RH, NH
Vishay Dale
www.vishay.com
122 Document Number 30201
Revision 18-Feb-03
For technical questions, contact ww2bresistors@vishay.com
FEATURES
• Molded construction for total environmental protection
• Complete welded construction
• Meets applicable requirements of MIL-PRF-18546
• Available in non-inductive styles (type NH) with Aryton-
Perry winding for lowest reactive components
• Mounts on chassis to utilize heat-sink effect
• Excellent stability in operation
Wirewound Resistors, Military, MIL-PRF-18546 Qualified,
Type RE, Aluminum Housed, Chassis Mount
NOTE: Figures in parentheses on RH-5 and RH-10 indicate wattage printed on parts, new construction allows these resistors to be rated at
higher wattage but will only be printed with the higher wattage on customer request.
ORDERING INFORMATION
RH-50 10Ω1.0%
MODEL RESISTANCE TOLERANCE
Ω± %
RESISTANCE RANGE
MIL. RANGE SHOWN IN BOLD FACE
STANDARD ELECTRICAL SPECIFICATIONS
MODEL
RH-5
NH-5
RH-10
NH-10
RH-25
NH-25
RH-50
NH-50
RH-100
NH-100
RH-250
NH-250
MIL-PRF-
18546
TYPE
—
RE60G
—
RE60N
—
RE65G
—
RE65N
—
RE70G
—
RE70N
—
RE75G
—
RE75N
—
RE77G
—
RE77N
—
RE80G
—
RE80N
DALE
7.5 (5)
7.5 (5)
12.5 (10)
12.5 (10)
25
25
50
50
100
100
250
250
MILITARY
5
5
10
10
20
20
30
30
75
75
120
120
± 0.05%, ± 0.1%
0.5 - 6.75k
—
0.5 - 2.32k
—
0.5 - 12.7k
—
0.5 - 4.45k
—
0.5 - 25.7k
—
0.5 - 9.09k
—
0.5 - 73.4k
—
0.5 - 26k
—
0.5 - 90k
—
0.5 - 37.5k
—
0.5 - 116k
—
0.5 - 48.5k
—
± 0.25%
0.1 - 8.6k
—
0.1 - 3.27k
—
0.1 - 16.69k
—
0.1 - 5.54k
—
0.1 - 32.99k
—
0.1 - 12.8k
—
0.1 - 96k
—
0.1 - 36.7k
—
0.1 - 90k
—
0.1 - 37.5k
—
0.1 - 116k
—
0.1 - 48.5k
—
± 0.5%
0.05 - 8.6k
—
0.05 - 3.27k
—
0.05 - 16.69k
—
0.05 - 5.54k
—
0.05 - 32.99k
—
0.05 - 12.8k
—
0.05 - 96k
—
0.05 - 36.7k
—
0.05 - 90k
—
0.05 - 37.5k
—
0.05 - 116k
—
0.05 - 48.5k
—
±
1%,
±
3%,
±
5%
0.02 - 24.5k
0.10 - 3.32k
0.05 - 12.75k
1.0 - 1.65k
0.01 - 47.1k
0.10 - 5.62k
0.05 - 23.5k
1.0 - 2.8k
0.01 - 95.2k
0.10 - 12.1k
0.05 - 47.6k
1.0 - 6.04k
0.01 - 273k
0 .10 - 39.2k
0.05 - 136k
1.0 - 19.6k
0.05 - 90k
0.05 - 29.4k
0.05 - 37.5k
1.0 - 14.7k
0.05 - 116k
0.10 - 35.7k
0.05 - 48.5k
1.0 - 17.4k
WEIGHT
(Typical)
g
3
3.3
6
8.8
13
16.5
28
35
350
385
630
690
POWER RATING
P25°C
W Ω
www.vishay.com
123
RH, NH
Vishay Dale
Document Number 30201
Revision 18-Feb-03 For technical questions, contact ww2bresistors@vishay.com
DIMENSIONS
Wirewound Resistors, Military, MIL-PRF-18546 Qualified,
Type RE, Aluminum Housed, Chassis Mount
MODEL
DIMENSIONS in inches [millimeters]
ABC DE FGHJKLMNP
RH-5 0.444 0.490 0.600 1.125 0.334 0.646 0.320 0.065 0.133 0.078 0.093 0.078 0.050 0.266
NH-5 ± 0.005 ± 0.005 ± 0.031 ± 0.062 ± 0.015 ± 0.015 ± 0.015 ± 0.010 ± 0.010 ± 0.010 ± 0.005 ± 0.015 ± 0.005 ± 0.062
[11.28 [12.45 [15.24 [28.58 [8.48 [16.41 [8.13 [1.65 [3.38 [1.98 [2.36 [1.98 [1.27 [6.76
± 0.127] ± 0.127] ± 0.787] ± 1.57] ± 0.381] ± .381] ± 0.381] ± 0.254] ± 0.254] ± 0.254] ± 0.127] ± .381] ± 0.127] ± 1.57]
RH-10 0.562 0.625 0.750 1.375 0.420 0.800 0.390 0.075 0.165 0.093 0.094 0.102 0.085 0.312
NH-10 ± 0.005 ± 0.005 ± 0.031 ± 0.062 ± 0.015 ± 0.015 ± 0.015 ± 0.010 ± 0.010 ± 0.010 ± 0.005 ± 0.015 ± 0.005 ± 0.062
[14.27 [15.88 [19.05 [34.93 [10.67 [20.32 [9.91 [1.91 [4.19 [2.36 [2.39 [2.59 [2.16 [7.92
± 0.127] ± 0.127] ± 0.787] ± 1.57] ± 0.381] ± 0.381] ± 0.381] ± 0.254] ± 0.254] ± 0.254] ± 0.127] ± 0.381] ± 0.127] ± 1.57]
RH-25 0.719 0.781 1.062 1.938 0.550 1.080 0.546 0.075 0.231 0.172 0.125 0.115 0.085 0.438
NH-25 ± 0.005 ± 0.005 ± 0.031 ± 0.062 ± 0.015 ± 0.015 ± 0.015 ± 0.010 ± 0.010 ± 0.010 ± 0.005 ± 0.015 ± 0.005 ± 0.062
[18.26 [19.84 [26.97 [49.23 [13.97 [27.43 [13.87 [1.91 [5.87 [4.37 [3.18 [2.92 [2.16 [11.13
± 0.127] ± 0.127] ± 0.787] ± 1.57] ± .381] ± 0.381] ± 0.381] ± 0.254] ± 0.254] ± 0.254] ± 0.127] ± 0.381] ± 0.127] ± 1.57]
RH-50 1.562 0.844 1.968 2.781 0.630 1.140 0.610 0.088 0.260 0.196 0.125 0.107 0.085 0.438
NH-50 ± 0.005 ± 0.005 ± 0.031 ± 0.062 ± 0.015 ± 0.015 ± 0.015 ± 0.010 ± 0.010 ± 0.010 ± 0.005 ± 0.015 ± 0.005 ± 0.062
[39.67 [21.44 [49.99 [70.64 [16.00 [28.96 [15.49 [2.24 [6.60 [4.98 [3.18 [2.72 [2.16 [11.13
± 0.127] ± 0.127] ± 0.787] ± 1.57] ± 0.381] ± 0.381] ± 0.381] ± 0.254] ± 0.254] ± 0.254] ± 0.127] ± 0.381] ± 0.127] ± 1.57]
RH-250, NH-250
RH-100, NH-100
2.25
±
0.010
[57.15
±
0.254]
0.989
±
0.031
[25.12
±
0.787]
2.812
±
0.031
[71.42
±
0.787]
3.50
±
0.031
[88.90
±
0 .787]
Nickel Plated
Brass Nut
Stainless Steel Stud
1.125
±
0.031
[28.58
±
0.787]
0.188
±
0.010
[4.78
±
0.254]
Dia. Typ.
12 - 24
UNC-2A
Thd. Typ. 2.75
±
0.010
[69.85
±
0.254]
.375
±
0.031
[9.52
±
0.787]
5.478
±
0.093
[139.14
±
2.36]
1.75 ±0.031
[44.45 ±0.787]
2.188 ±0.031
[55.58 ±0.787]
2.125 ±0.031
[53.98 ±0.787]
0.250 ±0.031
[6.35 ±0.787]
Typ.
4.50
±
0.031
[114.30
±
0.787]
2.50
±
0.010
[63.50
±
0.254]
Nickel Plated
Brass Nut
Stainless Steel Stud
7.0
±
.093 [177.80
±
2.36]
0.875
±
0.010
[22.23
±
.254]
3.0
±
0.010
[76.20
±
.254]
3.875
±
0.010
[98.42
±
0.254]
0.770 ±0.015
[19.56 ±0.381]
0.188 ±0.031
[4.78 ±0.787]
Typ.
1.812 ±0.031
[46.02 ±0.787]
.312
±
0.031
[7.92
±
0.787]
1.25
±
0.062
[31.75
±
1.575]
1.25
±
0.062
[31.75
±
1.575]
1/4 - 20
UNC-2A Thd.Typ.
0.188
±
0.010
[4.78
±
0.254]
Dia. Typ.
0.955 ±0.015
[24.26 ±.381]
RH-5, -10, -25, -50
NH-5, -10, -25, -50
P
D
C
A
L
M
N
J
F
E
H
G
K
B
3.0
±
.031
[76.20
±
0.787]
RH, NH
Vishay Dale
www.vishay.com
124 Document Number 30201
Revision 18-Feb-03
For technical questions, contact ww2bresistors@vishay.com
Wirewound Resistors, Military, MIL-PRF-18546 Qualified,
Type RE, Aluminum Housed, Chassis Mount
POWER RATING
Vishay RH resistor wattage ratings are based on mounting to the following heat sink:
RH-5 and RH-10: 4" x 6" x 2" x 0.040" thick aluminum chassis (129 sq. in. surface area)
RH-25: 5" x 7" x 2" x 0.040" thick aluminum chassis (167 sq. in. surface area)
RH-50: 12" x 12" x 0.059" thick aluminum panel (291 sq. in. surface area)
RH-100 and RH-250: 12" x 12" x 0.125" thick aluminum panel (294 sq. in. surface area)
AMBIENT TEMPERATURE DERATING
Derating is required for ambient temperatures above 25°C, see the following graph.
Curves A, B, C apply to operation of unmounted resistors. Curve D applies to all types when mounted to specified heat sink.
A = RH-5 and RH-10 size resistor, unmounted
B = RH-25 size resistor, unmounted
C = RH-50, RH-100 and RH-250 size resistor, unmounted
D = All types mounted to recommended aluminum heat sink
RATED POWER IN %
Derating
REDUCED HEAT SINK DERATING:
Derating is also required when recommended heat
sink area is reduced.
A = RH-5 and RH-10 size resistor
B = RH-25 size resistor
C = RH-50, RH-100 and RH-250 size resistor
100
90
80
70
60
50
40
30
20
10
00 20 40 60 80 100
% OF RECOMMENDED HEAT SINK AREA
RATED POWER IN %
Heat Sink Derating
A
C
B
-55 -50 0 50 150 250
AMBIENT TEMPERATURE IN °C
25
120
A
C
D
B
0
20
40
60
80
100
PARAMETER UNIT RH RESISTOR CHARACTERISTICS
Temperature Coefficient ppm/°C± 100 for 0.1Ω to 0.99Ω, ± 50 for 1Ω to 9.9Ω, ± 20 for 10Ω and above
Dielectric Withstanding Voltage VAC 1000 for RH-5, RH-10 and RH-25, 2000 for RH-50, 4500 for RH-100 and RH-250
Short Time Overload - 5 x rated power for 5 seconds
Maximum Working Voltage V (P X R)1/2
Insulation Resistance Ω10,000 Megohm minimum dry, 1000 Megohm minimum after moisture test
Terminal Strength lb 5 minimum for RH-5 and RH-10, 10 minimum for all others
Solderability - MIL-PRF-18546 Type - Meets requirements of ANSI J-STD-002
OperatingTemperature Range °C - 55/+ 250
TECHNICAL SPECIFICATIONS
www.vishay.com
125
RH, NH
Vishay Dale
Document Number 30201
Revision 18-Feb-03 For technical questions, contact ww2bresistors@vishay.com
Wirewound Resistors, Military, MIL-PRF-18546 Qualified,
Type RE, Aluminum Housed, Chassis Mount
MATERIAL SPECIFICATIONS
Element: Copper-nickel alloy or nickel-chrome alloy,
depending on resistance value
Core: Ceramic, steatite or alumina, depending on physical
size
Encapsulant: Silicone molded construction
Housing: Aluminum with hard anodic coating
End Caps: Stainless steel
Standard Terminals: Tinned Copperweld® on RH-5 through
RH-50 size, threaded stainless steel terminals on RH-100
and RH-250
Part Marking: DALE, Model, Wattage, Value, Tolerance,
Date Code
NH NON-INDUCTIVE
Models of equivalent physical and electrical specifications are
available with non-inductive (Aryton-Perry) winding. They are
identified by substituting the letter N for R in the model
number (NH-5, for example).
SPECIAL MODIFICATIONS
A number of special modifications to the aluminum housed
resistor style are available upon request. Special
modifications include:
• Terminal configurations and materials
• Resistance values and tolerances
• Low resistance temperature coefficient (RTC)
• Housing configuration
• Threaded mounting holes
• Preconditioning and other additional testing
APPLICABLE MIL SPECIFICATIONS
MIL-PRF-18546 is the military specification covering
aluminum housed, chassis mount, power resistors. VISHAY
RH and NH resistors are listed as qualified on the
MIL-PRF-18546 QPL.
PERFORMANCE
TEST CONDITIONS OF TEST TEST LIMITS
Thermal Shock Rated power applied until thermally stable, then a minimum of 15 minutes at - 55°C± (0.5% + 0.05Ω) ∆R
Short Time Overload 5 x rated power for 5 seconds ± (0.5% + 0.05Ω) ∆R
1000Vrms for RH-5, RH-10 and RH-25; 2000Vrms for RH-50
4500Vrms for RH-100 and RH-250; duration one minute
Temperature 250°C for 2 hours ± (0.5% + 0.05Ω) ∆R
Moisture Resistance MIL-STD-202 Method 106, 7b not applicable ± (1.0% + 0.05Ω) ∆R
Shock, Specified Pulse MIL-STD-202 Method 213, 100g's for 6 miliseconds, 10 shocks ± (0.2% + 0.05Ω) ∆R
Vibration, High Frequency Frequency varied 10 to 2000Hz, 20g peak, 2 directions 6 hours each ± (0.2% + 0.05Ω) ∆R
Load Life 1000 hours at rated power, + 25°C, 1.5 hours “ON”, 0.5 hours “OFF” ± (1.0% + 0.05Ω) ∆R
30 second, 5 pound pull test for RH-5 and RH-10, 10 pound pull test for other
sizes, torque test - 24 pound inch for RH-100 and 32 pound inch for RH-250
Dielectric Withstanding Voltage ± (0.2% + 0.05Ω) ∆R
Terminal Strength ± (0.2% + 0.05Ω) ∆R
