Resistors Resistors Ultra Low Profile Ultra Low Profile Power Resistors Power Resistors WDBR Series WDBR Series Ultra low profile thick-film on steel Ultra low profile thick-film on steel 500W to 7kW peak power 500W to 7kW peak power Single fixing heatsink mountable Single fixing heatsink mountable Ideal for dynamic braking, inrush limit and snubber circuits Ideal for dynamic braking , inrush limit and snubber circuits Choice of flying lead, push-on or solder terminations Choic e of flying lead, push- on or solder terminations Low inductance design Low inductance design High isolation, even aer fft ailsafe overload fusing High i solation, even after failsafe overload fusing RoHS compliant, non-flammable construction RoHS compliant, non-flammable construction All Pb-free parts comply with EU Directive 2011/65/EU (RoHS2) 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) ElectricElectricalal Da Datata WDBR1/2 WDBR1 WDBR2 WDBR3 WDBR5 WDBR7 WDBR1/2 WDBR1 WDBR2 WDBR3 WDBR5 WDBR7 12, 15, 20, 22, 25, 12, 15, 20, 22, 25, Resistance range ohms 12, 15, 20, 22, 25, 47, 50, 100, 150 Resistance range ohms 12, 15, 20, 22, 25, 47, 50, 100, 150 47, 50, 100 47, 50, 100 Resistance tolerance % 10 Resistance tolerance % 10 1 Pulse power rating 1 kW 0.5 1.5 2.0 3.5 5.0 7.0 Pulse power rating kW 0.5 1.5 2.0 3.5 5.0 7.0 2 Power rating on heatsink W 160 180 200 260 270 280 2 Power rating on heatsink W 160 180 200 260 270 280 3 Power rating on fan-cooled heatsink 3 W 300 700 780 900 1000 1490 Power rating on fan-cooled heatsink W 300 700 780 900 1000 1490 TCR ppm/C < +600 TCR ppm/C < +600 Maximum element temperature C 365 Maximum element temperature C 365 Ambient temperature range (heatsink) C -55 to +200 Ambient temperature range (heatsink) C -55 to +200 4 Dielectric withstand 4 V (dc/ac peak) 2500 Dielectric withstand V (dc/ac peak) 2500 Inductance (typical) H <3 <4 <5 <6 Inductance (typical) H <3 <4 <5 <6 Notes: Notes: 1. For details of pulse condition see Fig. 1 in Performance Data. 1. For details of pulse condition see Fig. 1 in Performance Data. 2. Mounted on a 0.53C/W heatsink with no forced air cooling, air temperature 25C. 2. Mounted on a 0.53C/W heatsink with no forced air cooling , air temperature 25C. 3. Mounted on a 0.53C/W heatsink with 5m/s forced air cooling, air temperature 25C. 3. Mounted on a 0.53C/W heatsink with 5m/s forced air cooling , air temperature 25C. 4. Based on 100% production test, duration 2s minimum 4. Based on 100% production test, duration 2s minimum Physical Data Physical Data Dimensions in mm, weight without terminations in g D c Dimensions in mm, weight without terminations in g Fixing hole is located cen- D c Fixing hole is located cen- a trally except on WDBR1/2 a trally except on WDBR1/2 L 0.1 W 0.1 t 0.1 D nom a nom b nom c nom Wt. nom L 0.1 W 0.1 t 0.1 D nom a nom b nom c nom Wt. nom where the dimension from where the dimension from the edge by the terminations WDBR1/2 31.9 28.1 2.2 7.5 3.1 4.3 6.5 the edge by the terminations WDBR1/2 31.9 28.1 2.2 7.5 3.1 4.3 6.5 to the mounting hole centre is W b to the mounting hole centre is b W 16.68mm. WDBR1 49.3 35.9 3.2 3.2 11.2 6.2 12.6 16.68mm. WDBR1 49.3 35.9 3.2 3.2 11.2 6.2 12.6 In addition to the central fixing WDBR2 61 40.6 0.9 4.7 13.0 5.8 17.1 In addition to the central fixing WDBR2 61 40.6 0.9 4.7 13.0 5.8 17.1 hole, WDBR7 has two corner L hole, WDBR7 has two corner L WDBR3 101.6 70 13.5 22.0 10.2 50.8 holes. These are present for WDBR3 101.6 70 13.5 22.0 10.2 50.8 holes. These are present for 5.3 manufacturing purposes only 5.3 Substratethickness =t manufacturing purposes only Substratethickness =t WDBR5 122 70 14.0 23.8 7.4 60.7 and should not be used as fix - WDBR5 122 70 14.0 23.8 7.4 60.7 and should not be used as fix - ing holes. ing holes. WDBR7 152.4 101.6 1.5 15.0 51.3 9.2 181.8 WDBR7 152.4 101.6 1.5 15.0 51.3 9.2 181.8 Construction Construction A high integrity dielectric layer is applied to a machined A high integrity dielectric layer is applied to a machined stainless steel substrate. Thick-film conductor and resistor stainless steel substrate. Thick-film conductor and resistor paerns artt e printed and fired, then protected with a high paernstt are printed and fired, then protected with a high temperature overglaze. The termination pads are tinned with temperature overglaze. The termination pads are tinned with solder and optional terminals or leads are soldered on. solder and optional terminals or leads are soldered on. General Note General Note BI Technologies IRC Welwyn BI Technologies IRC Welwyn TT Electronics reserves the right to make changes in product specification without notice or liability. 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. All information is subject to TT Electronics own data and is considered accurate at time of going to print. www.ttelectronics.com/resistors Ultra Low Profile Power Resistors WDBR Series Terminations The following termination options are available Option Code Nominal Dimensions (mm) PL WDBR Size 1, 2, 3, 5 & 7 1 Solder pad only I Pad Length, PL 7.5 9.0 PW Pad Width, PW 4.5 9.0 250mm Flying leads UL3134/5 L 3mm 40A, 600V TW TT WDBR Size 1, 2, 3, 5 & 7 Terminal Height, TH 7.5 12 TH Push-on connectors T Terminal Width, TW 2.8 6.3 Terminal Thickness, TT 0.8 0.8 Notes: 1. Two options exist for solder type. The standard is SnAg (96SC) which is Pb-free and the second (HT) is high temperature HMP alloy which is Pb-bearing. Both are RoHS compliant, but the second relies on the RoHS exemption for high temperature solders and is targeted at specialist high temperature applications. Thermal Performance Maximum Pulsed load at full pulse power rating 50,000 cycles (see Fig 1) 5 R% Mounted on a 0.53C/W heatsink with 5m/s forced air cooling, air temperature 25C. Derating at heatsink temperatures >160C See Fig. 2 Fig.2: TemperatureDerating Fig. 1: Duty CycleWaveform 120 1ms 100 Ppk 80 60 40 20 0 8s 1ms 050100 150200 250 2s Heatsink Temperature(C) 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 10.19 % of Rated Power