Flowserve NRS1-41 - Manual (Page 17)

17
System Malfunctions
– continued –
LED 3 flashes slowly.
A communication malfunction in the
bus line was detected.
System Malfunction 2
LED 3 flashes slowly
LED 1 flashes slowly Hold down button .
LED 1 flashes slowly.
A communication malfunction in the bus
line between level switch and level
electrode was detected.
Fault: The data transfer between level switch and electrode is interrupted.
Remedy: Make sure that the bus lines are all wired in accordance with the wiring
diagram (observe polarity). All end-of-line devices must be provided
with a terminating resistor of 120
Ω
(see wiring diagram).
Cut off power supply and restart system after 5 sec.
Fault: The baud rate of one or more bus devices is not set correctly.
Remedy: Check baud rate settings of all bus devices. The baud rate settings must
be identical. Please refer to section “Annex”.
Cut off power supply and restart system after 5 sec.
Fault: The overall length of the bus line does not correspond to the baud rate
setting.
Remedy: Change baud rate settings of all bus based equipment as described
under “Annex”.
Cut off power supply and restart system after 5 sec.
Fault: In spite of correct wiring and commissioning of the equipment an
interference signal is indicated.
Remedy: The interference signal is caused by H. F. interferences coming from the
installation. For interference suppression of the voltage supply we supply
ferrite rings, stock code 147253. The 230 V supply lines should be
looped through the ferrite ring five to ten times. If several controllers are
used in the system, they can be fed from the interference suppressed
supply lines. For the interference suppression of the bus line we supply
hinged-shell ferrite rings, stock code 147254. The hinged-shell ferrite
rings are clamped onto the bus line close to the terminal strip of the
controller.
Restart the system after installation.