.
Load more

Recommended publications
  • 2020 National Electrical Code® Style Manual
    2020 NATIONAL ELECTRICAL CODE® STYLE MANUAL 1 FOREWORD August 2020 The National Electrical Code® is used nationally and internationally as the basis for safeguarding persons, buildings, and their contents from hazards arising from the use of electricity. It is vitally important that the text be as explicit as possible, and that maximum consistency be achieved in the language used in the text. The Code contains those provisions considered necessary for safety and thus is widely used as a basis for legal enforcement in the installation of electrical conductors and equipment in buildings and certain other premises (as detailed in the Code itself); this places a major responsibility on those involved in the preparation of document text to use forms of expression that promote uniform interpretation. The National Electrical Code Correlating Committee has recognized these responsibilities and has issued this manual. Preparation and Date of Adoption. This manual was originally prepared by the Editorial Task Group of the National Electrical Code Committee and adopted by the National Electrical Code Correlating Committee on May 13, 1969. It was amended September 22, 1975, October 11, 1984, October 12, 1989, and May 9, 1994. In January 1999, the Correlating Committee Task Group on the Usability of the NEC rewrote the manual. It was adopted by the National Electrical Code Correlating Committee on March 19, 1999 and by the Standards Council on April 15, 1999. It was amended March 1, 2001, January 15, 2003, and August 9, 2011, August 2015, and December 2020. 2 TABLE OF CONTENTS Foreword ........................................................................................................ 2 Chapter 1 General 4 1.1 Purpose ............................................................................................
    [Show full text]
  • Electrical Inspection Checklist for One-Family Homes Based on the 2020 National Electrical Code® (NEC®)
    Electrical Inspection Checklist for One-Family Homes Based on the 2020 National Electrical Code® (NEC®) NOTE: The Board of Electricity adopted the 2020 National Electrical Code (NEC) with an effective date of Nov. 17, 2020. Accordingly, the Department of Labor and Industry began enforcing the 2020 NEC on Nov.17, 2020. Electrical work authorized by permits issued on or after this date must comply with the 2020 NEC. Electrical license examinations are based on the requirements of the 2020 NEC beginning Jan. 1, 2021. However, due to concerns regarding the availability of 2-pole GFCI circuit breakers, the department delayed enforcement of the requirements for 250-volt GFCI receptacles and outlet requirements found in NEC 210.8(A) and 210.8(F). On April 5, 2021, DLI will begin enforcing the 250-volt GFCI receptacle and outlet requirements found in NEC 210.8(A) and 210.8(F). Industry circuit breaker manufacturers have confirmed that supply-chain challenges will be resolved in March 2021. Electrical work authorized by permits issued on or after April 5, 2021, must comply with the 2020 NEC. 001 An owner (i.e. homeowner) who files a Request for Electrical Inspection form (i.e. permit) with the Department of Labor and Industry or other electrical inspection authority is signing an affidavit and declaring they own and occupy the residence and they will personally perform all of the electrical work, including the planning and laying out of the electrical work. 002 The term “owner” is defined in law as a natural person who physically performs electrical work on premises the person owns and actually occupies as a residence or owns and will occupy as a residence upon completion of construction.
    [Show full text]
  • Three-Phase Power Capacitor with Fuse Protection
    Power capacitors, LV CSB-F Three-phase power capacitor with fuse protection Description Features Features The application of new technologies to ma- Operating voltage 230, 400 V (for other voltages, please ask) nufacture prismatic capacitors have allowed Support voltage 400 V 440 V CIRCUTOR to reinvent the classic CS capa- Capacity tolerance ± 10% citor, manufactured for over 35 years. CS Capacitor + General protection fuses of the Unit composed of NH-00 type with high rupture power (HRP) The spirit of innovation and proprietary te- Insulation level 3 / 15 kV chnology used during the design of the new Discharge resistance 75 V / 3 minutes CSB capacitor have increased the lifespan of Overcurrent 1.3 times the rated current permanently traditional prismatic capacitors by over 60%. 10% 8 over 24 hours 15% up to 15 minutes over 24 hours Overvoltage This new series has improved all aspects of 20% up to 5 minutes over 24 hours the previous models, offering our customers 30% up to 1 minutes over 24 hours a longer-lasting, safer and more profitable Frequency 50 or 60 Hz • Dielectric < 0.2 W / kvar capacitor. Losses: • Total < 0.5 W / kvar • Dielectric regeneration • Internal fuse Protections • Overpressure system Application • Vermiculite Construction features • M6 for CV, M10 for CQ, CSB, Its application is mainly based on the com- • Power rating Terminals: CSB-6B, CFB, CFB-6B • Earth pensation of transformers and motors. In • M6 general, they are used for the compensation • CV 5 Nm Torque value of installations with constant loads. • CQ, CSB,
    [Show full text]
  • FSW Fuse-Switch-Disconnectors
    Motors | Automation | Energy | Transmission & Distribution | Coatings FSW Fuse-Switch-Disconnectors www.weg.net Fuse-Switch-Disconnectors The FSW Fuse-Switch-Disconnectors, developed according to International Standard IEC 60947-3 and bearing CE certification, are applied in electric circuits in general so as to provide the disconnection and protection against short circuits and overloads by means of NH blade contact fuses. In order to ensure a long lifespan, the FSW Fuse-Switch-Disconnectors are manufactured with reinforced thermoplastic materials and flame retardant. Additionaly, they feature contacts with silver coating, providing low power losses. Safety and Simplicity WEG switch-disconnector has several characteristics which aim at increasing security for operation and maintenance of the equipment, simplifying diagnoses and fuse replacement: g The switch-disconnector allows checking the state of the fuses through a transparent cover, besides featuring small openings which allow making electrical measurements without interrupting the operation. g As per IEC 60947-3, the switch-disconnector can perform the non- frequent opening under load. The FSW series has arc chambers for the extinction of the electric arc and disconnects all the phases together, ensuring full insulation between the load circuit and power supply. g In the opening of the switch-disconnector, the fuses remain fixed to the cover, preventing their drop or accidental contact between the energized parts. Furthermore, the cover is totally removable, allowing simple fuse replacement in a simple and safe area out of the electrical panel. g The switch-disconnectors also feature a built-in auxiliary contact in order to indicate when they are open or not properly closed.
    [Show full text]
  • AN-Mersen-Application-Information-Capacitor-Protection.Pdf
    CAPACITOR APPLICATION INFORMATION PROTECTION The primary responsibility of a capacitor fuse is to For applications 600V or less in lieu of specific fusing isolate a shorted capacitor before the capacitor can recommendations from the capacitor manufacturer, damage surrounding equipment or personnel. Typical we suggest a Mersen A60C Type 121 or an A6Y Type capacitor failure occurs when the dielectric in the 2SG fuse sized at 165% to 200% of the capacitor’s capacitor is no longer able to withstand the applied current rating (contact factory for technical data). If voltage. A low impedance current path results. The these fuses are not dimensionally acceptable, then excessive heat generated builds pressure and can a non-time delay Class J or Class RK1 fuse could be cause violent case rupture. A fuse will isolate the used and sized at 185% to 220% of the capacitor’s shorted capacitor before case rupture occurs. current rating. For applications over 600V to 5.5kV, we suggest FUSE PLACEMENT Amp-Trap A100C to A550C capacitor fuses. These The Code requires that an overcurrent device be medium voltage fuses are available in a variety of placed in each ungrounded conductor of each voltage ratings and mounting configurations. Refer capacitor bank (see Figure 1). The Code further to Section MV for specific data. Medium voltage requires that the rating or setting of the over- capacitor fuses are sized at 165% to 200% of the current device be as low as practicable. A separate capacitor current rating. overcurrent device is not required if the capacitor is Capacitor fuses are selected for their ability to connected on the load side of a motor-running provide short circuit protection and to ride through overcurrent device.
    [Show full text]
  • Electrical Code Amendment
    CITY OF GRAPEVINE Chapter 7, Buildings and Construction, Article III, Electrical Code ARTICLE III. ELECTRICAL CODE DIVISION 1. GENERALLY Sec. 7-30. Definitions. For the purposes of this article, hereinafter referred to as the electrical code or this code, the following terms, phrases, words, and their derivatives shall be construed as set out in this section: Approved: Acceptable to the building inspection division and/or the electrical board of appeals of the city. Authorized person: Any person, as defined in section 1-5, registered or licensed under the provisions of this code to do work as permitted under the specific provisions of this code. Buildings, building use: Words relating to buildings and building use, when not otherwise separately defined, shall have meanings which conform to the meanings set out in the zoning ordinance of the city; otherwise, they shall have their usual dictionary meanings. City: The territory within the corporate limits of the city, or the legally constituted governing body thereof, its agents and its officers. Conductor: A wire or cable or other form of metal suitable for carrying electric current or potential. Electrical apprentice: Any person who has been issued a license from the State of Texas as an electrical apprentice as provided for by state law. Electrical construction: All work and materials used in installing, maintaining, or extending a system of electrical wiring and all appurtenances, apparatus or equipment used in connection therewith, inside or outside of or attached to any building, structure, lot or premises. Electrical contractor: Any person who has been issued a license from the State of Texas as an electrical contractor as provided for by state law.
    [Show full text]
  • SMD Power Inductors At-A-Glance Your One Source for Wire Wound Magnetic Solutions
    Worldwide Presence Engineering Expertise Leading Edge Technology Award Winning Support Our Commitment to Quality SMD Power Inductors At-A-Glance Your one source for wire wound magnetic solutions 2,700 Standard P/Ns to Choose From Inductance Range 0.01uH to 10mH DC Current Range 4mA to 70A DC Resistance Range 2mW to 140W Height Range 1mm to 12.3mm Custom Formulated Powder Materials High Efficiency +1 866.239.5777 signaltransformer.com MEDICAL Signal Transformer wire wound SMD Inductors have Diagnostic Surgical Equipment found their way into every market segment Patient Monitoring Hand Held Devices Surgical Generators In-Home Dialysis SC1206, SC1210, SC1812, SC2220 Series Blood Analyzers • 0.1uH to 10mH Inductance • 2mm to 5mm Height NETWORKING • 0.05A to 7.8A Saturation Current Data Center Switching Routers SC31 to SC108 SERIES — Unshielded Servers & Server I/O Server Blades • 0.8uH to 1.2mH Inductance 100G Core Switches • 1.8mm to 8.3mm Height NIC Cards • 0.03A to 4.7A Saturation Current 3U Top Rack & End of Rack 40G Firewall Patch Panels & Wiring SC33xxF SERIES — Unshielded Closet • 1.0uH to 1.0mH Inductance • 3mm to 11.43mm Height TELECOM/DATACOM • 0.1A to 18.0A Saturation Current Set-Top Boxes Hard Drives Laptops SC52LC & BC53LC Series — Shielded Printers • 1.2uH to 220uH Inductance Plotters • 2mm to 3.0mm Height Telephone Line Switching PBX • 0.18A to 2.92A Saturation Current Current Line Detection SCRH SERIES — Magnetically Shielded • 1.0uH to 180uH Inductance CONSUMER Digital Cameras • 1.9mm to 4mm Height Video Recorders • 0.15A
    [Show full text]
  • Don't Be Confused by Your Fuse
    Head Office Neptronic® 400 Lebeau Blvd. HVAC Controls Electric Actuators Actuated Valves Montreal, Quebec, Canada H4N 1R6 Tel.: (514) 333-1433 Humidifiers Electric Heaters Fax: (514) 333-3163 Toll Free: 1-800-361-2308 Don’t be confused by your fuse: MCA and MOP for your humidifier explained Before we start, we need first to understand what MCA and MOP are. The minimum circuit ampacity (MCA) and maximum overcurrent protection (MOP) ratings provide a guide for safely connecting field-wired equipment to the building mains. Understanding these ratings, and their relationship to each other, is critical to properly selecting wire and circuit breaker sizes. What is MCA? Minimum Circuit Ampacity (MCA) is a calculated value that specifies the minimum main power wire size. It is also used to determine the minimum wire size required for a field wired product. This specification is necessary in order to guarantee that the wiring will not overheat under expected operating conditions. The wire size takes into account the normal current draw, aging of components and anticipated faults. More specifically, the MCA is the highest steady-state electrical current that the unit should see when operating correctly. What is MOP? Maximum Over-Current Protection (MOP) is a calculated value that determines the maximum size of the over-current protection device (fuse or breaker). There are different MOP equations depending on your application. The maximum overcurrent protection (MOP) is the maximum circuit breaker size required to properly protect the equipment under anticipated fault conditions. The MOP takes into account startup surges and component aging. Supply wiring must be rated to carry the amps shown as MCA.
    [Show full text]
  • Principles of Shunt Capacitor Bank Application and Protection
    Principles of Shunt Capacitor Bank Application and Protection Satish Samineni, Casper Labuschagne, and Jeff Pope Schweitzer Engineering Laboratories, Inc. Presented at the 64th Annual Georgia Tech Protective Relaying Conference Atlanta, Georgia May 5–7, 2010 Previously presented at the 63rd Annual Conference for Protective Relay Engineers, March 2010, and 9th Annual Clemson University Power Systems Conference, March 2010 Originally presented at the 36th Annual Western Protective Relay Conference, October 2009 1 Principles of Shunt Capacitor Bank Application and Protection Satish Samineni, Casper Labuschagne, and Jeff Pope, Schweitzer Engineering Laboratories, Inc. Abstract—Shunt capacitor banks (SCBs) are used in the electrical industry for power factor correction and voltage support. Over the years, the purpose of SCBs has not changed, but as new dielectric materials came to market, the fusing practices for these banks changed from externally fused to internally fused, fuseless, and finally to unfused [1]. This paper gives a brief overview of the four most common types of SCBs. What are the differences between them? Which is the best one to use? What type of protection is best suited for each bank configuration? The paper provides a quick and simple way to calculate the out-of-balance voltages (voltage protection) or current (current protection) resulting from failed capacitor units or elements. While the identification of faulty capacitor units is easy with an externally fused bank, it is more complex with the other types of fusing, making maintenance and fault investigation difficult. This paper presents a novel method to identify the faulted phase and section in capacitor banks. Fig. 1. Four most common capacitor bank configurations I.
    [Show full text]
  • 2018 Canadian Electrical Code Saskatchewan Interpretations
    120 Based on the 2018 Canadian Electrical Code Effective: January 1, 2019 V4.2 (this page left intentionally blank) ELECTRICAL INSPECTIONS Preface and Scope The Canadian Electrical Code, Part l, Twenty-Fourth Edition, as interpreted by these requirements, issued under Section 5 of The Electrical Inspection Act, 1993, shall govern the workmanship and all other matters pertaining to electrical equipment and the installation of electrical equipment in or upon any land, buildings, structures, and premises. All previously issued bulletins are superseded by these interpretations. This document contains supplementary information to clarify the requirements of the 24th edition of the Canadian Electrical Code (CEC), and by their inclusion herein is adopted as requirements under Section 5 of The Electrical Inspection Act, 1993. Report of Accident The Electrical Inspection Act, 1993 c.E-6.3 s.27 requires: “Where an accident involving an electrical installation or electrical equipment occurs and results in a death or injury of a person or in a fire or an explosion, the contractor or the contractor’s agent or the owner of the electrical equipment or the owner’s agent shall immediately notify the Chief Electrical Inspector, stating the precise location of the accident, its general nature and results”. Investigation of Accident The Electrical Inspection Act, 1993 c.E-6.3 s.28 requires: The accident site is to be preserved, “no part of any electrical plant or electrical equipment involved is to be removed or its position altered by any person”, “until the written permission of an Inspector has been obtained”. 2018 Saskatchewan Interpretations Page 1 ELECTRICAL INSPECTIONS Table of Contents PREFACE AND SCOPE ..................................................................................................................................................
    [Show full text]
  • POWR-GARD Technical Application Guide
    Application Guide POWR-GARDTechnical Application Guide This Technical Application Guide or ‘Fuseology’ provides the information needed to select the correct types of Littelfuse POWR-GARD® fuses for most applications. If there are any questions or if additional data is needed for a specific use, call the Littelfuse Technical Support and Engineering Service Group at 1-800-TEC-FUSE (1-800-832-3873), email them at [email protected] or visit us at littelfuse.com. TECHNICAL APPLICATION GUIDE Table of Contents Fuseology Fundamentals ............................................................... 3 Selection Considerations ............................................................... 5 Time-current Curves and Peak Let-through Charts ........................ 9 Selective Coordination ..................................................................11 UL/CSA Fuse Classes and Applications ........................................14 Technical Information Terms and Definitions ...................................................................16 White papers, and a library of technical information is Motor Protection Tables ............................................................... 23 available online at littelfuse.com/technicalcenter UL Fuse Classes & Selection CHart ............................................ 26 Condensed Fuse Cross Reference .............................................. 27 littelfuse.com 2 © 2017 Littelfuse POWR-GARD® Products Technical Application Guide FUSEOLOGY FUNDAMENTALS I. OVERCURRENT PROTECTION 3. Minimizes
    [Show full text]
  • Wiring a Wall Section
    Youth Explore Trades Skills Electrician Wiring a Wall Section Description The activities that have led up to wiring a wall should have given students the skills and knowledge to culminate with this activity. This activity could be an opportunity to conduct a summative assessment of students’ previous knowledge of theory, safety, code, and wiring methods. Wiring a wall section will introduce students to a few new CEC rules and wiring methods. Having a wall section is obviously a requirement for this activity. The wall section could be full scale or smaller; to make this activity relate to the real world, it’s recommended that the wall section be at least 4' wide by 4' tall. The wall section shown in Figure 1 would be optimal, as it has some real (although scaled down to half size) features such as door and window openings, as well as a corner section, which will help students learn about routing wire and placement of device boxes in relation to these features. Figure 1—Sample wall section Building a wall section for a class requires a substantial amount of lumber and time. Optimally, this activity would work well with students having completed the carpentry portion of the course first. This activity is an opportunity for students to wire a wall to code specifications and with the teacher’s supervision, energize and test their circuits. Students will likely work in small groups, depending on the availability of material and the number of walls available. The students should have the opportunity to wire their wall sections individually, to give the teacher a clear picture of each student’s skills and competencies.
    [Show full text]