Manual

52 Gossen Metrawatt GmbH
12.5 Testing of RCD Protection in IT Systems with High Cable
Capacitance (e.g. In Norway)
The desired system type (TN/TT or IT) can be selected for RCD
test type U
IN
(I
N
, t
a
), and for earthing measurement (R
E
).
A probe is absolutely essential for measurement in IT systems,
because touch voltage U
IN
which occurs in these systems can-
not otherwise be measured.
After selecting the IT system setting, connection with probe is
selected automatically.
Set Parameter – Select System Type
Start Measurement
12.6 Testing of 6 mA Residual Current Devices RDC-DD/RCMB
(RDC-DD: PROFITEST MXTRA and PROFITEST MTECH+
only)
DIN VDE 0100-722 (Requirements for special installations or
locations – Supplies for electric vehicles) specifies that all outlets
for charging electric vehicles must be protected by a separate
residual current device (RCD).
Furthermore, additional protection is required for multiphase
charging with smooth DC fault current. Either a type B RCD, an
RDC-DD (residual direct current detecting device) or an RCMB
(residual current monitoring module) can be used to this end.
Select Measuring Function
Set Parameter – Type RDC
Set Parameter – Time to Trip
Note
The RDC-DD is tested with nominal residual currents of 6
to 200 mA.
Start Measurement
System type:
I
N
I
F
or
Time to trip
6mA
60 mA
200 mA
10.0 s
0.3 s
0.1 s