POWER - NIKKOHM
RoHS
20W, 50W Wire Wound Resistors
RH25C, RH25CN, RH50C, RH50CN
Features and Applications
Inductive (RH25C, RH50C), non-inductive (RH25CN, RH50CN) aluminum clad housed wire-wound resistors.
Cement molded resistors construction gives complete environmental protection and 250 deg C high
temperature operation.
Complete welding terminal construction.
Braking resistor and dumping resistor of the motor control, rush current protection, gate resistor, snubber
resistor.
Dimensional Specifications (mm)
2-3.2X4 slot
2-φ2.0
C
B
A
3.7+/-0.2
Specifications
Rated Watt Rated Watt
Heat Sink
Free Air
（Ｗ）
（Ｗ）
RH25C
20
8
RH25CN
20
8
RH50C
30, 50(1)
10
RH50CN
30, 50(1)
10
(1) Please see note (1) in next page.
Type
Resistance
（ohm）
0.022-25K
0.1-10K
0.048-50K
0.2-20K
200ppm
0.022-0.09
-
0.048-0.09
-
TC Lower Limit
(±ppm/K)
100ppm
50ppm
0.1-0.976
1-19.6
0.1-0.976
1-19.6
0.1-0.976
1-19.6
0.2-0.976
1-19.6
30ppm
20-25K
20-10K
20-50K
20-20K
Ｔ½½½½½½½½
（%）
±0.1(B), ±0.2(C),
±0.5(D), ±1.0(F)
±2.0(G), ±5.0(J)
Characteristics
Short time overload
Heat shock
Dielectric strength
Insulation resistance
Load life
Operating temp. range
Storage temp. range
Specifications
±0.5%
±0.5%
±0.2%
10Gohm
±1.0%
-55 to +250 deg C
-55 to +250 deg C
Test Condition
2000VAC, 60seconds, 2mA
Ordering Information
RH50C 51ohmB
RH25CN100ohmF
Type
RH50C
RH25CN
Resistance
51ohm
100ohm
Tolerance
0.1%(B)
1.0%(F)
Remarks
Inductive
Non-inductive
G
H
Symbol
A
B
C
D
E
F
G
H
Weight
RH25C, RH25CN
49.4±0.2
27.1+0.15-0.10
18.3±0.2
29.6±0.2
20.6±0.2
15.6±0.2
16±0.2
2.2±0.2
16.5gr
RH50C, RH50NC
70.6±0.2
49.3+0.15-0.10
39.7±0.2
29.6±0.2
20.6±0.2
15.6±0.2
16±0.2
2.2±0.2
35gr
2
D
E
F
POWER - NIKKOHM
20W, 50W Wire Wound Resistors
RoHS
RH25C, RH25CN, RH50C, RH50CN
Temperature Rise, RH25C
Temperature Rise (deg C), RH25C
120
100
80
60
40
20
0
0
5
10
15
20
25
30
35
Applied Power (W)
With heat sink
Free Air
Temperature Rise, RH50C
Temperature Rise (deg C)
ＲＨ
50C
120
100
80
60
40
20
0
0
10
20
30
40
50
60
70
Applied Power (W)
With heat sink
Free Air
Derating. RH25C
Applied % Power
120
100
80
60
40
20
0
0
25
50
75 100 125 150 175 200 225 250 275 300
Ambient Temperature (deg C)
Derating.RH50C
Applied % Power
120
100
RH25C on heat sink.
RH25C free air
80
60
40
20
0
0
25
50
RH50C on heat sink.
RH50C free air
75 100 125 150 175 200 225 250 275 300
Ambient Temperature (deg C)
Frequency Characteristics. RH50C and RH50CN
Impedance(ohm)
1K
RH50C
100
Note:
(1) 30W rating power of RH50C is on heat sink
(178x127x51x1mm), 50W power of RH50C
is on heat sink (305x305x2mm)
(2) RH20 and RH50 were discontinued by
reason of increasing high temperature
performance, and replace to RH25C and
RH50C.
RH50CN
10
100K
1M
10M
100M
Frequency(Hz)
20091020
