33
System Malfunctions
Faulty installation and/or configuration of CAN bus components, excessive temperatures in the devices,
defective electronic component parts or electromagnetic interferences of the supply system can result
in system malfunctions. In the event of a system malfunction the safety circuit (terminal 25 and 29) is
instantly interrupted.
There are four system malfunctions that might occur in the level electrode and the switching controller.
n
Max. admissible temperature in electrode terminal box exceeded
n
No or faulty communication between controller and electrode
n
Fault in CAN bus
n
Failure of 24 V power supply unit built in switching controller NRS 240
The automatic selftesting routine checks the switching controller every 3 seconds and the sensors
(e.g. the level electrodes) every 10 seconds. During each selftesting routine the error messages will
be stored in the switching controller. The error messages remain stored until the cause of the fault(s) is
eliminated. If a malfunction is detected the signal output of the switching controller (terminals 7
and 8) will be opened and closed as a function of the triggering pulse. As part of the automatic self
testing routine the function of the output relays will also be checked every 6 hours.
The terminal strip of the equipment is live during operation.
This presents the danger of electric shock.
Cut off power supply before mounting or removing the terminal strips or the housing
cover.
Danger
NRS 2-40