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IOM Manual: IOM-0000-CST IOM
Series CST: Submersible Turbine
01/01/2018 - Edition 1A
www.cps-pumps.com
PROVIDING A PROPER POWER
SUPPLY
The power supply must have an adequate capacity (KVA) and
must be of the proper voltage, phase and frequency to match
the motor requirements. Three phase systems should have a full
three phase supply utilizing three individual transformers or one
three phase transformer. Open delta or wye systems using only
two transformers must be de-rated. Such installations are also
more likely to suffer from phase unbalance problems. Unbal-
anced voltage on three phase power sources will cause unbal-
anced motor currents. Motor current unbalances in excess of
5% can be expected to cause excessive heating in the motor, re-
sulting in poor motor performance, nuisance overload tripping,
and premature failure of the motor. If the power company can-
not guarantee less than 5 percent unbalance, the use of the next
larger size motor and the next larger size cable is recommended.
Contact CPS-Pumps for further information. The warranty can
be voided by the use of an improper power supply.
SELECTING AND INSTALLING A
PROPER MOTOR CONTROL SYS-
TEM
The motor control system must be sized to accommodate the
pump motor. The control system should protect the motor
from damage from abnormal conditions such as low voltage,
high voltage, overload, excessive current unbalance, phase loss,
overheating, lightening, etc. Single phase 3-wire motors require
a special submersible motor control box. A standard magnetic
starter with special extra-quick overload relays can be used
for three phase motors; however, a control which is designed
specially for submersible pumps is recommended. Overload
protection and fuse requirements are given in the pump motor
manual. The warranty can be voided by the use of an improper
control system.
SELECTING THE PROPER DROP
CABLE
Submersible pump drop cable is a special waterproof, heavily in-
sulated cable made especially for this use. The cable size is based
on the motor horsepower and voltage, and the distance from the
motor to the control panel. Cable size selection charts are given
in the motor manual. Failure to use the proper size and type
cable can void the warranty.
MAKING THE SPLICE BETWEEN
THE MOTOR LEADS AND THE
DROP CABLE
A water-tight splice must be made to connect the drop cable to
the motor leads. See PRE-INSTALLATION MOTOR AND
DROP CABLE CHECKS AND PREPARATION on page
10.
PROPERLY GROUNDING THE
UNIT
All units must be grounded in accordance with applicable codes.
Failure to ground the unit properly can result in serious or fatal
shock.
MAKING AND EVALUATING ELECTRICAL TESTS.
Installation, troubleshooting, and maintenance of a submers-
ible pump will require performing and evaluating electrical tests
such as resistance, continuity, voltage, current, current unbal-
ance, etc. Some of these tests are described in ELECTRICAL
TESTS on page 18. The use of electrical testing as a trouble-
shooting tool can very often quickly identify the problem and
prevent the unnecessary time and expense of pulling the pump.
SELECTING AND INSTALLING
AUXILIARY EQUIPMENT
A low water level switch is recommended and can be supplied
as an option from CPS-Pumps. The installation will also most
likely require auxiliary equipment such as flow switches, pres-
sure switches, level switches, time switches, etc. The need for
this equipment must be evaluated based on the requirements
of each installation and the proper equipment must be selected
and installed.
Since most submersible pump service problems are electri-
cal, it is imperative that the electrical work be done properly
using high quality materials if the pump is to provide the long,
trouble-free life for which it is designed.
