Fail-Safe Mode; Lower Switch Point; Maximum Fail-Safe Mode; Operation - Endress+Hauser nivotester FTC 422 Montage- Und Betriebsanleitung

Operation

The relay de-energises when the product rises above the upper
switch point: the red LED lights and remains lit until the product
drops below the lower switch point.
Level
Relay
status
On power failure both green and red LEDs extinguish: the relay
de-energises.
LED
status
Level: rising
Relay: energised
Red LED: off
Level: >Max
Relay:de-energised
Red LED: lit
Level: falling again
Relay:de-energised
Red LED: lit
Level: <Min
Relay:energised
Red LED: off

Power failure

Relay: de-energised
both LEDs: off

Maximum fail-safe mode:

Fig. 10
Operational sequence for maximum

fail-safe mode

Power failure
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