Resistors Wirewound High Surge Resistors WHS Series Enhanced surge & pulse energy capacity UL94-V0 flameproof protection Radial taped form available Surface mount ZI-form option Non inductive type available All Pb-All Pb-frfreeee parts c parts comply omply with EU Dirwith EU Directivective e 2011/65/EU amended b2011/65/EU amended by y (EU) 2015/863 (R(EU) 2015/863 (RoHS3)oHS3) Electrical Data WHS2 / WHSP2R WHS3 WHS5 WHS7 WHS10 WHS10N* Power rating at 25C watts 2 3 5 7 10 5s overload rating at 25C watts 10 15 25 35 50 Short pulse performance See Pulse Performance graphs Resistance range ohms 1R0-330R 2R2-330R 5R6-100R TCR ppm/C 200 Isolation Voltage volts 250 350 500 700 1000 Resistance Tolerance % <20R: 5 20R: 1, 2, 5 5% Standard Values E24 preferred Thermal Impedance C/watt 110 82 54 35 25 Ambient temperature range C -55 to +155 No Limiting Element Voltage applies to this series the Rated Voltage is (P.R). *Non inductive (Ayrton Perry) winding Physical Data Dimensions (mm) & Weight (g) PCB Min d Type L max D max f min d max mount bend Wt. nom centres radius WHS2 9.0 3.6 19.80 12.50 0.50 D WHS3 14.5 5.2 24.55 20.00 1.10 0.81 1.2 L f WHS5 16.5 7.0 23.55 22.00 1.75 WHS7 25.0 8.8 28.30 31.00 4.40 WHS10 10.5 8.80 51.0 26.00 1.01 56.00 1.5 WHS10N 11.0 10.50 Construction A high purity ceramic substrate is assembled with interference fit end caps to which are welded the terminations. The resistive element is wound on the substrate and welded to the caps. Flameproof silicone cement coating is applied prior to marking with indelible ink. The components are then leadformed if required and packed. General Note BI Technologies IRC Welwyn TT Electronics reserves the right to make changes in product specification without notice or liability. All information is subject to TT Electronics own data and is considered accurate at time of going to print. www.ttelectronics.com/resistors TT Electronics plc 11.20Wirewound High Surge Resistors WHS Series Terminations Material: Hot tin dipped copper wire Strength: The terminations meet the requirements of IEC 68.2.21 Solderability: The terminations meet the requirements of IEC 115-1 Clause 4.17.3.2 Marking WHS2, WHSP2R and WHS3 resistors are marked with four colour bands in conformance with IEC62. The larger sizes are legend marked with type reference, resistance value and tolerance. Solvent Resistance The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits. Flammability The resistor coating will not burn or emit incandescent particles under any condition of applied temperature or power overload. Performance Data Maximum Typical Load at rated power: 1000hrs 25C R% 5 +0.001 3 Dry heat: 1000hrs 200C R% 5 +0.001 3 Short term overload R% 5 +0.001 1 Derating from rated power 25C Zero at 280C (See Thermal Performance graph). Climatic R% 5 +0.001 2 Climatic category 55/200/56 TRC & Vibration R% 5 +0.001 1 Robustness & solder heat R% 5 +0.001 1 Long term damp heat (56 days) R% 5 +0.001 1 Pulse Performance Surge / Pulse Energy Capacity (single or low repetition rate, R < 5%) 1000 WHS10N 100 WHS10 WHS7 WHS5 10 WHS3 WHS2 / WHSP2R 1 1 10 100 1000 Value (ohms) General Note BI Technologies IRC Welwyn TT Electronics reserves the right to make changes in product specification without notice or liability. All information is subject to TT Electronics own data and is considered accurate at time of going to print. www.ttelectronics.com/resistors TT Electronics plc 11.20 Energy (joules)