metal clad resistors

RH25C and RH50C are aluminum housed, metal clad cement encased resistors. These models come in standardRH25, 50C or non-inductive RH25, 50 C N windings. The cement molding construction conforms to RoHS guidelines.Construction is completely welded. These models also mount on chassis to utilize heat sink cooling. RH25/50Cexhibit high stability at conventional power.GENERAL SPECIFICATIONSModel ElementType Rated Power ResistanceRange Temperature coefficient [ppm/C](-55C,25C,250C) Resist-anceTol. MinOhmicValue WithHeatSink InFreeAir Induc-tive Non-Induc-tive -15C,25C,105C Measuring Temp. -55, 25C, 250C +200 +-100 +-50 +-30 RH25 C WireWound 20W 8W .022?-25K? 0.1?-10K? +-200 0.022?-0.09? 0.1?-0.976? 1?-19.6? 20?- +-0.1(B)+-0.25(C)+-0.5(D)+-1(F)+-2(G)+-5(J) 1?-0.4?-0.2?-0.1?-0.05?-0.02?- RH50 C Wirewound 30,50W* 10W .048?-50K? 0.2?-20K? / 0.048?-0.09? 0.1?-0.976? 1?-19.6? 20?- FRH25 C ThickFilm 15W 5W / 2?-2M? 2?-2M? / / / / FRH50 C ThickFilm 25W 8W / 2?-2M? 2?-2M? / / / / *30W on heat sink size : AL 178 X 127 X 51 X 1t, 50W on heat sink size : AL 305 X 305X X 2tCHARACTERISTICS Values in [ ] mean change in W after testTemperature Range -55C to 250C Insulation Resistance 20M& minimum (at more than 100?) Dielectric Strength +-[0.2%+0.05?] AC2000V for 1 min, Max leakage current : 2mA Short Time Overload +-[0.5%+0.05?] Rated power X 5 for 5 secs Thermal Shock +-[0.5%+0.05&] Power rating 30 min, -55C 15 to 30 min Moisture Resistance +-[0.5%+0.05 &] 40C, 95% RH, DC100V case to terminal (500hrs.) Load Life +-[1%+0.05 &] Power rating 90 min on, 30 min off, 1000 hours SURFACE TEMPERATURE INCREASE VERSUS POWER LOADDIMENSIONSModel Dimensions(mm) Weight[g] L1 L2 L3 RH 25 C 49.4 27.1 18.3 29 RHC 50 C 70.8 49.3 39.7 16 FRH 25 C 49.4 27.1 18.3 29 FRH 50 C 70.8 49.3 39.7 16.5 FREQUENCY CHARACTERISTIC CURVESDERATING CURVERHC resistor have an operating temperature rage of -55C to 250CDerating is required for reduced chassis mounting area and for high ambient temperatures.The following curves apply to operation of unmounted resistors.Heat sink size [mm]:178 X 127 X 51 X 1t (RH 25 C)305 X 305 X 2 (RH 50 C)ORDERING PROCEDURE EXAMPLE