Wilo Actun FIRST SPU 4 Instrucciones De Instalación Y Funcionamiento página 19

TROUBLESHOOTING AND RECTIFICATION
Generally, motor protection relays, overvoltage
relays and other triggers can be manually trig-
gered for test purposes.
9 Troubleshooting and rectification
In order to prevent damage to property and
serious injury when repairing faults on the unit,
observe the following:
• Only attempt to remedy a fault if you have
qualified staff, meaning that each job must be
carried out by trained specialist personnel. Elec-
trical work, for example, must be performed by a
trained electrician.
• Always secure the unit against an accidental
restart by disconnecting it from the mains. Take
appropriate safety precautions.
• Always have a second person on hand to ensure
the unit is switched off in an emergency.
• Secure moving parts to prevent injury.
• Unsanctioned modifications to the unit are made
at the operator's own risk and release the manu-
facturer from any warranty obligations!
DANGER due to electrical current!
Electrical current can cause fatal injuries if not
dealt with correctly! If this error is displayed,
the connection must be checked and repaired
by a qualified electrician.
9.1 Faults
9.1.1 Fault: The unit will not start
1. Electrical supply interrupted, short-circuit or
earth fault in the cable and/or motor winding
• Have the motor and wires checked by a specialist
and replaced if necessary
2. Tripping of fuses, motor protection switch and/or
monitoring devices
• Have a specialist inspect the connections and
modify them as necessary
• Fit or adjust the motor protection switches and
fuses according to the technical specifications,
and reset monitoring devices
• Check that the impeller turns freely. If necessary
clean it and free it up
9.1.2 Fault: The unit starts, but the motor protection
switch triggers shortly after commissioning
1. The thermal trip on the motor protection switch is
incorrectly selected and set
• Have a specialist compare the chosen trip and
setting with the technical specifications and
correct it as necessary
2. Increased current consumption due to major
voltage drop
• Have an electrician check the voltage on each
phase and rewire if necessary
3. 2-phase operation
• Have a specialist inspect the connection and
correct it as necessary
4. Excessive voltage differences between
the 3 phases
Installation and operating instructions Wilo-Actun FIRST SPU 4
• Have a specialist inspect the connection and
switching system and correct it as necessary
5. Incorrect direction of rotation
• Swap the 2 phases of the mains supply
6. Impeller slowed by accumulation, clogging and/or
solid matter, increased current consumption
• Switch off the unit, secure it against being
switched back on again, free the impeller and
clean the suction port
7. Fluid density is too high
• Contact the manufacturer
9.1.3 Fault: Unit is running but not pumping
1. No fluid present
• Open inlet for tank or slide valve
2. Inlet blocked
• Clean the supply line, slide valve, suction piece,
suction port or suction strainer
3. Impeller blocked or braked
• Switch off the unit, secure it against being
switched back on again and free the impeller
4. Faulty hose/piping
• Replace defective parts
5. Intermittent operation (cycling)
• Check switching system
9.1.4 Fault: The unit runs, but does not comply to the
specified operating values
1. Inlet blocked
• Clean the supply line, slide valve, suction piece,
suction port or suction strainer
2. Slide valve closed in the pressure pipe
• Open the slide valve if necessary and constantly
monitor the current consumption
3. Impeller blocked or braked
• Switch off the unit, secure it against being
switched back on again and free the impeller
• Incorrect direction of rotation
• Replace 2 phases of the mains supply
4. Air in the system
• Check the piping, pressure shroud and/or hydrau-
lics, and vent if necessary
5. Unit pumping against excessive pressure
• Check the slide valve in the pressure pipe and
open it completely if necessary, use a different
impeller, consult the plant
6. Signs of wear
• Replace worn parts
• Check fluid for solids
7. Faulty hose/piping
• Replace defective parts
8. Impermissible gas content in the fluid
• Consult the plant
9. 2-phase operation
• Have a specialist inspect the connection and
correct it as necessary
10. Excessive decrease in the water table during
operation
• Check the supply and capacity of the system, and
inspect the level control settings and function
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