WHS7-1RJT07 TT Electronics

Wirewound High Surge Resistors WHS Series Enhanced surge & pulse energy capacity UL94-V0 flameproof protection Radial taped form available Surface mount Z-form available RoHS compliant with Pb-free terminations Electrical Data WHS2 WHS3 WHS5 WHS7 Power rating at 25C watts 2 3 5 7 5s overload rating at 25C watts 10 15 25 35 Short pulse performance See Pulse Performance graphs Resistance range ohms 1R0-330R TCR ppm/C 200 Isolation Voltage volts 250 350 500 700 Resistance Tolerance % <20R: 5 20R: 1, 2, 5 Standard Values E12 preferred Thermal Impedance C/watt 110 82 54 35 Ambient temperature range C -55 to +155 No Limiting Element Voltage applies to this series the Rated Voltage is (P.R). Physical Data Dimensions (mm) & Weight (g) PCB Min d Type L max D max f min d nom mount bend Wt. nom centres radius WHS2 9.0 3.6 19.80 12.70 0.50 D WHS3 14.5 5.2 24.55 20.30 1.10 L f 0.8 1.2 WHS5 16.5 7.0 23.55 22.86 1.75 WHS7 25.0 8.8 28.30 31.40 4.40 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 priorto marking with indelible ink. The components are then leadformed if required and packed. General Note 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.bitechnologies.com www.irctt.com www.welwyn-tt.com TT electronics plc 08. 12Wirewound 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, and WHS3 resistors are marked with four colour bands in conformance with IEC62. WHS5 and WHS7 resistors 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%) 100 WHS7 WHS5 10 WHS3 WHS2 1 1 10 100 1000 Value (ohms) General Note 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.bitechnologies.com www.irctt.com www.welwyn-tt.com TT electronics plc 08. 12 Energy (joules)