Operation Manual

GMC-I Messtechnik GmbH 39
Measurements: V/Hz – R
SL
– Ω – – Temp – – m – M Ω
ISO
– A/Hz
5.8 Insulation Resistance Measurement:
in Telecommunications Networks – MΩ
ISO
Function
Three jacks (a, b and E) are provided for measurements in
symmetrical copper cable networks with two conductors and a
shield. The rotary selector switch can be set to determine whether
insulation testing will be performed between a and b, a and E or
b and E.
Interruption of a single core or contact with an open-circuit core
(capacitive asymmetry) can be recognized by switching rapidly
with the POL / U
ISO key.
In the event of a good cable, the bar graph must be identical in the
a-E and b-E selector switch positions (open-circuit cable only!).
Long cable: long bar graph display
Short cable: short bar graph display
The overall length of the bar graph represents a range of
capacitance from 50 nF to 100 nF.
COM mA A
V
Tem p
Ω
aEb
0V !
!
10.38
F
+
–
+
–
μ
Measuring range: 10 pF to 300 μF
3.100 km / 31.000 km
Measuring ranges:
COM mA A
V
Temp
Ω
aEb
m
15.00
m
m
k
FUNC
ENTER
5 ranges: 30 nF, 300 nF,
3 μF, 30 μF and 300 μF