NTC thermistors for inrush current limiting Leaded and coated disks Series/Type: B57236 Date: May 2009 © EPCOS AG 2009. Reproduction, publication and dissemination of this publication, enclosures hereto and the information contained therein without EPCOS' prior express consent is prohibited.
Inrush current limiters B57236 ICLs S236 Applications Switch-mode power supplies Dimensional drawing Features Useable in series connections up to 265 VRMS Coated thermistor disk Kinked leads of tinned copper wire Wide resistance range UL approval (E69802) Options Resistance tolerance <20% and alternative lead configurations available on request Dimensions in mm Approx. weight 1 g Delivery mode Bulk (standard), cardboard tape, reeled or in Ammo pack General technical data Climatic category Max.
Inrush current limiters B57236 ICLs R25 Ω 80 120 S236 Imax (0...65 °C) A 1.6 1.5 B25/100 K 3300 3450 Ctest1) 230 V µF 400 400 Ctest1) 110 V µF 1600 1600 Param. for R(I)1) k 1.64 1.74 Param. for R(I)1) n 1.37 1.
Inrush current limiters B57236 ICLs S236 Taping and packing 1 Taping of radial leaded NTC thermistors Dimensions and tolerances Lead spacing F = 5.0 mm (taping to IEC 60286-2) Lead spacing F = 7.5 mm (taping based on IEC 60286-2) Please read Cautions and warnings and Important notes at the end of this document.
Inrush current limiters B57236 ICLs S236 Dimensions (mm) Lead spacing 5 mm w 11.5 Tolerance of lead spacing 5 mm max. Lead spacing 7.5 mm 21 Tolerance of lead spacing 7.5 mm max. th 6.0 max. 7 max. d 0.5/0.6 ±0.05 0.8/1.0 ±0.05 P0 12.7 ±0.3 12.7 ±0.3 P1 3.85 ±0.7 8.95 ±0.8 F 5.0 +0.6/ 0.1 7.5 ∆h 0 ±2.0 0 ∆p 0 ±1.3 0 ±2.0 W 18.0 ±0.5 18.0 ±0.5 W0 5.5 min. 11.0 min. W1 9.0 +0.75/ 0.5 9.0 +0.75/ 0.5 ±1 mm / 20 sprocket holes ±0.
Inrush current limiters B57236 ICLs S236 Types of packing Ammo packing Ammo type x y z I 80 240 210 II 56 355 355 Ammo type II only for ICL types S237 and S238 Packing unit: 1000 - 2000 pcs./reel Reel packing Packing unit: 1000 - 2000 pcs./reel Reel dimensions (in mm) Reel type d f n w I 360 max. 31 ±1 approx. 45 54 max. II 500 max. 23 ±1 approx. 59 72 max. Please read Cautions and warnings and Important notes at the end of this document.
Inrush current limiters B57236 ICLs S236 Bulk packing The components are packed in cardboard boxes, the size of which depends on the order quantity.
Inrush current limiters B57236 ICLs S236 Mounting instructions 1 Soldering 1.1 Leaded NTC thermistors Leaded thermistors comply with the solderability requirements specified by CECC. When soldering, care must be taken that the NTC thermistors are not damaged by excessive heat. The following maximum temperatures, maximum time spans and minimum distances have to be observed: Dip soldering Iron soldering Bath temperature max. 260 °C max. 360 °C Soldering time max. 4 s max.
Inrush current limiters B57236 ICLs S236 Wave soldering Temperature characteristic at component terminal with dual wave soldering 2 Robustness of terminations The leads meet the requirements of IEC 60068-2-21. They may not be bent closer than 4 mm from the solder joint on the thermistor body or from the point at which they leave the feedthroughs. During bending, any mechanical stress at the outlet of the leads must be removed. The bending radius should be at least 0.75 mm.
Inrush current limiters B57236 ICLs S236 When subjecting leads to mechanical stress, the following should be observed: Tensile stress on leads During mounting and operation tensile forces on the leads are to be avoided. Bending of leads Bending of the leads directly on the thermistor body is not permissible. A lead may be bent at a minimum distance of twice the wire's diameter +2 mm from the solder joint on the thermistor body. During bending the wire must be mechanically relieved at its outlet.
Inrush current limiters B57236 ICLs S236 Cautions and warnings General See "Important notes" at the end of this document. Storage Store thermistors only in original packaging. Do not open the package before storage. Storage conditions in original packaging: storage temperature 25 °C ... +45 °C, relative humidity ≤75% annual mean, maximum 95%, dew precipitation is inadmissible. Avoid contamination of thermistors surface during storage, handling and processing.
Inrush current limiters B57236 ICLs S236 Mounting When NTC thermistors are encapsulated with sealing material or overmolded with plastic material, the precautions given in chapter “Mounting instructions”, “Sealing and potting” must be observed. Electrode must not be scratched before/during/after the mounting process. Contacts and housings used for assembly with thermistor have to be clean before mounting. During operation, the inrush current limiters surface temperature can be very high.
Inrush current limiters B57236 ICLs S236 Symbols and terms Symbol English German B B25/100 B value B value determined by resistance measurement at 25 °C and 100 °C B-Wert B-Wert, ermittelt durch Widerstandsmessungen bei 25 °C und 100 °C Ctest Cth Test capacitance Heat capacitance Prüfkapazität (elektrisch) Wärmekapazität I Imax Current Maximum current within stated temperature range NTC current Rated current Root-mean-square value of current Strom Maximalstrom im angegebenen Temperaturbereich
Inrush current limiters B57236 ICLs Symbol S236 English German Lower category temperature Untere Grenztemperatur (Kategorietemperatur) TR Tsurf Rated temperature Surface temperature Nenntemperatur Oberflächentemperatur V Vload VNTC VRMS Voltage Load voltage Voltage drop across an NTC thermistor Root-mean-square value of voltage Spannung Ladespannung Spannungsabfall am Heißleiter Effektivwert der Spannung α Temperature coefficient Temperaturkoeffizient ∆ Tolerance, change Toleranz, Änderu
Important notes The following applies to all products named in this publication: 1. Some parts of this publication contain statements about the suitability of our products for certain areas of application. These statements are based on our knowledge of typical requirements that are often placed on our products in the areas of application concerned.
