ITT Lowara e-SV Series, Инструкция по установке и эксплуатации

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10. Troubleshooting
information for users and maintenance personnel
PROBLEM PROBABLE CAUSE POSSIBLE SOLUTION
The electric pump unit
does not start.
The main switch is on
No power supply Restore the power supply
Triggering of thermal protector incorporated in
the
pump (if any)
Wait for the pump motor to cool down
Triggering of thermal relay or motor protector
found
in the electric control panel
Reset the thermal protector
Pump or auxiliary circuits protection fuses blown Replace fuses
Triggering of protection device against dry
running
Check the water level in the tank or the mains
pressure. If everything is in order, check the
protection device and its connection cables
The electric pump unit
starts up but the thermal
protector is immediately
triggered or the fuses
blow
Power supply cable is damaged
Check the components and replace as necessary
Electric motor short circuit
Thermal protector or fuses not suited to the
motor current
Motor overload
Check the operating conditions of the electric pump
unit and reset the protection
The electric pump unit
starts up but, after a short
time,
the thermal
protector is triggered or
the fuses blow
A phase in the power supply is missing Check the power supply
Power supply voltage not within the motor’s
working limits Check the operating conditions of the electric pump
unit
The electric panel is situated in an excessively
heated area or is exposed to direct sunlight Protect the panel from heat sources and from the
sun
The electric pump unit
starts up but, after a
varying period of time,
the thermal protector is
triggered
There are foreign bodies inside the pump, the
impellers are jammed
Disassemble and clean the pump
The pump’s delivery rate is higher than the limit
specified on the rating plate
Partially close the on-off valve located downstream
until the delivery rate returns within the specified
limits
The pump is overloaded because it is sucking a
dense and viscous liquid
Check the actual power requirements based on the
characteristics of the pumped liquid, and replace
the motor accordingly
Worn motor bearings Replace the bearings or the motor
The electric pump unit
starts up but does not
deliver the required flow
Wrong rotation direction (three-phase version)
Check the direction of rotation and, if necessary,
exchange two phases in the motor or in the
electrical panel
Pump is not primed because not filled with water
Repeat the priming procedure and make sure there
are no leaks in the mechanical seal
Pump not primed due to tightness failure in
suction pipe or foot valve
Check the suction pipe and foot valve for perfect
tightness, make sure there are no leaks in the
mechanical seal
Air in the pipes or pump Bleed the air
Excessive suction lift or flow resistance in suction
piping
Check the operating conditions of the pump. If
necessary, decrease suction lift and/or increase the
diameter of the suction pipe
Piping or pump clogged Disassemble and clean
Valves locked in closed or partially closed
position Disassemble and clean, if necessary replace the
valve.
The system’s general
protection cuts in
Short circuit Check electrical system
The system’s differential
thermal-magnetic
protection cuts in
Ground leakage
Check insulation of the electrical system
components.
The pump rotates in the
wrong direction when it is
stopped Leaks in suction pipe Check and locate leaks
Repair or replace components.
Leaks in foot valve or check valve
Air in the suction pipe
Bleed the air
The pump starts up too
frequently
Leaks in foot valve, check valve or system
Check and locate leaks. Repair or replace the
components.
Ruptured membrane or no air pre-charge in
surge tank
See relevant instructions in surge tank manual
The pump vibrates and
generates
too much
noise
Pump cavitation
Reduce the required flow rate by partially closing
the on-off valve downstream from the pump. If the
problem persists check the operating conditions of
the pump (height difference, flow resistance, liquid
temperature,….)
Worn motor bearings Replace bearings or motor
Presence of foreign bodies inside the pump,
between the impellers and diffusers
Disassemble and clean the pump