Resistors High Voltage High Voltage Welwyn Components Thick Film Resistors Thick Film Resistors VRW Series VRW Series VRW37 meets the requirements of BS / EN / IEC 60065 VRW37 meets requirements of BS / EN / IEC 60065 High working voltage to 10kV in compact High working voltage to 10kV in compact size size High ohmic range to 68M High ohmic range to 68M High pulse load capability High pulse load capability Robust flameproof coating material Robust flameproof coating material Surface mount ZI-form option RoHS compliant AllAll Pb-Pb-frfreeee partsparts ccomplyomply withwith EUEU DirDirectivectivee 2011/65/EU2011/65/EU amended amended b yb y(EU) (EU) 2015/863 2015/863 (R (RoHS3)oHS3) Electrical Data V WR 25 V WR 37 VRW68 Pow re ing ta 70 C aw tts 5 1.0 eR sist na ce r na eg (O mh s) K to 03 M K to 03 M 100K to 68M Limiting element ov ltage ov lts cd or ac p 10000 Is lo at oi n v lo tage ov lts T RC p mp / C eR sist na ce Toler na ce % 1 Standard Values E24 or E96 rmal Im ce C/ aw tt 70 Ambient et mp ure ar nge - 55 to + C Physical Data (Dimensions (mm) & Weight (g) Type L D f d PCB Min Wt. d Max Max min Nom mount bend nom centres radius VRW25 6.2 2.5 21 0.60.05 10.2 0.6 0.3 d D L f 9.0 3.7 19.6 0.80.05 12.7 1.2 0.5 VRW37 VRW68 15.5 5.0 27 0.80.05 20.3 1.2 1.15 Construction Terminations Resistive thick film material is applied to high-grade ceramic Material: Hot tin dipped copper wire rods. Tin-plated steel caps are force fitted and the Strength: The terminations meet the requirements termination wires are welded to the caps. The value is of IEC 68.2.21 obtained by a helical cut in the film and finally the resistor Solderability: The terminations meet the requirements body is protected by a cement coating. of IEC 115-1 Clause 4.17.3.2 Solvent Resistance Marking The body protection and marking are resistant to all normal 1% tolerance resistors are colour coded with 5 bands. 2% industrial cleaning solvents suitable for printed circuits. and 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 General Note BI Technologies IRC Welwyn TT Electronics reserves the right to make changes in product specification without notice or liability. Welwyn Components 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. All information is subject to Welwyns own data and is considered accurate at time of going to print. A subsidiary of www.ttelectronics.com/resistors TT electronics plc Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK TT Electronics plc 05.08 Telephone: +44 (0) 1670 822181 Facsimile: +44 (0) 1670 829465 Email: info welwyn-tt.com Website: www.welwyn-tt.com Issue C 07.06 06.18 70 C 551 tare 211 041 nadep ehT 5, 2, 002 007 0053 0061 kae 001 001 5.0 2.0 tarHigh Voltage High Voltage High Voltage High Voltage High Voltage Thick Film Resistors Thick Film Resistors TThick Film Rhick Filmesis Rteorsistors s Welwyn Components Welwyn Components VSTRQhiW SeriesP cSeriek Fsilm Resistors VSRQW SeriesP Series Welwyn Components VSVRRQW SeriesW SeriesP Series Welwyn Components VSRQW SeriesP Series Performance Data Performance Data Performance Data Performance Data Maximum Typical Maximum Typical Load at rated voltage (1000hrs at 70C) R% 1.5* 0.4 Maximum Typical Load at rated voltage (1000hrs at 70C) R% 1.5* 0.4 Maximum Typical Derating from rated power at 70 C zero at 155 C Load at rated voltage (1000hrs at 70C) R% 1.5* 0.4 Derating from rated power at 70 C zero at 155 C Load at rated voltage (1000hrs at 70C) R% 1.5* 0.4 Overload (10 x 5s at 6.25 x Pr not exceeding 2 x LEV or 10kV in air)Overload (10 x 5s at 6.25 x Pr not exceeding 2 x LEV) R% 12 0.15 Derating from rated power at 70 C zero at 155 C Overload (10 x 5s at 6.25 x Pr not exceeding 2 x LEV or 10kV in air)Overload (10 x 5s at 6.25 x Pr not exceeding 2 x LEV) R% 1 0.15 2 Derating from rated power at 70 C zero at 155 C Damp heat steady state (56 days, 40C, 90% RH) R% 1.5 0.1 Overload (10 x 5s at 6.25 x Pr not exceeding 2 x LEV or 10kV in air)Overload (10 x 5s at 6.25 x Pr not exceeding 2 x LEV) R% 12 0.15 Damp heat steady state (56 days, 40C, 90% RH) R% 1.5 0.1 Overload (10 x 5s at 6.25 x Pr not exceeding 2 x LEV or 10kV in air)Overload (10 x 5s at 6.25 x Pr not exceeding 2 x LEV) R% 1 0.15 2 Climatic sequence R% 1.5 0.2 Damp heat steady state (56 days, 40C, 90% RH) R% 1.5 0.1 Climatic sequence R% 1.5 0.2 Damp heat steady state (56 days, 40C, 90% RH) R% 1.5 0.1 Climatic category 55/155/56 Climatic sequence R% 1.5 0.2 Climatic category 55/155/56 Climatic sequence R% 1.5 0.2 Temperature rapid change R% 0.5 0.05 Climatic category 55/155/56 Temperature rapid change R% 0.5 0.05 Climatic category 55/155/56 Resistance to solder heat R% 0.5 0.05 Temperature rapid change R% 0.5 0.05 Resistance to solder heat R% 0.5 0.05 Temperature rapid change R% 0.5 0.05 Vibration R% 0.5 0.05 Resistance to solder heat R% 0.5 0.05 Vibration R% 0.5 0.05 Resistance to solder heat R% 0.5 0.05 Voltage Proof volts 700 min Vibration R% 0.5 0.05 Voltage Proof volts 700 min Vibration R% 0.5 0.05 * 2% for ohmic values above 24M Voltage Proof volts 700 min * 2% for ohmic values above 24M Voltage Proof volts 700 min * 2% for ohmic values above 24M Pulse Performace Pulse Performace * 2% for ohmic values above 24M Pulse Performance Pulse Performance Pulse Performace 100 Pulse Performace Pulse Performance 100 Pulse Performance 100 100 VRW25 VRW25 10 VRW37 VRW37 10 VRW25 VRW25 VRW68 VVRRWW3678 10 VRW37 10 VRW68 VRW68 1 1 0.1 1 10 100 0.1 1 10 100 1 1 0.1 1 10 100 Value (megohms) Value (megohms) 0.1 1 10 100 Value (megohms) Value (megohms) Maximum peak voltage in accordance with IEC 60065 chapter 14.1 Maximum peak voltage in accordance with IEC 60065 chapter 14.1 50 discharges from a 1nF capacitor charged to V max. 12 discharges/minute. M50a xidiscmuhargem peaks fr omvoltage a 1nF in caaccpaocirdtoran cecha witrgehd tIECo V 6 ma00x.65 1 c2h adiscptehra 1rg4es/.1minute. Maximum peak voltage in accordance with IEC 60065 chapter 14.1 50 discharges from a 1nF capacitor charged to V max. 12 discharges/minute. 50 discharges from a 1nF capacitor charged to V max. 12 discharges/minute. Application Notes Application Notes Application Notes 1. Due to operating temperature limits imposed by some PCB materials, derating may be necessary. An 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 1.es tDuimate toe of opera the tintemperag temtperatuure risree tliom bites expecimposetedd bayt tsohem cee PCnteBr matof therie abols,dy de cranati ngbe macalcy ublaet needc uesissangry th. Aen 1. Due to operating temperature limits imposed by some PCB materials, derating may be necessary. An thermal impedance figures given under Electrical Data. etherstimmatale impedanof the temperace figurteusr egiv risene tuon bdee rexpec Electtedrica la Dt atathe. center of the body can be calculated using the 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. 2. VRW resistors can be supplied with radial, goalpost or lancet pre-formed leads. The VRW37 is also thermal impedance figures given under Electrical Data. 2. VRW resistors can be supplied with radial, goalpost or lancet pre-formed leads. The VRW37 is also available in ZI-form SMD format packed in blister tape - see