
MH25
MH37
Power rating at 70°C max
watts
0.25
0.5
Resistance range
ohms
100K - 10M
100K - 3M
Limiting element voltage
volts dc or ac peak
1,600
3,500
Isolation voltage
volts
700
TCR
ppm/°C
100
Resistance tolerance
%
1, 2, 5
Standard values
E24 and E96 preferred
Thermal impedance
°C/watt
140
112
Ambient temperature range
°C
- 55 to 155
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: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com
Electrical Data
Issue E · 10.05
A subsidiary of
TT electronics plc
Welwyn Components
191
Construction
Thin film material is sputtered on to high grade ceramic rods.
Nickel 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 protection applied so that the terminations
remain completely clear.
Marking
1% tolerance resistors are colour coded with 5 bands.
2% and 5% tolerance have 4. Band IEC 62 colours are used.
Terminations
Material
Solder-coated copper wire.
Strength
The terminations satisfy the requirements of
IEC 68.2.21.
Solderability
The terminations meet the requirements of
IEC 115-1, Clause 4.17.3.2
Solvent resistance
The body protection and marking are resistant to all normal
industrial cleaning fluids suitable for printed boards.
Dimensions (mm) and Weight (g)
PCB
Min
Bend
Radius
mounting
centres
Type
L max
D max
f min
d nom
Wt.nom
MH25
6.2
2.5
21.0
0.6
10.2
0.6
0.3
MH37
9.0
3.7
19.6
0.8
12.7
1.2
0.5
Physical Data
L
D
f
d
High Voltage
Metal Film Resistors
MH Series
BSEN 60065 Approval for MH37
in value range 680K to 3M
High working voltage to 3.5KV
Small size
High pulse load capability
Robust cement coating
Value up to 10M