SBI/SBN Vertical Multistage Centrifugal Pumps
6
8. Maintenance
WARNING:
Before starting maintenance work on the pump, the motor, or other parts of the system, make sure that the power supply has
been switched off.
— The pump does not have a recommended maintenance schedule.
— If the motor is fitted with grease nipples, then the motor should be lubricated with a high temperature lithium-based
grease. If not, then the motor does not require regular maintenance.
— If the pump and motor are used infrequently with long intervals of non-operation, then we recommend that the
motor be greased.
— Coupling adjustment: Refer to page 8 and 9.
9. Troubleshooting
Fault
Probable cause
Possible Solution
a. Supply failure or no power supply.
Check connections or restart the power supply.
b. Main contacts in motor starter are not making
Reconnect or replace contacts or magnetic coil.
Pump does not run
contact or the motor coils are defective
when the motor
c. Pump or auxiliary circuits protection fuses blown.
Replace fuses.
starter is activated.
d. Pump or piping system may be obstructed causing a jam.
Clean the obstruction and restart pump.
e. Motor may have failed.
Replace the motor.
f. Motor protector or thermal relay has tripped out.
Reset the motor or thermal protector.
g. Tripping of dry running protection.
Check the water level in the tank or the water
system pressure. If everything is in order, check
the protection device and its connection cables.
a. Overload setting is too low.
Set the motor starter correctly.
Starter overload
b. The cable connection is loose or faulty.
Fasten or replace the cable connection.
trips immediately
c. One fuse is blown.
Replace fuse and try starting again.
when the power
d. Pump is jammed by an obstruction
Check and clean obstruction from system.
is switched on.
e. Contacts in overload are faulty.
Replace motor starter contacts.
f. The motor winding is defective.
Replace the motor.
g. Low voltage (Especially at peak time).
Check the power supply.
The pump starts
a. The voltage is not within the motor’s operating limits.
Check the operating conditions of the pump.
but, after a short
b. The control panel is situated in an excessively heated
Protect the control panel from heat sources and
time, the thermal
area or is exposed to direct sunlight
from the sun.
protector trips out
c. A phase in the power supply is missing.
Check the power supply.
or the fuses blow.
a. Worn motor bearings causing motor to overheat.
Replace motor bearings.
The pump starts
b. The Pump’s delivery rate is higher than the specified rate
Partially close the on-off valve on the discharge
but, after a period
on the pump nameplate.
side of the pump until the delivery rate is within
of time, the thermal
the specified limits.
protector trips
c. There are obstructions inside the pump or pumping system.
Disassemble and clean the pump and piping.
d. More viscous liquids may cause the pump to overload the
Check the actual power requirements based on
motor, causing the motor to overheat.
the characteristics of the liquid being pumped,
replace the motor accordingly.
a. Pump is not primed with liquid.
Fill the pump with the liquid to be pumped.
b. The pump, suction or discharge pipes are blocked by
Clean the pump, suction or discharge pipe.
Pump runs but
solids in the liquid being pumped.
no water is
c. The foot or check valve is blocked or has failed.
Replace the foot or check valve.
delivered
d. The suction pipe leaks.
Repair or replace the suction pipe.
e. Air in the suction pipe or pump.
Remove trapped air from system..
f. Motor operating in wrong direction (three-phase motor).
Change the direction of rotation of the motor
by reversing motor connections.
The pump capacity
a. The pump draws in air or the inlet pressure is too low.
Improve the suction conditions.
is not constant.
b. The pump or the suction side of the piping system
Clean the pump or suction pipe.
partly blocked by foreign bodies.
The system's general
Short circuit.
Check electrical system.
protection cuts in.
The pump rotates in
a> The foot or the check valve has failed.
Check and replace check valve.
the wrong direction
b> Leakage in the suction pipe.
Repair or replace the suction pipe.
when switched off.
