GR-750x series
Control panel for addressable
emergency luminaires
Document number:
923750400_90_001_EN
Date: 25/5/2023
Page: 10 of 15
[10]
2.5 Wiring verification
IMPORTANT
The following steps should be performed while the cables are NOT
connected to the loop board terminals.
Steps to verify the integrity of the installation’s wiring:
1. Verify the mains power supply to the panel and the connection of the protective earth (
PE
) to the board
terminals. The panel should be supplied by a separate line with its own circuit-breaker.
2. Using a multimeter measure the resistance between the protective earth (
PE
) terminal and the panel’s
earth bar. It should be less than
10
Ω
.
Higher values indicate bad panel grounding, and it is
highly
dangerous and unsafe
to operate it.
3. Optical inspection of each cable for possible wear/damage caused during the installation.
4. Optical inspection of each point connection for bad/wrong wiring.
5. If points are connected using a loop topology, using a multimeter measure the resistance between each
L+
and its corresponding
LF+
line. It should be less than
60
Ω
. Higher values indicate faulty
connections/cable and should be investigated and resolved.
6. If points are connected using a loop topology, repeat the previous step for loop cable, each
L-
and its
corresponding
LF-
line and each shield line start-finish.
7. If points are not connected using a loop topology (no return line), connect temporally the
L-, L+
and its
shield
, at the last point (end of line) together. Using a multimeter measure the resistance between the
start of
L-
and
L+
line. It should be less than
60
Ω
. Higher values indicate bad connections/faulty cable
and should be investigated.
8. If points are
not
connected using a loop topology, repeat the previous step for the
L-
or
L+
line and its
shield
.
IMPORTANT
: Remove the temporal connection at the end of the line between
L-, L+
and its
shield.
9. Using a multimeter measure the resistance between each
L+
and its corresponding
L-
line. It should be
more than
10 k
Ω
. Lower values indicate faulty connections/cable/short circuits and should be
investigated and resolved.
10. Using a multimeter measure the resistance between each
L+
and its corresponding
shield
line. There
should be no circuit continuity (at least
10 M
Ω
)
. Lower values indicate faulty connections/cable/short
circuits and should be investigated and resolved.
11. Repeat the previous step between each
L-
and its corresponding
shield
line, each
L+
and the protective
earth (
PE)
line and each
L-
and the protective earth (
PE)
line.
12. Every time a problem is detected and corrected on a line, all the check for this line should be repeated
from the start.