Aluminium Housed
Wirewound Resistors
WH Series
Welwyn Components
•
High power dissipation for size
•
All welded construction
•
Suitable for severe environments
•
Designed for excellent thermal
conductivity to heatsink
Electrical Data
WH5
Power rating at 25°C
Resistance range
TCR (-55° to 200°C)
Resistance tolerance
Low value limits
watts
ohms
ppm/°C
%
ohms
1 at 1%
AA
10
0.05 to 3.4k
10
0R01 to 10K
<10Ω : ±75
WH10
15
0R01 to 20K
≥
to <100 : ±50
1, 2, 5, 10
0.5 at 2%
BA
15
0.05 to 15k
≥5Ω ≤
10Ω ± 100
1, 2, 5
1 at 1%
150
16.0
250
10.0
-55 to 200
0.5 at 2%
0.05 at 5%
500
6.0
1250
Other values to special order
3.5
Mounted on standard heatsink
WH50 0.015 at 10%
0.05 at 5%
CA
25
0.05 to 33k
>10Ω ± 50
0.01 at 10%
DA
40
0.05 to 82k
Mounted on standard heatsink
WH50 0.015 at 10%
WH25
25
0R01 to 44K
≥100Ω
: ±25
WH50
50*
0R015 to 120K
Notes
Mounted on standard heatsink
Approved CECC 40203 - 006
Power rating at 25°C
Resistance range
TCR (-55° to 200°C)
Resistance tolerance
Low value limits
Limiting element voltage
Standard values
Thermal impedance
°C/watt
°C
Ambient temperature range
watts
ohms
ppm/°C
%
ohms
volts
E24 preferred range
*For load at maximum rating mount on heatsink 30.5 cm x 30.5 cm x 1.5 mm
Construction
Cap and lead assemblies are fitted to a high purity ceramic
substrate. The resistive element is wound onto the substrate
and welded to the caps. The wound rod is then moulded and
fitted into an aluminium housing to give optimum stability
and reliability.
Marking
The resistors are legend marked with type reference,
resistance value and tolerance which will withstand all
accepted industrial cleaning fluids. Values are marked in
accordance with IEC 62.
Terminations
Material
Strength
Solderability
Solder dipped, copper clad steel wire.
The terminations meet the requirements of
IEC 68.2.21
The terminations meet the requirements of
IEC 115-1, Clause 4.17.3.2
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 D · 03.06
© 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
107
WELWYN [ WELWYN COMPONENTS LIMITED ]
