8.2 Soft starter
The starting voltage is min. 55 % of the value
stamped on the nameplate.
If a high locked-rotor torque is required or if the
power supply is not optimal, the starting voltage
should be higher.
Run-up time (until voltage stamped on
nameplate is reached): Max 3 sec.
Run-out time: Max 3 sec.
If the abovementioned run-up and run-out ramps
are followed, unnecessary heating of the motor
is avoided.
If the soft starter is fitted with bypass contacts,
the soft starter will only be in operation during
run-up and run-out.
The soft starter must not be used in connection
with operation via a generator.
Voltage
100 %
55%
0
3 sec.
Fig. 16
Operation with a soft starter
8.3 Maintenance and service
All pumps are easy to service.
Service kits and service tools are available from
Grundfos.
The pumps can be serviced at a Grundfos
service center.
Warning
If a pump has been used for a
liquid which is injurious to health
or toxic, the pump will be classified
as contaminated.
If Grundfos is requested to service the pump,
Grundfos must be contacted with details about
the pumped liquid, etc. before the pump is
returned for service. Otherwise Grundfos can
refuse to accept the pump for service.
Possible costs of returning the pump are paid by
the customer.
Time
3 sec.
9. Troubleshooting
The majority of problems that develop with
submersible pumps are electrical, and most of
these problems can be corrected without pulling
the pump from the well. The following chart
covers most of the submersible service work.
As with any troubleshooting procedure, start
with the simplest solution first; always make all
the above-ground checks before pulling the
pump from the well.
Usually only two instruments are needed:
•
a combination voltmeter/ammeter
•
an ohmmeter.
These are relatively inexpensive and can be
obtained from most water systems suppliers.
Warning
WHEN WORKING WITH
ELECTRICAL CIRCUITS, USE
CAUTION TO AVOID ELECTRIC
SHOCK.
It is recommended that rubber
gloves and boots be worn and that
care is taken to have metal control
boxes and motors grounded to
power supply ground or steel drop
pipe or casing extending into the
well.
Warning
Submersible motors are intended
for operation in a well. When not
operated in a well, failure to
connect motor frame to power
supply ground may result in
serious electric shock.
17