VRW37-680KJI

High Voltage Thick Film Resistors VRW Series VRW37 meets the requirements of BS / EN / IEC 60065 High working voltage to 3.5kV in compact size High ohmic range to 30M High pulse load capability Robust flameproof coating material RoHS compliant Electrical Data VRW37 VRW25 0.5 Power rating at 70C watts 0.25 Resistance range ohms 100K to 30M 100K to 10M 3500 Limiting element voltage volts dc or ac peak 1600 Isolation voltage volts 700 TCR ppm/C 200 Resistance Tolerance % 1, 2, 5 Standard Values E24 and E96 preferred 112 Thermal Impedance C/watt 140 Ambient temperature range C -55 to +155 Physical Data Dimensions (mm) & Weight (g) PCB Min Wt. Type L max D max f min d nom mount bend nom centres radius VRW25 6.2 2.5 21 0.6 10.2 0.6 0.3 VRW37 9.0 3.7 19.6 0.8 12.7 1.2 0.5 Terminations Construction Resistive thick film material is applied to high-grade ceramic Material: Hot tin dipped copper wire Strength: The terminations meet the requirements of IEC rods. Tin-plated steel caps are force fitted and the termination 68.2.21 wires are welded to the caps. The value is obtained by a helical cut in the film and finally the resistor body is protected Solderability: The terminations meet the requirements of IEC 115-1 Clause 4.17.3.2 by a cement coating applied so that the terminations remain completely clear. Solvent Resistance Marking The body protection and marking are resistant to all normal industrial 1% tolerance resistors are colour coded with 5 bands. 2% and cleaning solvents suitable for printed circuits. 5% tolerance have 4 bands. IEC62 colours are used. Flammability The resistor coating will not burn under any condition of applied temperature or power overload. General Note Welwyn Components reserves the right to make changes in product specification without notice or liability. All information is subject to Welwyns own test data and is considered accurate at time of print. A subsidiary of TT electronics plc Welwyn Components Limited Issue B 05.06 Welwyn Electronics Park, Bedlington, Northumberland, NE22 7AA, England. Tel: 01670 822181 Fax: 01670 829465 Web: www.welwyn-tt.com Performance Data Maximum Typical Load at rated voltage (1000hrs at 70C) 1.5 0.4 R% Derating from rated power at 70C zero at 155C Overload* 1 0.15 R% Damp heat steady state (56 days, 40C, 90% RH) 1.5 0.1 R% Climatic sequence 1.5 0.2 R% Climatic category 55/155/56 Temperature rapid change 0.5 0.05 R% Resistance to solder heat 0.5 0.05 R% Vibration 0.5 0.05 R% Voltage Proof volts 700 min * The overload test is 10 pulses of 5 seconds, 45 Pulse Performance seconds between each pulse. The power applied is 6.25 x that of the rated power, but not exceeding 100 2 x the limiting element voltage. VRW25 10 VRW37 1 0.01 0.1 1 10 100 Megaohms Maximum peak voltage in accordance with IEC 60065 chapter 14.1 50 discharges from a 1nF capacitor charged to V max. 12 discharges/minute. Application Notes 1. Due to operating temperature limits imposed by some PCB materials, derating may be necessary. An estimate of the temperature rise to be expected at the center of the body can be calculated using the thermal impedance figures given under Electrical Data. Figure 1 2. VRW resistors can be supplied with radial, goalpost or lancet pre-formed leads. The VRW37 is also available in an SMD format with Z formed leads and packed in blister tape. Consult Factory for details. 5mm Packaging Our standard packaging for VRW is taped and boxed. The critical f1 f2 6 6 dimensions are shown in Figure 1. The component wires will not 52mm protrude beyond the outside edge of the tapes. Alternative mm mm Body location f1-f2 < 1.4mm packaging is available by request. Pre-formed resistors are supplied loose packed in plastic bags or boxes. Ordering Procedure Example: VRW25 at 1.2 megohms and 5% tolerance in ammo pack box of 5000 pieces - V R W 2 5 1 M 2 J I Type Value (use IEC62 code) Tolerance (use IEC62 code) F 1% G 2% J 5% Packing VRW25 5000/box Standard I Ammo VRW37 2500/box General Note Welwyn Components reserves the right to make changes in product specification without notice or liability. All information is subject to Welwyns own test data and is considered accurate at time of print. A subsidiary of TT electronics plc Welwyn Components Limited Issue B 05.06 Welwyn Electronics Park, Bedlington, Northumberland, NE22 7AA, England. Tel: 01670 822181 Fax: 01670 829465 Web: www.welwyn-tt.com Vmax (kV)