W30 Datasheet, PDF (1/2 Pages) Welwyn Components Limited – Cement Coated Wirewound Resistors

Cement Coated
Wirewound Resistors
W30 Series
• Values down to 10m ohms
• ^{Tolerance to 1%}
• ^{Flameproof protection}
• ^{Custom built to meet pulse requirements}
Welwyn Components
Electrical Data
Power rating at 25°C
Power rating at 70°C
Resistance range
TCR (-55 to 155°C)
Resistance tolerance
Standard values
Thermal impedance
Ambient temperature range
Limiting element voltage
TCR
watts
watts
ohms
ppm/°C
%
°C/watt
°C
volts
ppm/°C
W31
3.0
2.5
0R01 to 10K
See below
521
E24 series preferred
83
-55 to 155
100
0.01 ohms <1000
0.033 ohms <500
0.091 ohms <200
10 ohms <150
10K ohms <100
Notes
Other values to special order
Physical Data
Maximum Dimensions (mm) and Weight (g)
Type
L max. D max. f min.
W31
13
5.6
22.75
d nom.
0.8
Wt.nom.
1.0
dD
L
f
Construction
A high quality ceramic substrate is assembled with
interference fit end caps to which are welded the element
winding and termination wires. The protection is then applied
to the body, providing an effective seal which is impervious to
moisture, shock, vibration, fungus and salt spray.
Terminations
Material
Solder coated copper.
Strength
The terminations meet the requirements of
IEC 68.2.21.
Solderability The terminations meet the requirements of
IEC 115-1, Clause 4.17.3.2.
Marking
W31 resistors are legend marked with type reference,
resistance value and tolerance. Values are marked in
accordance with IEC 62.
Solvent Resistance
The body and marking are resistant to all normal industrial
cleaning solvents suitable for printed circuits.
Flammability
The resistor coating will not burn under any condition of
applied temperature or component overload.
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 · Bedlington, Northumberland NE22 7AA, UK
Telephone: [phone] · Facsimile: [phone] · Email: [e-mail] · Website: www.welwyn-tt.com
A subsidiary of
TT electronics plc
Issue D · 07.06
99