ESS, ESW, ESN, EGS, EGW, EGN
Wirewound Resistors, Military/Established Reliability
MIL-PRF-39007 Qualified, Type RWR, R Level
Vishay Dale
DIMENSIONS
MIL-PRF-39007
DIMENSIONS - in inches [millimeters]
1.50 [38.10]*
Min.
A
MODEL
RWR81
A
B
C
0.250 ± 0.031
[6.35 ± 0.787]
.085 ± 0.020
[2.16 ± 0.508]
0.020 ± 0.0015
[0.508 ± 0.038]
RWR82
RWR80
RWR71
RWR89
RWR74
RWR84
RWR78
0.312 ± 0.016
[7.92 ± 0.406]
0.406 ± 0.031
[10.31 ± 0.787]
0.812 ± 0.062
[20.62 ± 1.58]
0.560 ± 0.062
[14.22 ± 1.58]
0.875 ± 0.062
[22.23 ± 1.58]
0.875 ± 0.062
[22.23 ± 1.58]
1.780 ± 0.062
[45.21 ± 1.58]
0.078 + 0.016 - 0.031 0.020 ± 0.0015
[1.98 + 0.406 - 0.787] [0.508 ± 0.038]
C
B
0.094 ± 0.031
[2.39 ± 0.787]
0.020 ± 0.0015
[0.508 ± 0.038]
*On some standard reel pack methods, the leads may be
trimmed to a shorter length than shown.
0.187 ± 0.031
[4.75 ± 0.787]
0.032 ± 0.002
[0.813 ± 0.051]
MATERIAL SPECIFICATIONS
Element: Copper-nickel alloy or nickel-chrome alloy,
depending on resistance value
Core: Ceramic, Beryllium oxide, steatite or alumina,
depending on power requirement
Coating: Special high temperature silicone
Terminal and Winding: The terminal and the winding
are identified by a letter symbol in the military type
designation. Military Symbol:
0.187 ± 0.031
[4.75 ± 0.787]
0.032 ± 0.002
[0.813 ± 0.051]
0.312 ± 0.031
[7.92 ± 0.787]
0.040 ± 0.002
[1.02 ± 0.051]
0.312 ± 0.031
[7.92 ± 0.787]
0.040 ± 0.002
[1.02 ± 0.051]
0.375 ± 0.031
[9.53 ± 0.787]
0.040 ± 0.002
[1.02 ± 0.051]
S = Solderable, inductively wound
W = Weldable, inductively wound
120
100
N = Solderable, non-inductively wound
Z = Weldable, non-inductively wound
Terminals: Solderable - Tinned Copperweld®
Weldable - Bare Nickel per MIL-STD-1276, Type N-1
End Caps: Stainless Steel
Part Marking: Source Code, JAN, Military PIN,
Date/Lot Code
80
60
40
20
APPLICABLE MIL-SPECIFICATION
MIL-PRF-39007: This is the military specification
covering axial lead established reliability power
wirewound resistors.
Vishay Dale ESS, ESW, EGS, EGW, ESN and EGN
resistors meet or exceed the electrical, environmental
and dimensional requirements of this specification.
0
-65-50
0
50
150
250
25
AMBIENT TEMPERATURE IN °C
Derating
TECHNICAL SPECIFICATIONS
PARAMETER
UNIT
ppm/°C
VAC
ESS, ESW, ESN, EGS, EGW, EGN RESISTOR CHARACTERISTICS
± 650 for 0.1Ω to 0.499Ω, ± 400 for 0.505Ω to 1Ω, ± 50 for 1.1Ω to 10Ω, ± 20 for 10Ω and above
500 minimum for 2 watt and smaller, 1000 minimum for 3 watt and larger
Temperature Coefficient
Dielectric Withstanding Voltage
Short Time Overload
-
5 x rated power for 5 seconds for 3 watt size and smaller,
10 x rated power for 5 seconds for 5 watt size and greater
Maximum Working Voltage
Insulation Resistance
Terminal Strength
V
Ω
lb
-
(P x R)1/2
1000 Megohm minimum dry, 100 Megohm minimum after moisture test
5 minimum for 2 watt and smaller, 10 minimum for 3 watt and larger
Meets requirements of ANSI J-STD-002
Solderability
Operating Temperature Range
°C
- 65/+ 250
PERFORMANCE
TEST
CONDITIONS OF TEST
TEST LIMITS
Thermal Shock
Short Time Overload
MIL-STD-2.2, Method 303
5 x rated power (RWR71, 80, 81, 89, 82), 10 x rated power (RWR74, 78, 84) for 5 seconds
± (0.2% + 0.005Ω) ∆R
± (0.2% + 0.005Ω) ∆R
± (0.1% + 0.005Ω) ∆R
± (0.1% + 0.005Ω) ∆R
± (1.0% + 0.005Ω) ∆R*
± (0.2% + 0.005Ω) ∆R
± (0.1% + 0.005Ω) ∆R
± (0.1% + 0.005Ω) ∆R
± (0.5% + 0.005Ω) ∆R
± (1.0% + 0.005Ω) ∆R
Dielectric Withstanding Voltage 500Vrms (RWR80, 81, 82), 1000Vrms (RWR71, 74, 78, 84, 89), 1 minute duration
Low Temperature Storage
High Temperature Exposure
Moisture Resistance
Shock, Specified Pulse
Vibration, High Frequency
Load Life
- 65°C for 24 hours
250°C for 2000 hours
MIL-STD-202, Method 106
MIL-STD-202, Method 205, Condition C
MIL-STD-202, Method 204, Condition D
2000 hours at rated power, + 25°C, 1.5 hours “ON”, 0.5 hours “OFF”
10,000 hours at rated power, + 25°C, 1.5 hours “ON”, 0.5 hours “OFF”
Extended Life
MIL-STD-202, Method 211, Condition A and C
5 pound (RWR80, 81, 82), 10 pound (RWR71, 74, 78, 84, 89)
Terminal Strength
± (0.1% + 0.005Ω) ∆R
*For resistance values above 100 ohms, Test Limit is ± 1.0%.
Document Number 30203
Revision 23-Sep-02
For technical questions, contact ww2bresistors@vishay.com
www.vishay.com
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