GESTRA NRS 1-8, Руководство по установке

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17
Operational malfunctions
Fault finding list for troubleshooting
Level electrode exposed - High-level alarm
Fault:
The level switch raises a high-level alarm before the level in the boiler has reached
the high-level mark.
Remedy: Check length of high-level electrode tip. Make sure that the level switch and the
electrode are wired in accordance with the wiring diagram.
Fault: After lowering the water level below the high-level mark, the two red LEDs 0 are
still illuminated or go out only after quite some time.
Remedy: Check whether the protection tube is provided with a vent hole.
If the electrode is fitted in a measuring pot outside the boiler, check positions
of isolating valves.
Fault: One or both LEDs
0
light up without the water level having reached the high-level
mark.
Remedy:
This means loss of redundancy in the level switch, i. e. failure of one or two of the
channels. Replace level switch.
High water level reached - no function
Fault: The water level exceeds the high-level mark but neither of the two red LEDs 0
lights up.
Remedy:
Check whether the protection tube is provided with a vent hole.
If the electrode is fitted in a measuring pot outside the boiler, check positions
of isolating valves. Measure the conductivity of the boiler water and compare the
value obtained with the specification on the name plate.
Fault: The test “TEST 2 / INSPECTION”
9
was not successful, i. e. only one red LED 0 or
none of the two lit up after max. two minutes .
Remedy:
Replace level switch.
Operation
Use in conjunction with level switch NRG 1...-12 in steam and pressurised hot water plants in accord-
ance with TRD 401, TRD 602, TRD 604, EN 12952, EN 12953 or according to other national regulations.
Water level limiter
Notice
n
To analyse and eliminate malfunctions refer to section
“Fault finding list for troubleshooting” on pages 17 – 18.