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2. Application Guidelines for Aluminum Electolytic Capacitors Application Guidelines for Aluminum Electolytic Capacitors 2. Application Guidelines for Aluminum Electolytic Capacitors 2-1 Application Guidelines ( 8 ) Outer sleeve of the capacitor is not guaranteed as an electrical insulator. Do not use a standard sleeve on 2-1-1. Circuit Design a capacitor in applications that require the electrical ( 1 ) Please make sure the environmental and mounting insulation. When the application requires special conditions to which the capacitor will be exposed to insulation, please contact our sales office for details. are within the conditions specified in catalog or alternate product specification (specification, here ( 9 ) Capacitors shall not be used under the following after). conditions: q(a) Capacitors shall not be exposed to water ( 2 ) Operating temperature and applied ripple current (including condensation), brine or oil. shall be within the specification. (b) Ambient conditions that include toxic gases such qThe capacitor shall not be used in an ambient as hydrogen sulfide, sulfurous acid, nitrous acid, temperature which exceeds the operating chlorine, ammonium, etc.. temperature specified in the specification. (c) Ambient conditions that expose the capacitor to wDo not apply excessive current which exceeds the ozone, ultraviolet ray and radiation. allowable ripple current. wSevere vibration and physical shock conditions that exceed the specification. ( 3 ) Appropriate capacitors which comply with the life requirement of the products should be selected when (10) When designing a circuit board, please pay attention designing the circuit. to the following: qHave the hole spacing on the P.C. board match the ( 4 ) Aluminum electrolytic capacitors are polarized. Do lead spacing of the capacitor. not apply reverse voltage or AC voltage. Please use wThere should not be any circuit pattern or circuit wire bi-polar capacitors for a circuit that can possibly see above the capacitor pressure relief vent. reversed polarity. eUnless otherwise specified, following clearance Note: Even bi-polar capacitors can not be used for should be made above the pressure relief vent. AC voltage application. Case Diameter Clearance Required φ6.3~16 2mm or more ( 5 ) Do not use aluminum electrolytic capacitors in a φ18~35 3mm or more circuit that requires rapid and very frequent charge / φ40 or more 5mm or more discharge. In this type of circuit, it is necessary to use rIn case the vent side is placed toward P.C. a specially designed capacitor with extended life board(such as end seal vented parts), make a characteristics. corresponding hole on the P.C. board to release the gas when vent is operated. The hole should be ( 6 ) Do not apply excess voltage. made to match the capacitor vent position. qPlease pay attention so that the peak voltage, which tDo not install screw terminal capacitor with end seal is DC voltage overlapped by ripple current, will not side down. When you install a screw terminal exceed the rated voltage. capacitor in a horizontal position, the positive wIn the case where more than 2 aluminum electrolytic terminal must be in the upper position. capacitors are used in series, please make sure that applied voltage will be lower than rated voltage and (11) The main chemical solution of the electrolyte and the the voltage be will applied to each capacitor equally separator paper used in the capacitors are using a balancing resistor in parallel with the combustible. The electrolyte is conductive. When it capacitors. comes in contact with the P.C. board, there is a possibility of pattern corrosion or short circuit ( 7 ) Aluminum electrolytic capacitors must be electrically between the circuit pattern which could result in isolated as follows: smoking or catching fire. q(a) Case and negative terminal (except axial leaded Do not locate any circuit pattern beneath the part such as JIS style symbol 02 type) capacitor end seal. (b) Case and positive terminal (c) Case and circuit pattern (12) Do not design a circuit board so that heat generating w(a) Auxialiary terminal of can type such as JIS style components are placed near an aluminum electrolytic symbol 693, 694 or 695 and negative and capacitor or reverse side of P.C. board (under the positive terminal, including the circuit pattern. capacitor). (13) Please refer to the pad size layout recommendations in specification when designing in surface mount capacitors. TECHNICAL NOTES CAT.8101C NICHICON CORPORATION Application Guidelines for Aluminum Electolytic Capacitors (14) Electrical characteristics may vary depending on (11) Please pay attention to that the mechanical shock to changes in temperature and frequency. Please the capacitor by suction nozzle of the automatic consider this variation when you design circuits. insertion machine or automatic mounter, or by product checker,or by centering mechanism. (15) When you mount capacitors on the double-sided P.C. boards, do not place capacitors on circuit patterns or (12) Hand soldering. over on unused holes. qSoldering condition shall be confirmed to be within the specification. (16) The torque for terminal screw or brackets screws shall Bit temperature: 350 10oC 1 be within the specified value in the specification. Application time of soldering iron: 3 0 second w If it is necessary that the leads must be formed due (17) When you install more than 2 capacitors in parallel, to a mismatch of the lead space to hole space on consider the balance of current flowing through the the board, bend the lead prior to soldering without capacitors. applying too much stress to the capacitor. e If you need to remove parts which were soldered, (18) If more than 2 aluminum electrolytic capacitors are please melt the solder enough so that stress is not used in series, make sure the applied voltage will be applied to lead. lower than the rated voltage and that voltage will be rPlease pay attention so that solder iron does not applied to each capacitor equally using a balancing touch any portion of capacitor body. resistor in parallel with each capacitor. (13) Flow soldering (Wave solder) qAluminum capacitor body must not be submerged 2-1-2. Mounting into the solder bath. Aluminum capacitors must be ( 1 ) Once a capacitor has been assembled in the set and mounted on the "top side" of the P.C. board and only power applied, do not attempt to re-use the capacitor allow the bottom side of the P.C. board to come in in other circuits or application. contact with the solder. wSoldering condition must be confirmed to be within ( 2 ) Electric potential between positive and negative the specification. o terminal may exist as a result of returned Solder temperature: 260 5 C, Immersing lead electromotive force, so please discharge the time:10 1 second, Thickness of P.C. board : capacitor using a 1kΩresistor. 1.6mm ePlease avoid having flux adhere to any portion ( 3 ) Leakage current of the parts that have been stored except the terminal. for more than 2 years may increase. When leakage rPlease avoid contact between other components current has increased, please perform a voltage and the aluminum capacitor. treatment using 1kΩresistor. (14) Reflow soldering (SMD only) ( 4 ) Please confirm ratings before installing capacitors on qSoldering condition must be confirmed to be within the P.C. board. the specification. Pre-heationg : Less than 150oC, 90 seconds max. ( 5 ) Please confirm polarity before in stalling capacitors Max. temperature at capacitor top during reflow : o on the P.C. board. 230 C The duration for over 200oC temperature at ( 6 ) Do not drop capacitors on the floor, nor use a capacitor top: 20 seconds max. capacitor that was dropped. The duration from the pre-heat temperature to peak temperature of reflow varies due to changes of the ( 7 ) Do not damage the capacitor while installing. peak temperature. wWhen an infrared heater is used, please pay ( 8 ) Please confirm that the lead spacing of the capacitor attention to the extent of heating since the matches the hole spacing of the P.C. board prior to absorption rate of infrared, will vary due to installation. difference in the color of the capacitor body, material of the sleeve and capacitor size. ( 9 ) Snap-in can type capacitor such as JIS style symbol eThe number of reflow time for SMT aluminum 692, 693, 694 and 695 type should be installed tightly electrolytic capacitors shall be one time. If this to the P.C. board (allow no gap between the P.C. type of capacitor has to be inevitably subjected to board an bottom of the capacitor). the reflow twice, enough cooling time between the first and second reflow (at least more than 30 (10) Please pay attention that the clinch force is not too minutes) shall be taken to avoid consecutive reflow. strong when capacitors are placed and fixed by an Please contact our sales office if you have automatic insertion machine. questions. TECHNICAL NOTES CAT.8101C NICHICON CORPORATION Application Guidelines for Aluminum Electolytic Capacitors (15) Do not tilt lay down or twist the capacitor body after 2-1-6. Storage the capacitor are soldered to the P.C. board. ( 1 ) Do not keep the capacitor in high temperature and high humidity. (16) Do not carry the P.C. board by grasping the Storage ambient should be; soldered capacitor. Temperature : 5oC~35oC, Humidity : less than 75%. Place: Indoor (17) Please do not allow anything to touch the capacitor after soldering. If P.C. board are stored in a stack, ( 2 ) Avoid enviroment conditions: where capacitors can please make sure P.C. board or the other be covered with water, brine or oil. components do not touch the capacitor. The capacitors shall not be effected by any radiated ( 3 ) Avoid ambient conditions: where capacitors are heat from the soldered P.C. board or other exposed to poisonous gases such as hydrogen components after soldering.
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