Ultra Precision Bulk Metal
Film Resistors
Welwyn Components
4800 series
Physical Data
Dimensions (mm) & Weight (g)
4802/12/04/05
L
W
Type
L max
H max
10.2
8
W max
3.8
T min
30
d nom
0.6
S nom Wt. nom
4802
4812
4804
4805
4832
8.9
5.1
5.1
1
H
T
7.5
2.5
30
0.6
0.6
1.5
2
d dia
15.2
22.6
9.7
13.2
13.2
5.4
3.8
30
0.6
10.2
17.8
1.5
S
4832
3.8
30
0.6
d
H
S
9.7
30
0.6
1.1
L
W
T
Terminations
Material
Strength
Construction
Solder coated 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.
The resistor element is an etched bulk metal foil, bonded to
an alumina substrate. Connections to the foil are made by
copper wires welded to the foil to minimise thermal e.m.f.
Before encapsulation, the resistor element is coated with
silicone rubber to isolate the element from mechanical stress
which would adversely affect the carefully balanced
construction and result in poor resistance/temperature
characteristics.
Solderability
Marking
Type reference, resistance value, tolerance and date code are
legend marked. The resistance value conforms to IEC 62.
Solvent Resistance
The protection will withstand all normal industrial solvents
suitable for cleaning printed circuit boards.
Performance Data
Actual
Maximum
0.05
Typical
0.02
Load at commercial rating: 1000 hours at 70°C
Dry heat: 1000 hours at 155°C
Shelf life: 12 months at room temperature
Derating from rated power at 70°C
Short term overload
∆R%
∆R%
∆R%
0.05
0.02
0.0025
Zero at 155°C
55/155/56
∆R%
0.01
0.005
Climatic category
Climatic
∆R%
∆R%
∆R%
∆R%
∆R%
µV/V
0.05
0.05
0.01
0.01
0.01
0.03
0.03
Long term damp heat
Temperature rapid change
Resistance to solder heat
Vibration and bump
0.005
0.005
0.005
Noise. (in a decade of frequency)
Below level of
practicable measurement
>1000M
Voltage coefficient of resistance
Insulation Resistance
Inductance
ppm/V
ohms
µH
0.2
1
0.08
0.5
Capacitance
pF
Packaging
All components are supplied loose packed in either plastic bags
or panel boxes. Quantity per box will depend on resistor size.
© 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 B · 03.02
187