GESTRA NRS 1-41, Original Installation Instructions

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31
System Malfunctions
– continued –
Error message 2
LED 3 flashes slowly.
A communication malfunction in the bus line
between the control unit and
level electrode
was detected.
Hold down button .
LED 1 flashes slowly.
Fault: The bus lines C
L
and C
H
have been mixed up.
Remedy: Wire bus line in accordance with wiring diagram.
Fault The data transfer between control unit 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.
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.
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 inter
ference 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.
A