USR UNR 4-3425 3825 3825H 4020 Precision Shunt Resistors • • • • • Resistances from 0.05Ohm to 500Ohms Power Rating to 50Watt Resistance Tolerances to ±0.01% TCR to ±1ppm/K Load Stability to 0.01% SPECIFICATIONS Type USR 43425 3825 USR 44020 Resistance Range UNR 43425 3825 UNR 44020 0.05 to 500 Ohms 0.05 to 400 Ohms other resistance values upon request / power rating depending on resistance value Power rating free air 70°C for 3825H with heatsink Thermal Resistance Rthj-c Tolerances from 0.05 Ohms from 10.0 Ohms from 50.0 Ohms 3W 5W 30 W 2.5 W 2.5 W 30 W 3W 5W 50 W 3.5 K/W 3.6 K/W 2.1 K/W 2.2 K/W 0.1% / 0.25% / 0.5% / 1% 0.05% / 0.1% / 0.25% / 0.5% / 1% 0.01% / 0.02% / 0.05% / 0.1% / 0.25% / 0.5% / 1% Stability 0.01% Shelf Life Stability 25ppm / ∆R after 1 year 50ppm / ∆R after 3 year Temperature Coefficient max. ±5ppm/K (-55 to 155°C) typ. ±3ppm/K (-55 to 125°C) upon request ±1ppm/K (0 to 60°C) Voltage Proof 750 VDC max. Current 15 A Thermal EMF < 0.1µV/K Operating Temperature Range -55 to 155°C Resistor Material Substrate 50 W NiCr-Foil Al2O3 Housing AlN Epoxy + Al-heatsink Connector Material Cu tinned Terminals 4 Max. Torque 1.0 Nm Notes Specially designed for applications with fast changing electrical load Ordering Information Part Number - Resistance - Contact - Tolerance - TCR USR 4-3825H 10Ohms D 0.5% 3ppm Powertron GmbH Potsdamer Strasse 18a D-14513 Teltow +49 (0)3328 3530-0 A Riedon Company www.powertron.de +49 (0)3328 3530-15 Page 127 rev. 03/2006A USR UNR 4-3425 3825 3825H 4020 Precision Shunt Resistors SPECIFICATIONS (continued) Temperature Coefficient 800 ∆R/R (ppm) 600 +5ppm/K -5ppm/K 400 200 Nominal Spread ±2.3ppm/K 0 -200 Nominal ∆R/R -400 Nominal Spread ±2.3ppm/K -600 -800 -50 0 -25 25 50 100 75 125 Temperature (°C) Power (% from nominal power) Derating Power Rating Notes - The U-Series Resistors must be attached to a suitable heatsink. The maximum internal resistor temperature is 155°C. To specify an appropriate heatsink use the following formula : 120 100 80 RqH = TMAX - ( P x RqR ) - TA P 60 40 20 0 25 50 85 100 115 130 145 155 Temperature of the backplate(°C) Where: RqH = Thermal Resistance of Heatsink ( K/W ) RqR = Thermal Resistance of Resistor ( K/W ) TMAX = Maximum Temperature of Resistor TA = Ambient Temperature of Heatsink ( °C ) P = Power Through Resistor ( W ) Dimensions USR 4-3425 / UNR 4-3425 Dimension mm tol. (±mm) inches tol. (±inches) A 50.00 2.0 1.97 0.079 B 34.00 0.3 1.34 0.012 C 25.00 0.2 0.98 0.008 D 10.00 0.2 0.39 0.008 E 5.00 0.1 0.20 0.004 F 17.80 0.2 0.70 0.008 G Ø3.50 0.1 Ø0.14 0.004 H Ø0.8 0.1 Ø0.031 0.004 I 27.50 0.2 1.08 0.008 J 17.50 0.2 0.69 0.008 K 2.00 0.1 0.08 0.004 L 5.50 0.1 0.22 0.004 M 3.00 0.2 0.12 0.008 Powertron GmbH Potsdamer Strasse 18a D-14513 Teltow +49 (0)3328 3530-0 A Riedon Company www.powertron.de +49 (0)3328 3530-15 Page 128 rev. 03/2006A USR UNR 4-3425 3825 3825H 4020 Precision Shunt Resistors SPECIFICATIONS (continued) USR 4-3825 / UNR 4-3825 Dimension mm tol. (±mm) inches tol. (±inches) A 49.00 2.0 1.93 0.079 B 38.00 0.3 1.50 0.012 C 24.00 0.2 0.94 0.008 D 4.00 0.1 0.16 0.004 E 34.00 0.3 1.34 0.012 F 17.50 0.2 0.69 0.008 G 1.5x45° 0.1 0.6x45° 0.004 H Ø0.8 0.1 Ø0.031 0.004 I 27.50 0.2 1.08 0.008 J 17.50 0.2 0.69 0.008 K Ø3.2 0.1 Ø0.126 0.004 L 2.00 0.1 0.08 0.004 M 5.50 0.1 0.22 0.004 N 15.00 0.2 0.59 0.008 O 3.00 0.2 0.12 0.008 Dimension mm tol. (±mm) inches tol. (±inches) A 49.00 2.0 1.93 0.079 B 38.00 0.3 1.50 0.012 C 24.00 0.2 0.94 0.008 D 4.00 0.1 0.16 0.004 E 34.00 0.3 1.34 0.012 F 17.50 0.2 0.69 0.008 G 1.5x45° 0.1 0.6x45° 0.004 H Ø0.8 0.1 Ø0.031 0.004 I 27.50 0.2 1.08 0.008 J 17.50 0.2 0.69 0.008 K Ø3.2 0.1 Ø0.126 0.004 L 2.00 0.1 0.08 0.004 M max.10.3 0.2 max.0.4 0.008 N 15.00 0.2 0.59 0.008 O 3.00 0.2 0.12 0.008 P 19.00 0.2 0.75 0.008 Dimension mm tol. (±mm) inches tol. (±inches) USR 4-3825H / UNR 4-3825H USR 4-4020 / UNR 4-4020 A 45.40 2.0 1.79 0.079 B 40.00 0.3 1.57 0.012 C 20.00 0.2 0.79 0.008 D 10.00 0.2 0.39 0.008 E 30.00 0.2 1.18 0.008 F 20.00 0.2 0.79 0.008 G Ø3.80 0.1 Ø0.15 0.004 H Ø0.8 0.1 Ø0.031 0.004 I 5.08 0.1 0.20 0.004 J 15.24 0.2 0.60 0.008 K 3.00 0.1 0.12 0.004 L 7.00 0.1 0.28 0.004 M 4.00 0.1 0.16 0.004 Powertron GmbH Potsdamer Strasse 18a D-14513 Teltow +49 (0)3328 3530-0 A Riedon Company www.powertron.de +49 (0)3328 3530-15 Page 129 rev. 03/2006A