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Operation
3. Preparation
■ Preparations for operation
1. Check the pump and pipework before operation.
a.
Check there are no foreign matters in the supply tank and pipework. If foreign matters are stuck in suc-
tion line, the pump may break. Do not leave any waste of bond, sealing materials and screws/nuts.
b.
Check pipework joints are tight enough so that air does not enter pipework. Take extra care to suction
line because the suction side is a vacuum.
c. Check the bolts on the pump unit and retighten them as necessary.
2. Follow the procedures below to start the pump at the first operation or after a long period of storage.
a. Detach the cap on the self-priming port. Fill the pump with liquid.
CAUTION
Do not pour liquid rapidly. Otherwise liquid may overflow.
b. Tighten the cap securely. Make sure air can not enter.
c.
Run the motor for a moment in order to check if the motor rotates according to the arrow label
*
1
(Clockwise, seen from the motor fan). If the motor rotates in reverse, interchange two of 3-phase power.
■
Precautions for starting/stopping the pump
(In case the pump is in flooded suction system.)
Follow the procedures below when starting/stopping the pump for the prevention of water hammer
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2
.
Take extra care when the discharge line is long.
a. When starting the pump
First, prime the pump. Then turn on power to start operation with a discharge valve fully closed.
And then gradually open the discharge valve and adjust flow rate to a specified point.
b. When stopping the pump
Gradually close a discharge valve. Turn off power and stop the pump after the valve is fully closed.
NOTE: When using a solenoid valve, set it to close slowly.
Word & Terms:
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1
An arrow label is placed on the upside of the motor fan cover.
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2
Shutting off the discharge line at once, liquid pressure change causes an impact pressure, accompanying impact
noise and vibration. This phenomenon is called water hammer. Water hammer damages the pump & pipework and
may cause leakage.