High Voltage
Thick Film Resistors
VRW Series
•
VRW37 meets the requirements of BS / EN /
IEC 60065
•
High working voltage to 3.5kV in compact
size
•
High ohmic range to 30M
•
High pulse load capability
•
Robust flameproof coating material
•
RoHS compliant
Welwyn Components
Electrical Data
VRW25
Power rating at 70˚ C
Resistance range
Limiting element voltage
Isolation voltage
TCR
Resistance Tolerance
Standard Values
Thermal Impedance
Ambient temperature range
˚ C/watt
˚C
140
-55 to +155˚ C
watts
(Ohms)
volts dc or ac peak
volts
ppm/˚ C
%
0.25
100K to 30M
1600
700
200
1, 2, 5
E24 preferred
112
VRW37
0.5
100K to 10M
3500
Physical Data
Type
L
Max
6.2
9.0
(Dimensions (mm) & Weight (g)
f
min
21
19.6
d
Nom
0.6
0.8
PCB
mount
centres
10.2
12.7
Min
bend
radius
0.6
1.2
Wt.
nom
0.3
0.5
d
D
D
Max
2.5
3.7
VRW25
VRW37
L
f
Construction
Resistive thick film material is applied to high-grade ceramic
rods. Tin-plated steel caps are force fitted and the
termination wires are welded to the caps. The value is
obtained by a helical cut in the film and finally the resistor
body is protected by a cement coating applied so that the
terminations remain completely clear.
Terminations
Material:
Strength:
Solderability:
Hot tin dipped copper wire
The terminations meet the requirements
of IEC 68.2.21
The terminations meet the requirements
of IEC 115-1 Clause 4.17.3.2
Marking
1% tolerance resistors are colour coded with 5 bands. 2%
and 5% tolerance have 4 bands. IEC62 colours are used.
Marking
The body protection 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 power 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.
A subsidiary of
TT electronics plc
© 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
Issue D · 01.07
Issue C 07.06
70
WELWYN [ WELWYN COMPONENTS LIMITED ]
