User Manual
GMC-I Messtechnik GmbH 17
6.6 Connection Tests Conducted by the Test Instrument
The following measurements are performed automatically when 
the DUT is connected to the test instrument.
• Connection test (detection of connection via either the test 
socket or the multimeter jack sockets)
• Protection class detection (with earthing contact connection 
only: detection of whether or not the protective conductor is 
connected)
• Short-circuit test
• On test (test of whether the device under test is switched on or 
off)
• Probe test (detection of whether or not test probe P1 is 
plugged in)
• Electronic fuse (test of whether or not the fuse in the DUT is 
tripped at a residual current of > 10 mA)
• Measurement of starting current (if starting current is greater than 
16 A after 200 ms, the following message appears: “Use an 
external adapter or another measuring method”)
Automatic Recognition of States when Connecting 
DUTs and Probes 
7 Notes on Saving Single Measurements and Test 
Sequences
At the end of each test, test results can be saved under an ID 
number which is unequivocally assigned to the respective DUT.
Depending on the initial situation, i.e. whether or not a test struc-
ture or database is already available or an ID has already been 
entered, the following different procedures are used for saving:
Variant 1 – pre-selection of an existing ID
You’ve already set up a test structure in the test instrument.
Open the database view before starting the measurement by 
pressing the MEM key. Then select the device under test or its ID 
within the test structure by pressing the respective scroll key. Exit 
the database view (MEM navigation) by pressing MEM and start the 
measurement. Press the Save as   key at the end of the mea-
surement. The display is switched to the SAVE view. The ID 
appears with a green or orange background. Press the Save   
key once again in order to complete the procedure.
Variant 2 – entry of an existing ID at the end of the test
You’ve already set up a test structure in the test instrument.
You perform the measurement without first opening the database. 
No device under test was previously selected in the database. 
Press the Save as   key at the end of the measurement. The fol-
lowing message appears: “No DUT selected!” Press the ID key. 
The softkey keyboard appears.
If you enter an ID here which is already in the database, the data-
base view appears (MEM navigation) automatically, and the DUT’s 
ID is displayed inversely. Acknowledge the entry by pressing the 
 key. The display is switched to the SAVE view. The ID appears 
with a green or orange background. Press the Save   key once 
again in order to complete the procedure.
Variant 3 – entry of a new ID at the end of the test
You haven’t yet set up a test structure in the test instrument, or 
the ID is not included in the existing structure.
Press the Save as   key at the end of the measurement. The fol-
lowing message appears: “No DUT selected!” Press the ID key in 
order to enter the DUT’s ID. The softkey keyboard appears.
If you enter an ID here which is not yet included in the database, a 
prompt appears asking you if you want to enter a new object.
–  : If you press  , the display is switched to the SAVE view. The 
ID appears with a green or orange background. Press the Save 
 key once again in order to complete the procedure. 
–  : If you press  , the database view appears (MEM naviga-
tion). Go to the next page (Edit objects 2/3) by pressing  , and 
then enter a new object. Press   to this end. All possible 
object types are displayed. Press “DUT”. The newly entered ID 
appears in red to the right of the ID parameter. Acknowledge 
the entry by pressing the   key. The display is switched to the 
database view (MEM navigation). The newly entered device 
under test is displayed inversely in the structure. Press MEM in 
order to return to the SAVE view. The ID appears with a green 
background. Press the Save   key once again in order to 
complete the procedure.
– ESC: If you don’t want to save any measured values, press 
ESC 
twice in order to go to the measuring view. If you press ESC 
again, a prompt appears asking whether or not you want to 
delete the measuring points in order to continue with the mea-
surement without saving.
Control function Condition
Short-circuit test Short-circuit / starting current R  1.5 Ω
No short-circuit (AC test) R > 1.5 Ω
On test On (DUT passive) R < 250 kΩ
Off (DUT active) R > 300 kΩ
Probe test No P1 test probe R > 2 MΩ
Test probe P1 detected R < 500 kΩ
Protection class detection
Protective conductor exists: PC I
R < 1 Ω
No protective conductor: PC II R > 10 Ω
Safety shutdown
Triggered at following residual current value (selectable)
> 10 mA / > 30 mA
Triggered at following probe current values
During leakage current measurement > 10 mA
During protective conductor resistance meas. > 250 mA
Connection test
Checks whether the DUT is connected to the test socket.
In the case of protection class I: checks whether the two protective 
conductor terminals are short-circuited.
Protective conductor exists R < 1 Ω
No protective conductor R > 10 Ω
Insulation test
DUT set up in a well-insulated fashion R 500 k
DUT set up in a poorly insulated fashion R < 500 k










