General Purpose Cement
Coated Wirewound Resistors
WA80 Series
Welwyn Components
•
Cost effective
•
Flameproof protection
•
Can replace carbon comp. in many applications
•
Resistance values down to 0.01 ohms
•
Ideal for pulse handling applications
Electrical Data
WA82
Power rating at 25°c
Power rating at 70°c
Resistance range
Limiting element voltage
Isolation voltage
TCR
Resistance tolerance
Values
Thermal impedance
Ambient temperature range
°C/watt
°C
140
110
82
- 55 to 155
watts
watts
ohms
volts
volts
ppm/°C
%
1
.86
0R068 to 430
50
250
WA83
2.0
1.6
0R05 to 900R
50
250
<1Ω:350
<20R: 5, 10
≥20R:
1, 2, 5, 10
90
54
35
E24 preferred
WA835
2.5
2.0
0R05 to 900R
75
250
WA84
3.0
2.5
0R01 to 2K2
100
350
WA85
5
4.3
0R015 to 6K8
150
500
>1Ω:200
WA87
7
6
0R15 to 10K
150
700
Physical Data
Dimensions (mm) and Weight (g)
PCB
mounting
centres
10.20
12.70
18.40
20.30
22.86
31.40
Min
bend
radius
0.6
1.2
1.2
1.2
1.2
1.2
Wt
nom.
0.22
0.50
0.50
1.10
1.75
4.40
d
D
L
f
Type
WA82
WA83
WA835
WA84
WA85
WA87
L max.
6.2
9.0
12.5
14.5
16.5
25.0
D max.
2.8
3.6
4.5
5.2
7.0
8.8
f min.
21.20
19.80
17.80
24.55
23.55
28.30
d nom.
0.6
0.8
0.8
0.8
0.8
0.8
Construction
A high quality ceramic substrate is assembled with
interference fit end caps to which are welded the termination
wires. The resistive element is wound on the substrate and
welded to the caps. Cement protection is applied to the
resistor body before marking with indelible ink.
Terminations
Material
Strength
Solder-coated copper wire on 82, 83, 835, 84,
and 85, solder coated cooper clad steel on 87.
The terminations meet requirements of
IEC 68.2.21.
Solderability
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 · 08.04
© 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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