Vitreous Enamelled
Wirewound Resistors
W20 Series
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•
•
•
•
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Electrical Data
This table indicates the CECC specification requirements, and these are met or exceeded by the corresponding W20 series products
Physical Data
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.
© Welwyn Components Limited
Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com
C
P
R
T
BS CECC 40-201-002 Requirements
P
P
R
T
Applicable to commercial and approved ranges
i L
S
T
A
Dimensions (mm) and Weight (g)
Type
W21
W215
W22
W23
W24
C
C
o
e
o
o
e
a t
h
o
CECC approved
Suitable for harsh environments
Impervious lead free vitreous enamel coating
Overload characteristics ideal
for protection circuits
High stability and reliability
High power dissipation for size
m
m
400
300
200
100
w
s i s
w
w
s i s
r e
R
R
m
n
t i
b
0
e
e
e
d
m
a t
(
a t
(
n i
e i
m
0
5 -
r r
r r
r r
5 -
a
a
g
t n
n
n
d r
r e
° 5
° 5
i l
t a
t a
t a
e c
e c
W21
e
Dissipation – Watts
i c
m
e t
n i
n i
n i
a v
e l
o t
o t
l a
a r
a r
p
m
g
g
g
m
u l
e
5
n
n
2
2
p
t a
t a
t a
e
W215
s e
d
L max
22.0
38.0
53.5
g
g
0
0
e
12.7
22.0
t n
a
e
e
° 0
° 0
a r
2
2
7
n
W22
t a
t a
v
° 5
° 5
° 0
e c
u t
) C
) C
l o
10
C
C
C
e r
a t
W23
g
1
2
5
1
2
5
a r
%
%
%
%
%
%
e
n
g
D max
15
o t
o t
o t
o t
o t
o t
e
5.6
7.0
8.0
8.0
8.0
W24
e l
e l
e l
e l
e l
e l
a r
a r
a r
a r
a r
a r
n
n
n
n
n
n
20
e c
e c
e c
e c
e c
e c
· Bedlington, Northumberland NE22 7AA, UK
22.75
f min
23.1
23.1
-
-
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
Strength
Solderability
Length
Marking
The resistors are legend marked with type reference, resistance value and tolerance. Values are
marked in accordance with IEC 62.
d nom
0.8
0.8
0.8
0.8
0.8
Wt.nom
p
°
/ C
Copper clad steel wire, nickel plated and solder-coated.
The terminations meet the requirements of IEC 68.2.21.
The terminations meet the requirements of IEC 115-1,– Clause 4.17.3.2.
W23’s and W24’s are not supplied on tape. Minimum lead length is 30 mm.
3.5
p
p
o
o
o
o
o
o
1
2
2
5
w
w
w
m
Style
p
o v
w
h
h
h
h
h
h
t a
t a
t a
° /
° /
m
m
m
m
m
m
a
°
s t l
s t
s t
s t
C
C
t t
C
s
s
s
s
s
s
0
0
0
0
1
1
R
R
R
R
R
R
5
1
5
1
W
o t
3
2
o t
1
2
o t
o t
JB
o t
o t
8
0 .
0
2
9 .
5 .
8
1
≥5 ohms < 10 ohms: ±400
0
1
1
1
1
1
1
0
0
0
0
0
0
K
K
K
K
K
K
T
E
p y
2
0
0
0
0
1
1
4
R
R
R
R
c i
R
R
d
W
5
1
5
1
r p
l a
o t
o t
5
HB
5
4
1
o t
o t
o t
o t
: y l
2
f e
5
0 .
0 .
3 .
6
1
8
1
1
0
r e
1
5
1
1
1
<
5
5
5
D
5
5
5
e r
+
K
K
K
K
K
K
-75
. d
O
0
0
0
0
1
1
5 -
h t
R
R
R
R
R
R
1
5
1
5
5
Welwyn Components
r e
W
o t
o t
7
KB
7
6
2
o t
o t
o t
o t
4
o t
0 .
0 .
0 .
0
2
a v
L
4
2
0
2
2
2
2
2
2
2
0
u l
2
2
2
0
0
0
K
K
s e
K
K
K
K
0
≥10 ohms: ±200
Maximum: +-200
o t
0
0
1
1
R
1
1
R
p s
R
R
1
R
R
1
W
5
5
c e
1
1
o t
o t
9
o t
o t
5
LB
0
0
2
o t
0 .
o t
0
l a i
2
0 .
0 .
9
f
0
6
6
5
5
3
6
0
0
6
6
5
o
0
K
K
K
K
6
d r
K
K
r e
TT electronics plc
0
0
1
1
1
1
R
A subsidiary of
R
R
R
R
R
2
2
W
o t
o t
1
1
1
o t
o t
o t
MB
o t
7
4
4
2
2
2
5
0 .
1
1
0 .
0 .
1
1
2
1
4
1
0
0
0
0
0
0
0
0
0
0
0
0
0
K
K
K
K
K
K
85