6
GMC-I Messtechnik GmbH
Simulation of “Interference Voltage in the Protec-
tive Conductor” with Probe
In the case of type S PRCDs (PRCD-S), the
on/off key is made of a conductive material
or coated with conductive plastic so that the
sensor inside the device is capable of
detecting dangerous contact voltage at the
protective conductor terminal of the electri-
cal power connection in the form of a differ-
ence in potential relative to the user’s con-
tacting finger.
During simulation of the “interference voltage
in the protective conductor” fault (tripping
test / potential fault as extended function
test for PRCD-S) by touching the on/off key
of the single-phase PRCD (PRCD-S) with
the probe, a difference in potential between
the contactable sensor surface and the pro-
tective conductor terminal is generated
which causes tripping of the PRCD-S.
The probe socket on the PRCD adapter is
connected to the phase conductor (L) of the
power supply network via a series resistor
(safety impedance) with a value of 1 M
Ω
using the test adapter’s earthing contact
plug to this end.
Touch current at the probe socket is limited
by the internal protective circuit to less than
the maximum permissible value of 0.5 mA in
accordance with DIN EN 61010-1.
Execution of this test results in maximum
touch current of:
Measuring Protective Conductor Current
Protective conductor current or bias current
may result in premature tripping of PRCDs.
For this reason, the protective conductor is
led out of the housing as a loop between
surface mount sockets 4 and 6. This makes
it possible to measure any protective con-
ductor current with the help of a current
clamp transformer.
3
Initial Start-Up
See the connections overview on page 2 for
all connection variants.
3.1
Testing the LEDs
Before performing any measurements, the
LEDs should be tested for correct function-
ing.
Single-Phase Mains Connection
➭
Insert the earthing contact plug into the
earthing contact mains outlet, remove it,
rotate it 180° and insert it again.
When connected with correct polarity, the
PRCD IN L1
LED must light up, and when
rotated 180° the
PRCD IN
L1
and
PRCD IN PE
LEDs must light up simultaneously.
3-Phase Mains Connection
➭
Insert the CEE plug into the CEE outlet.
The
PRCD IN L1
,
L2
and
L3
LEDs must light
up. If any of the phase conductors are con-
nected to the neutral conductor, i.e. L1-N,
L2-N or L3-N, N lights up instead Lx. If any
of the phase conductors are connected to
protective earth, i.e. L1-PE, L2-PE or L3-PE,
PE lights up instead of Lx.
3.2
Mains Connection
The test adapter must be connected to the
mains for fault simulation, as well as for indi-
cation by means of the phase LEDs.
➭
Connect the test adapter to the mains
via the single or 3-phase mains power
cable. Refer to the characteristic values
on page 14 for nominal mains values.
Attention!
!
Single-Phase Mains Connection
For correct phase connection, the
earthing contact plug must inserted
into the mains outlet such that only
the
PRCD IN L1
LED lights up.
The
PRCD IN
PE LED lights up as well
in the case of polarity reversal.
I
T
[A] =
U
Mains (L–PE)
[V]
1 M
Ω
PROFI
TEST
⏐
P
RCD
Initial Start-Up