GESTRA NRS 1-41, Original Installation Instructions

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Operational Malfunctions
Fault finding list for troubleshooting
Switchpoint HW exceeded – control unit does not respond
Fault: LED “Power” is not illuminated.
Remedy: Apply mains voltage. Wire equipment according to the wiring diagram.
If faults occur that are not listed above or cannot be corrected, please contact our service centre or
authorized agency in your country.
Level has not yet reached switchpoint HW – control unit raises HW alarm
Fault: The isolating valves of the external measuring pot (optional) are closed.
Remedy: Open isolating valves.
Fault: The vent hole in the protection tube is flooded.
Remedy: Check protection tube.
Danger
The terminal strips of the equipment are live during operation.
This presents risk of severe cases of electric shock!
Cut off power supply to the equipment before mounting or removing the terminal strips or
the housing cover!
Equipment does not work – malfunction message in control unit
Fault:
In spite of correct wiring and commissioning of the equipment an error message is
indicated.
Remedy: Cut off power supply to the equipment. Remove terminal strips and reattach them.
Restart system after 5 sec.
Remedy: Carry out systematic fault finding as described in chapter “System Malfunctions” .
Fault: No HW alarm is raised although the electrode is submerged.
Remedy: The conductivity of the fluid to be monitored is below 0.5 μS/cm.
Increase the conductivity of the fluid.
Electrode submerged – no HW alarm
Fault: The electrode body does not have earth connection to the vessel.
Remedy:
Clean seating surfaces and insert metal joint ring (of stainless steel 1.4301)
D 27 x 32 to DIN 7603.
Do
not insulate electrode with hemp or PTFE tape!