User manual

8 GMC-I Messtechnik GmbH
5 Descriptions of Individual Measurements
5.1 Measurements at the Test Outlet(s)
Protective Conductor Resistance, R
PE
SOCKET
The probe must be plugged into the
PROBE PE/I
C
socket for the measurement of
protective conductor resistance. Measure-
ment is performed between the protective
conductor terminal at the test outlet and the
PROBE PE/I
C
socket.
Protective Conductor Resistance, R
PE
FIX
This measurement is used for testing the
protective conductor at permanently con-
nected devices. The test instrument must be
connected to the same supply circuit as the
device under test during measurement.
Attention!
!
Good test results may be obtained
with parallel ground connections,
although the protective conductor is
interrupted.
The probe must be plugged into the
PROBE PE/I
C
socket for the measurement of
protective conductor resistance. Measure-
ment is performed between the protective
conductor terminal at the mains connection
and the PROBE PE/I
C
socket.
Testing is performed up through a resistance
value of approximately 1.3 Ω with automatic
polarity reversal.
The earthing contact resistance and the test
current are indicated on the LCD (not for
MINITEST Base).
Checking the Zero Point and the Fuse
The zero point and the internal fuse can be
checked by inserting the plug attached to
the test probe cable into the PROBE R
ISO
socket and the tip of the test probe into the
PROBE PE/I
C
socket with the selector switch in
the R
PE
SOCKET or R
PE
FIX setting. The dis-
played value should not exceed 100 mΩ.
Note: If a current of 0 mA is indicated, the
fuse is usually defective. Test and replace it,
if required.
Attention!
!
It is absolutely essential to insert the
tip of the test probe into the
PROBE PE/I
C
socket for this test!
Attention!
!
Use only the probe cable which is
included with the test instrument. If a
different probe cable is used:
– The measured value may be
distorted.
– The test instrument may be
damaged.
– Malfunctioning may occur.
Insulation Resistance, R
ISO
Various test types are provided for the mea-
surement of insulation resistance.
The test type is selected automatically when
the test probe is plugged into the probe
connector socket (10).
The original test probe cable must be used
in order to take advantage of this function.
Test type switching cannot be assured if
other test probe cables are used.
• For safety class I DUTs without exposed
conductive parts:
Test insulation between L/N and PE at
the test outlet.
The test probe cable may not be plugged into
the PROBE R
ISO
socket for this test!
• For safety class II DUTs, or for safety
class I DUTs with exposed conductive
parts which are not connected to the
protective conductor:
Test between L/N at the test outlet and
the PROBE R
ISO
socket.
The test probe must be plugged into the
PROBE R
ISO
socket for this test!
The insulation resistance and the test volt-
age are indicated on the LCD (not for
MINITEST Base).