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Emergency Operation
Emergency operation of water level limiting system LW
Provided that the control unit works with two level electrodes NRG 1x-40 (water level limiting system), if
one level electrode fails to operate the installation can continue to operate in emergency mode with
one
level electrode under constant supervision according to TRD 401 and EN 12952 and EN 12953.
The following settings are required:
1. Set the wire link to the left in order to configure the working level electrode as device 1 and set the
node ID to “2” (see
“Emergency Operation”
in the installation manual of NRG 1x-40).
2.
Control unit: Cut off power supply
and unplug the lower terminal strip
B
.
3. The terminal strip can be unplugged after undoing the right and the left fixing screws
C
.
4. Set switch S1 of the code switch
D
Fig. 4
to ON and S2 to S7 to
OFF
. The control unit NRS 1-40.1
has now the node ID 1.
5. Set switches S1 and S2 of the code switch
E
Fig. 4
to
OFF
.
6. Re-insert terminal strip
B
and fasten the fixing screws
C
.
Attention
n
Enter beginning of emergency operation in the boiler log.
n
An installation operating in emergency mode has to be constantly supervised!
n
Immediately replace faulty level electrode.
n
Enter end of emergency operation in the boiler log.
