User Manual

32 GMC-I Messtechnik GmbH
Protection Class I Devices with Outputs for Safety Extra-Low Voltage
and Exposed Conductive Parts

– M
easurement type LN(TS) - P1 
– DUT mains plug to test socket 
– Test probe P1 to P1 terminals
Schematic Diagram
Insulation resistance is measured successively between short-cir-
cuited mains terminals (L-N) and the sa
fety extra-low voltage out-
puts which can be contacted with t
est probe P1, as well as exter-
nal conductive parts which are not connec
ted to the housing.
If measuring points should be contact
ed one after the other, this
is indicated by a dashed line. However, there are two parallel
measuring circuits for the RISO measurement with the LN(PD) –
P1//PE(PD) measuring parameter, which are established simulta-
neously to the short-circuited L and N conductors: one insulation
r
esistance is measured via PE at the test socket and, at the same
time, a second insulation resistance is measured via test probe
P1.
Wiring Diagram
2-Pole Measurement at Protection Class I Housing Parts 
(only with SECUTEST PRO or feature H01)
– M
easurement type P1 - P2
Schematic Diagram
Insulation resistance is measured between external conductive
parts which can be contacted with test probe P2 and are not con-
nected to the housing, and the housing with test probe P1.
Wiring Diagram
Special Case: Permanently Installed Protection Class I Devices 
– M
easurement type PE(mains) - P1 
– Test probe P1 to P1 terminals
Schematic Diagram
Insulation resistance is measured successively between PE at the
mains connection and the extra-low voltage inputs by contacting
each of them with test probe P1.
Wiring Diagram
Attention!
!
Deactivate the electrical system which supplies power to
the device under test before connecting the test instru
-
ment!
➭ Remove the mains fuses from the device under test and dis-
connect neutral conductor N inside the device under test.
➭ Connec
t test probe P1 to phase conductor L at the device
under test in order to measure insulation resistance.