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RH25C, RH50C METAL CLAD, WIRE WOUND, CEMENT ENCASED RESISTORS

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RH25C and  RH50C are aluminum housed, metal clad cement encased resistors.  These models come in standard
RH25, 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.  RH25/50C
exhibit high stability at conventional power.

GENERAL SPECIFICATIONS

Model	Element Type	Rated Power		Resistance Range		Temperature coefficient [ppm/C] (-55C,25C,250C)				Resist- ance Tolerance	Min Ohmic Value
		With Heat Sink	In Free Air	Induc- tive	Non- Induc- tive	+-200 ppm/C	+-100 ppm/C	+-50 ppm/C	+-30 ppm/C
RH25 C	Wire Wound	20W	8W	.022Ω-25KΩ	0.1Ω- 10KΩ	0.022Ω-0.09Ω	0.1Ω- 0.976Ω	1Ω- 19.6Ω	20Ω-	+-0.1(B) +-0.25(C) +-0.5(D) +-1(F) +-2(G) +-5(J)	1Ω- 0.4Ω- 0.2Ω- 0.1Ω- 0.05Ω- 0.02Ω-
RH50 C	Wire wound	*30W	10W	.048Ω- 50KΩ	0.2Ω- 20KΩ	0.048Ω-0.09Ω	0.1Ω- 0.976Ω	1Ω- 19.6Ω	20Ω-
		*50W

*30W on heat sink size : AL 178 X 127 X 51 X 1t,  50W on heat sink size : AL 305 X 305X X 2t

CHARACTERISTICS                                                                                                          Values in [ ] mean change in W after test

Temperature Range	-55C to 250C
Insulation Resistance	10MΩ minimum  (at more than 100Ω)
Dielectric Strength	+-[0.2%+0.05Ω] AC2000V for 1 min, Max leakage current : 2mA
Short Time Overload	+-[0.5%+0.05Ω] Rated power X 5 for 5 secs
Thermal Shock	+-[0.5%+0.05Ω] Power rating 30 min, -55C 15 to 30 min
Moisture Resistance	+-[0.5%+0.05 Ω] 40C, 95% RH, DC100V case to terminal (500hrs.)
Load Life	+-[1%+0.05 Ω] Power rating 90 min on, 30 min off, 1000 hours

SURFACE TEMPERATURE INCREASE VERSUS POWER LOAD

DIMENSIONS

Model	Dimensions(mm)
	L1	L2	L3
RH 25 C	49.4	27.1	18.3
RHC 50 C	70.8	49.3	39.7

FREQUENCY CHARACTERISTIC CURVES

DERATING CURVE

RHC resistor have an operating temperature rage of -55C to 250C
Derating 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