Rev Date: 07/27/2012 1 www.seielect.com
This specification may be changed at any time without prior notice marketing@seielect.com
Please confirm technical specifications before you order and/or use.
WRF Series
Conformal Coated Wirewound Resistor
Stackpole Electronics, Inc.
Resistive Product Solutions
Features:
‱ Conformal coating
‱ Flameproof construction
‱ Cut and formed product is available on select sizes
Contact factory for details
‱ RoHS compliant / lead-free
Maximum Dielectric
Working Withstanding
Voltage Voltage (RMS)
WRF1 1W √PR 700V -80ppm/ÂșC ~ +900ppm/ÂșC 0.1 - 33
WRF2 2W √PR 700V -80ppm/ÂșC ~ +900ppm/ÂșC 0.1 - 220
WRF3 3W √PR 700V -80ppm/ÂșC ~ +900ppm/ÂșC 0.1 - 220
Type / Code Power Rating
(Watts) @ 25ÂșC
Resistance Temperature
Coefficient
Ohmic Range (℩ )
and Tolerance
5%
Electrical Specifications
Test Results
85ÂșC
Open circuit within 2 minutes
± 3% + 0.05℩
± 2% + 0.05℩
>10
4
M℩
± 2% + 0.05℩
± 5% + 0.05℩
± 5% + 0.05℩
± 1% + 0.05℩
90% tin covered min.
-80ppm/ÂșC ~ +900ppm/ÂșC
Operating Temperature Range: -55ÂșC to +200ÂșC (WRF 1, 2)
-55ÂșC to +225ÂșC (WRF 3)
Load Life @ 70ÂșC - 1,000 hrs.
Moisture Resistance
Shock and Vibration
Temperature Coefficient
Solderability
Short Time Overload
Effective Soldering
Insulation Resistance
Dielectric Withstanding Volt
Test
Rated Ambient Temperature
Overload 15 Times the Rated Wattage
0.433 max 0.197 max 1.102 ± 0.118 0.031 ± 0.002 inches
11.00 max 5.00 max 28.00 ± 3.00 0.78 ± 0.05 mm
0.630 max 0.197 max 1.102 ± 0.118 0.031 ± 0.002 inches
16.00 max 5.00 max 28.00 ± 3.00 0.78 ± 0.05 mm
0.630 max 0.197 max 1.102 ± 0.118 0.031 ± 0.002 inches
16.00 max 5.00 max 28.00 ± 3.00 0.78 ± 0.05 mm
Body Width
C
Lead Length (Bulk)(1)
D
Lead Diameter
(1) See "Resistor Packaging Specification Document" for lead length dimension for tape and reel packaged product.
WRF3
WRF1
Type / Code Unit
WRF2
A
Body Length
B
Mechanical Specifications
Performance Characteristics
Rev Date: 07/27/2012 2 www.seielect.com
This specification may be changed at any time without prior notice marketing@seielect.com
Please confirm technical specifications before you order and/or use.
WRF Series
Conformal Coated Wirewound Resistor
Stackpole Electronics, Inc.
Resistive Product Solutions
Power Derating Curve:
0
25
50
75
100
30050 100 150 200 250
85 225
Percent Rated Power (%)
Ambient Temperature (ÂșC)
WRF3
WRF1, WRF2
12345678910
WRF 2 J B1 0 R 0
Code Nominal Resistance
2 10R
T
y
pe Description Code Tol
V
alues T
y
pe Pk
g
Qt
y
Description Code
WRF Conformal Coated WW 1 5% E24 All 1,000 Bulk A
2 All 2,000 Tape and Reel R
3 All 1,000 Ammo T
WRF
SEI Type
A
PackagingTolerance
5%
Size
1Code
Value Quantity
2J
E24 2,000
3
Product Series Power Rating Resistance ValuePackaging
Four characters with
the multiplier used as
the decimal holder.
2W 5%
Ammo3W
Bulk
Size1W Tol
Tape and Reel
0.1 ohm = R100
1 ohm = 1R00
100 ohm = 100R
Code
T
A
B
F
Tolerance
1,000All Sizes
All Sizes
DescriptionConformal
Coated WW
WR
How to Order
Legacy Part Number (before January 3, 2011):