Burster RESISTOMAT 2408, Manual, Page: 79 / 90

Model 2408
RESISTOMAT
®
Page 79
3.4 Resistance Measurements
The recommended test voltage is typically 100 V for fixed composition resistors, film
resistors or wire wound resistors above 100 k
Ω
. Refer to the component manufacturers’
recommended test voltages. These resistors (values greater than 1000
Ω
) can easily be
measured on the 2408 where the instrument basic accuracy of 0.5% is adequate. For
single component resistors a two terminal connection, +UNKNOWN and -UNKNOWN is
recommended.
3.5 Measurement of Voltage Coefficient
The 2408 instrument may be used to measure voltage coefficient which is defined as:
R1 - R2
----------------- x 100%
R2 (V1 - V2)
where V1>V2
R1 is the resistance at V1, the higher voltage
R2 is the resistance at V2
For example, if V1 = 500 V and V2 = 100 V,
R
500V
– R
100V
Voltage Coefficient = ----------------- x 100%
R
100V
(400)
∆
R
= ¼ ------- %
R
100V
This voltage coefficient is usually negative.