Endress+Hauser Liquiphant M FTL51C - Trouble-Shooting; Recherche de Défauts

56 Endress+ Hauser
en - Trouble-shooting
Fault Reason Remedy
Does not switch No power Check power
Faulty signal line Check signal line
F aulty electronic insert
- FEL51 connected directly to L1 and N
Exchange
- always connect FEL51 via external load
Density of liquid too low Set density to > 0.5 at electronic insert
Fork encrusted Clean fork
Fork corroded
(Indication on FEL: red/yellow flashes,
FEL58: green flashes 0.3 Hz)
Exchange fork and process connection
FEL51: Internal resistance of connected
relay too large
Connect suitable relay
FEL51: Holding current of connected relay
too low
Connected resistor in parallel with relay
FEL54: Contacts welded together
(after short-circuit)
Exchange FEL54;
put fuse in contact circuit
Switches
incorrectly
Min-/Max- fail-safe mode set wrongly Set correct mode at electronic insert
Sporadic faulty
switching
Thick heavy foam,
very turbulent conditions,
foaming liquid
Mount Liquiphant in bypass
Extreme RFI Use screened cable
Extreme vibration Decouple, damp, turn fork 90°
Water in housing Screw cover and cable gland tight
FEL52: Output overloaded Reduce load,(cable) capacitance
Switches
incorrectly after
power failure
FEL57, behaviour during switch-on test
(functional test)
Observe switching behaviour of FEL57;
After power failure block plant control
for up to 45 s