鈼?/div>
Overload characteristics ideal
for protection circuits
Electrical Data
Commercial
Power rating at 25掳C
Resistance range at
1% tolerance
2% tolerance
5% tolerance
watts
ohms
ohms
ohms
pp/掳C
Style
watts
watts
ohms
ohms
ohms
ppm/掳C
W21
3.0
1 to 10k
0.5 to 10k
0.1 to 10k
W215
5.0
1 to 15k
0.5 to 15k
0.1 to 15k
Typically: <+75
W22
7.0
1 to 22k
0.5 to 22k
0.1 to 22k
W23
W24
10.0
14.0
1 to 60k
1 to 100k
1 to 60k
1 to 100k
0.15 to 60k
0.2 to 100k
Maximum: +200
TCR (-55掳 to 200掳C)
Approved BS CECC 40-201-002
Power rating at 25掳C
Power rating at 70掳C
Resistance range at
1% tolerance
2% tolerance
5% tolerance
TCR (-55掳 to 200掳C)
JB
HB
KB
LB
MB
2.9
5.0
7.0
10.0
14.0
2.5
4.3
6.0
9.0
12.0
1 to 10k
1 to 15k
1 to 20k
1 to 56k
1 to 100k
0.5 to 10k
0.5 to 15k
0.5 to 20k
1 to 56k
1 to 100k
0.1 to 10k
0.1 to 15k
0.1 to 20k
0.15 to 56k
0.2 to 100k
鈮?
ohms < 10 ohms: 卤400
鈮?0
ohms: 卤200
Applicable to commercial and approved ranges
Limiting element voltage
volts
Standard values
Thermal impedance
掳C/watt
Ambient temperature range
掳C
100
160
200
500
E24 preferred. Other values to special order
88
58
44
29
-55 to 200
750
22
Physical Data
Dimensions
Type
W21
W215
W22
W23
W24
400
(mm) & weight (g)
L max
D max
12.7
5.6
22.0
7.0
22.0
8.0
38.0
8.0
53.5
8.0
f min
22.75
23.1
23.1
-
-
d nom
0.8
0.8
0.8
0.8
0.8
Wt.nom
1
2
2
3.5
5
d dia
D
L
f
Temperature Rise
掳C
W21
W215
W22
W24
W23
CONSTRUCTION
A high purity 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; the vitreous enamel protective coating is then applied.
TERMINATIONS
Material
Copper clad steel wire, nickel plated and solder-coated.
Strength
The terminations meet the requirements of IEC 68.2.21.
Solderability
The terminations meet the requirements of IEC 115-1,鈥?/div>
Clause 4.17.3.2.
Length
W23鈥檚 and W24鈥檚 are not supplied on tape.
Minimum lead length is 30 mm.
MARKING
The resistors are legend marked with type reference, resistance value and tolerance.
Values are marked in accordance with IEC 62.
SOLVENT RESISTANCE
The body protection and marking are resistant to all normal industrial cleaning
solvents suitable for printed circuits.
300
200
100
0
0
5
10
15
20
Dissipation 鈥?Watts
General Note
Welwyn Components reserves the right to make changes in product specification without notice or liability.
All information is subject to Welwyn鈥檚 own data and is considered accurate at time of going to print.
漏 Welwyn Components Limited
Bedlington, Northumberland NE22 7AA, England Tel: 01670 822181 Fax: 01670 829465 Web: http://www.Welwyn-TT.co.uk
Issue A 07/99
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