-12-
Prior to Operation
(1) Once again, check the nameplate of the pump to verify that its voltage and frequency are correct.
Improper voltage and frequency of the power supply will prevent the pump
from attaining its full potential, and may also damage the pump.
Verify the specs on the pump's nameplate.
(2) Check the wiring, power supply voltage, the capacity of the ground leakage circuit breaker, and the
insulation resistance of the motor.
Insulation resistance reference value = 20MΩ minimum
The insulation resistance reference value of 20MΩ minimum is based on a new or repaired pump. For refer-
ence values of a pump that has already been put into operation, refer to "Maintenance and Inspection".
(3) Adjust the setting of the thermal relay (i.e. 3E relay) to the pump's rated current.
Verify the rated current on the pump's nameplate.
CAUTION
Note:
Note:
Note:
Trial Operation
Never start the pump while it is suspended, as the pump may jerk and cause
a serious accident involving injury.
(1) Operate the pump for a short time (1 to 2 seconds) and verify the direction of the rotation of the impeller.
Observe the pump unit from above, and if its recoil is in the counterclockwise direction, the direction of
its rotation is correct.
Make sure to check the pump's direction of rotation with the pump exposed
to the atmosphere. Operating the pump in reverse while it is submerged in
water will damage the pump, which may lead to current leakage and electrical
shock.
(2) To reverse the rotation, the following countermeasures must be taken.
WARNING
CAUTION
Before changing the connections for reverse
rotation, make sure that the power supply
(i.e. circuit breaker) is properly disconnected
and that the impeller has stopped
completely. Failure to observe this may lead
to electrical shock, short, or injury.
COUNTERMEASURE
Direct-on-line starting
Interchange any two of the three wires designated U, V, and W,
respectively.
WARNING
6-1 NON-AUTOMATIC OPERATION
COUNTERMEASURE
Star Delta startingInterchange any two of the three phases
designated R, S, and T, respectively.
This method cannot be used if the starting panel is equipped
with a reverse-phase detector such as a 3E relay. If this is the
case, contact the manufacturer of the starting panel, the dealer
where the pump was purchased, or the Tsurumi sales off ce in
your area.
Note:
6 OPERATION
Example:
U
V
W
G
Interchanging
phases V and W
Ground
R S T
(Example)
Interchanging phases S and T
