General Purpose Power
Wirewound Resistors
PW Series
Welwyn Components
•
20 watts to 50 watts
•
0.10 ohms to 2.0K ohms
•
±10% or ±5% tolerance
•
Customs
Electrical Data
PW-20E
Power rating at 25°C
Resistance range
watts
ohms
20
0R1 to 2K
PW-30
30
0R5 to 1K2
PW-40
40
0R65 to 1K5
PW-50E
50
0R08 to 1K8
Please note: When ordering the alternative configuration please add an ‘A’ after the part number. (i.e., PW-2A)
Dimensions (Inches)
A ±0.030
PW-20E
1.875
PW-30
2.00
PW-40
2.45
PW-50E
3.075
PW-20E Wirewound
B ±0.060
2.50
2.55
3.00
3.625
0.250 (Typ.)
5/32 Dia. Thru (2)
0.032±0.0025
PW-30, 40 and 50E Wirewound
5/32 Dia. Thru (2)
A
A
0.282±0.020
0.032±0.0025
0.157±0.020
0.75±0.030
0.25
B
0.375
0.75
0.5±0.030
0.5±0.030
0.75±0.030
0.875
Power Derating
100
Percent of Rated Load
80
60
PW-20E, PW-30, PW-40
PW-50E without bracket
0.205 or 0.187±0.005
0.125±0.015
0.200 (Typ.)
40
20
0
0.069±0.005
0.25±0.031
0.135±0.015
0
50
100
150
200
Ambient Temperature (°C)
250
PW-20E Alternate Terminal Configuration
Printed Circuit Terminal
With Bracket:
PW-30 Increased to 40 watts
PW-40 Increased to 50 watts
PW-50 Increased to 60 watts
PW-15E
0.500±0.030
0.020
0.250 min.
Temperature Rise
300
Temperature Rise (°C)
PW-50E
250
2.000±0.040
1.410±0.040
200
PW-20E
150
100
50
0
0
25
50
75
100
Percent of Rated Load
125
PW-30
PW-40
0.060 Dia. (2)
0.187±0.010
1.050 Min.
0.840±0.040
0.500±0.030
General Note
Welwyn Components reserves the right to make changes in product specification without notice or liability.
All information is subject to Welwyn’s own data and is considered accurate at time of going to print.
A subsidiary of
TT electronics plc
Issue B · 03.02
© Welwyn Components Limited
· Bedlington, Northumberland NE22 7AA, UK
Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com
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