9.2 Assembling the pump / motor group
–
Check the free rotation of pump and motor
rotating parts, paying attention not to damage
them.
–
The axial joint between pump shaft and motor
shaft
should
be
Absolutely avoid kicking the shaft, as that could
damage the thrust bearing.
–
The pump-motor coupling should be done
perfectly, a wrong alignment will unavoidably
cause motor bearing failure and vibrations.
–
The pump joints are provided with screws to lock
the rotating part axially.
The coupling screw for 10" - 12" - 14" motors
should be strongly locked on the motor key.
–
When coupling 6" - 8" motors, the coupling screw
shall be aligned to the hole located on the motor
shaft; after locking, the screw must be unscrewed
half turn and locked in this position by a sealing
product (loctite or similar) or in a mechanical
11. TROUBLESHOOTING
FAULTS
1.
The pumps gives no water.
2.
The pump is not starting but
fuses don't blow up and
starter relays do not trip.
3.
The starter trips or the fuses
blow-out when the pump is
running.
installed
without
forcing.
Error conditions
CHECKS
(possible causes)
A. Water level in the well lower than
pump suction nozzle.
B. Blocked valve.
C. Leaks in the delivery pipe.
D. Voltage lower than the rated value
and absorption higher than normal.
E. Absorbed current lower than normal
due to air in the pump.
F. Clogged grid because of suspended
solids.
G. Unexpected fiction losses
A. No voltage in the line.
B. The circuits is cut off by the cable on
in motor windin.
C. Open circuit in the starter.
A. Too low voltage.
B. Overload due to sand clogging;
bearings tend to saize.
C. Single phase: a voltage 1.5/2 times
higher than normal runs through
motor windings, so the starter trips
stopping the unit.
D. The starter is installed in a too warm
place.
E. The
starter
ENGLISH
position positive way (calking), paying attention
not to damage the screw thread. The locking of
the screw on the shaft could cause an
eccentrical rotation of the rotating part and
consequently damage the bearings.
10. DECOMMISSIONING AND
DISMANTLEMENT
When the pump will be permanently stopped and
dismantled, the various materials composing it should
be properly disposed of. It is important to make sure
that no residual polluting liquids are trapped within the
pump.
The materials used in pump construction are:
-
Steel and cast iron.
-
Aluminum.
-
Rubber and plastic.
-
Copper.
The disposal of polluting liquids and materials should
follow current environmental regulations.
in
not
correctly
23
REMEDIES
A. Increase the pump depth.
B. Kick the pipe line with a hammer
trying to unblock the valve.
C. Check delivery pipe by the flanges.
D. Increase voltage.
Change the supply cable with a
larger one.
E. Start and stop the pump at intervals
of about a minute.
F. Clean the pump.
G. Check calculations and use larger
pipes if necessary.
A. Check voltage ratings on main and
on starter terminals.
B. Remove starter fuses and connect
one Ohmmeter conductor to delivery
pipe; Check then motor cables
terminals one by one with the other
conductor. The reading of each
terminal shloud be at least 10
Megahoms.
C. Check circuit integry referring to
electric diagrams.
A. Increase supply cable diameter.
B. Pull on the pump and clean it.
C. Check voltage on all three phases.
Check the conditions of starter fuses
and contact.
D. Set starter overload relays on the
highest value.
E. If the amperometer shows normal