GMC-I Messtechnik GmbH
45
Measurements R
SL
– M
ISO
@10 V/100 V – CAP
Switch positions (a-b) (a-E) (b-E)
6.3.3 Performing Insulation Resistance Measurements
Caution High-Voltage!
Do not touch the conductive ends of the test probes when the
instrument has been activated for the measurement of insula-
tion resistance. If at all possible, only plug in the measurement
cables actually required for this test, because loose test probes
and cable ends represent a contact hazard. You may otherwise
be exposed to a current of 1.5 mA (limited in the measuring
instrument), and although this is not life endangering, the result-
ing electrical shock is quite discernible. If, on the other hand,
measurement is being performed on a capacitive device under
test, for example a cable, it may be charged up to approxi-
mately ±120 V. Touching the device under test after measure-
ment has been performed is life endangering in this case!
➭
Starting the insulation resistance measurement
:
Briefly press the
U
ISO
ON / OFF
key.
Insulation resistance is displayed for the currently selected
conductor pair (analog display is logarithmic).
➭
Reversing polarity of the cable under test:
– Normal polarity reversal:
Press and hold the
POL / U
ISO
key.
– Rapid polarity reversal:
Press the
POL / U
ISO
key at short intervals. bAL.C appears at
the display (ballistic capacitance) for relative cable length
determination. After key activation has ceased for a period
of approximately 2 seconds, the instrument is switched
back to standard insulation resistance measurement.
➭
Switch the rotary selector switch to the M
ISO
_a-b, M
ISO
_a-
E and M
ISO
_b-E positions, one after the other, in order to
execute the desired tests.
0
00
.
00
M
M
a-b
a-E
b-E
M
ISO
@10V/100V
ISO
a-b
FUNC
ENTER
U
ISO ON
/ OFF
ZERO
ESC
POL / U
ISO
FUNC
ENTER
U
ISO ON
/
OFF
a-E
FUNC
ENTER
U
ISO ON
/ OFF
ZERO
ESC
POL / U
ISO
FUNC
ENTER
U
ISO ON
/
OFF
b-E
FUNC
ENTER
U
ISO ON
/ OFF
ZERO
ESC
POL / U
ISO
FUNC
ENTER
U
ISO ON
/
OFF
U
ISO
000
.
0
U
ISO
V
FUNC
ENTER
+
–
+
–
a
a
b
b
E
E
+
–
0 V !
Reverse polarity
Discharge
Switch
DC
AC
TRMS
100V
ISO 100V
test voltage on
Summary of Contents for METRAHIT T-COM PLUS
Page 5: ...GMC I Messtechnik GmbH 5 Standard Equipment Contact Persons ...
Page 11: ...GMC I Messtechnik GmbH 11 Safety Warnings ...
Page 25: ...GMC I Messtechnik GmbH 25 Control Functions ...
Page 41: ...GMC I Messtechnik GmbH 41 Measurements V Hz Temp m A Hz ...