Operation Manual

GMC-I Messtechnik GmbH 29
4 Performing Tests
Each of the following tests is automatically assigned to one cur-
rently available object number. Any given test which is saved to
memory with the “STORE” key is stored with reference to this
number. The object number can be entered in the “DUT data”
menu (see chapter 5.1 on page 48).
Measuring mode operation is always carried out according to the follow-
ing sequence:
• Select the desired test.
• Enter test parameters (if required).
• Start the measurement or return to the initial menu.
• Save measured values to memory and enter a description
(if desired).
Observe the following for all tests:
• Safety features and precautions, see chapter 2.
• Disconnect the device under test from all sources of voltage
first.
• Test for absence of voltage.
• Do not disconnect the measurement cables until the device
under test has been fully discharged.
4.1 Insulation (resistance) Test
Test voltage can be set between 100 V and 5,000 V for this test.
This voltage, as well as the allowable limit value for insulation
resistance, can be selected as a test parameter.
Voltage at the device under test appears at the LCD in addition to
measured insulation resistance.
Discharge
After the measurement has been completed, the device under
test is discharged automatically in order to assure zero voltage.
The falling voltage value can be observed at the display during the
discharging process. The measured insulation resistance value
remains in memory during this period of time.
Interference Voltage
If voltage is present at the test probes after mea-
surement is started, an “external voltage” warning
appears at the display. The level of the interference
voltage is shown at the display. The insulation test is aborted after
the test probes have been removed from the DUT. The test has to
be conducted again on the de-energized DUT.