Vitreous Enamelled
Wirewound Resistors
W20 Series
•
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•
•
•
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High stability and reliability
High purity ceramic substrate
High power dissipation for size
Suitable for harsh environments
Rugged all-welded construction
Impervious lead free vitreous enamel coating
Overload characteristics ideal for protection circuits
Electrical Data
IRC
Type
Power Rating
@ 25°C
(watts)
Resistance
Range
(ohms)
1 - 10K
W21
3.0
0.5 - 10K
0.1 - 10K
1 - 15K
W215
5.0
0.5 - 15K
0.1 - 15K
1 - 20K
W22
7.0
0.5 - 20K
0.1 - 20K
1 - 60K
W23
10.0
1 - 60K
0.15 - 60K
1 - 100K
W24
14.0
1 - 100K
0.2 - 100K
*See temperature rise graph
Tolerance
(±%)
1
2
5
1
2
5
1
2
5
1
2
5
1
2
5
TCR
(-55°C to 200°C)
(±ppm/°C)
Typical: <+75
Maximum: +200
Limiting
Element
Voltage
(volts)
Thermal
Impedance*
(°C/watt)
Operating
Temperature
Range
(°C)
100
88
-55 to 350
Typical: <+75
Maximum: +200
160
58
-55 to 350
Typical: <+75
Maximum: +200
200
44
-55 to 350
Typical: <+75
Maximum: +200
500
29
-55 to 350
Typical: <+75
Maximum: +200
750
22
-55 to 350
General Note
IRC reserves the right to make changes in product specification without notice or liability.
All information is subject to IRC’s own data and is considered accurate at time of going to print.
Wire and Film Technologies Division
• 4222 South Staples Street • Corpus Christi Texas 78411 USA
Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com
A subsidiary of
TT electronics plc
W20 Series Issue December 2008 Sheet 1 of 4
Vitreous Enamelled
Wirewound Resistors
Physical Data
d dia.
D
L
f
Dimensions (mm) and Weight (g)
IRC Type
W21
W215
W22
W23
W24
L
max
12.7
22.0
22.2
38.0
53.5
D
max
5.6
7.0
8.0
8.0
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
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.
Length:
W23’s and W24’s are not supplied on tape. Minimum length is 30mm.
MARKING
The resistors are legend marked with type reference, resistance value and tolerance.
SOLVENT RESISTANCE
The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed
circuits.
Wire and Film Technologies Division
• 4222 South Staples Street • Corpus Christi Texas 78411 USA
Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com
W20 Series Issue December 2008 Sheet 2 of 4
Vitreous Enamelled
Wirewound Resistors
Temperature Rise Curve
400
W22
W215 W22
W23
W24
Temperature Rise (°C)
300
200
100
0
5
10
15
Dissipation (watts)
20
Environmental Data
Test
Load at Commercial Rating: 1000 Hours @ room temperature
Dry Heat: 1000 hours @ 200°C
Shelf Life: 12 months at room temperature
Short Term Overload
Climatic
Long Term Damp Heat
Temperature Rapid Change
Resistance to Solder Heat
Vibration and Bump
Noise (In a Decade of Frequency)
Robustness
Insulation Resistance
Voltage Proof
∆R%
∆R%
∆R%
∆R%
∆R%
∆R%
∆R%
∆R%
∆R%
µV/V
∆R%
ohms
volts
Actual Performance
Maximum
5
2
0.03
.47
0.5
0.05
0.5
0.25
0.25
zero
0.4
>1 G ohm
500 min
Typical
3.5
1
0.02
0.1
0.2
0.02
0.2
0.03
0.05
zero
0.05
>1 G ohm
500 min
APPLICATION NOTES
The terminations should not be bent closer than 1.6mm from the body, and the recommended minimum bend
radius is 1.2 mm. Terminations are solderable to within 4mm from the body.
When cold, vitreous enamel has excellent insulation resistance. In common with all insulations the specific re-
sistance of the enamel decreases with increase in temperature. Therefore, resistors operated at near maximum
temperature cannot be classed as insulated and should not be used in contact with any conducting material.
Care must be taken when determining clearance distance between the resistor body and printed circuit board or
other components to ensure these are not overheated. Resistance is measured 6mm from the resistor body.
Wire and Film Technologies Division
• 4222 South Staples Street • Corpus Christi Texas 78411 USA
Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com
W20 Series Issue December 2008 Sheet 3 of 4
Vitreous Enamelled
Wirewound Resistors
Packaging
For W21, W215, and W22 resistors the standard method of packaging is taped in ammo packs. Alternatives
available by special request are:
- Taped and reeled
- Loose packed in boxes (minimum lead length 30mm). W23’s and W24’s are available only as loose
packed in boxes.
6
f1
b
6
f2
10 ± 0.5
Type
W21
W215
W22
Body location: f1 - f2
≤
1.4mm
A
63 ± 2
73 ± 2
73 ± 2
Standard Quantities Per Package
Type
Ammo Pack
Reel
Small Box
Large Box
Code
A
R
SB
LB
W21
1000
1000
200
800
W215
600
800
100
500
W22
500
700
100
300
W23
---
---
50
---
W24
---
---
25
---
Ordering Data
Specify type, reference, etc. as indicated in this example of
W21, 0.1KΩ, 5%, taped and ammo packed.
Sample Part No.
IRC Type
Value
Tolerance Code
J = 5%, G = 2%, F = 1%
W21
9K1
J
A
Packaging Details
Wire and Film Technologies Division
• 4222 South Staples Street • Corpus Christi Texas 78411 USA
Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com
W20 Series Issue December 2008 Sheet 4 of 4
