WRF Series
Conformal Coated Wirewound Resistor
Features:
•
•
•
•
Conformal coating
Flameproof construction
Cut and formed product is available on select sizes
Contact factory for details
RoHS compliant / lead-free
Stackpole Electronics, Inc.
Resistive Product Solutions
Electrical Specifications
Type / Code
WRF 1
WRF 2
WRF 3
Power Rating
(Watts) @ 25ºC
1W
2W
3W
Maximum
Working
Voltage
√PR
√PR
√PR
Dielectric
Withstanding
Voltage (RMS)
700V
700V
700V
Resistance Temperature
Coefficient
-80 ppm/ºC ~ +900 ppm/ºC
-80 ppm/ºC ~ +900 ppm/ºC
-80 ppm/ºC ~ +900 ppm/ºC
Ohmic Range (Ω)
and Tolerance
5%
0.1 - 33
0.1 - 220
0.1 - 220
Mechanical Specifications
Type / Code
WRF 1
WRF 2
WRF 3
A
Body Length
0.433 max
11 max
0.630 max
16 max
0.630 max
16 max
Power Derating Curve
B
Body Width
0.197 max
5 max
0.197 max
5 max
0.197 max
5 max
C
Lead Length (Bulk)
1.1 ± 0.08
28 ± 3
1.1 ± 0.08
28 ± 3
1.1 ± 0.12
28 ± 3
D
Lead Diameter
0.031 ± 0.002
0.78 ± 0.05
0.031 ± 0.002
0.78 ± 0.05
0.031 ± 0.002
0.78 ± 0.05
Units
inches
mm
inches
mm
inches
mm
Performance Characteristics
100
75
50
WRF 3
WRF 1, 2
25
Test
Rated Ambient Temperature
Overload 15 Times the Rated Wattage
Short Time Overload
Effective Soldering
Insulation Resistance
Dielectric Withstanding Volt
Load Life @ 70ºC - 1,000 hrs.
Moisture Resistance
Shock and Vibration
Solderability
Temperature Coefficient
200
225
250
300
Test Results
85ºC
Open circuit within 2 minutes
± 3% + 0.05Ω
± 2% + 0.05Ω
4
>10 MΩ
± 2% + 0.05Ω
± 5% + 0.05Ω
± 5% + 0.05Ω
± 1% + 0.05Ω
90% tin covered min.
-80 ±900 ppm/ºC
Percent Rated Power (%)
0
50
85 100
150
Ambient Temperature (ºC)
Operating Temperature Range: -55ºC to +200ºC (WRF 1, 2)
-55ºC to +220ºC (WRF 3)
How to Order
SEI Type
Code
Nominal Resistance
Tolerance
Packaging
WRF
Type
WRF
Description
Conformal Coated WW
2
Code
1
2
3
1.1K
5%
Tolerance
5%
Values
E24
Type
All
All
All
Pkg Qty
1,000
2,000
1,000
A
Description
Bulk
Tape
Ammo
Code
A
R
T
Rev Date: 04/22/2010
This specification may be changed at any time without prior notice
Please confirm technical specifications before you order and/or use.
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