11
OPERATION
Warning
・
During the operation, verify no liquid leaks, the noise of the pump and motor and the drainage state of
the liquid.
If the abnormal state is found, stop the pump immediately and take measures.
・
When blackout or the electric power failure, turn off the switch. After recovery of the power, each
pump should start one by one.
The minimum liquid level during the operation
Keep the liquid level which the whole of the pump is sunk in.
(The minimum liquid level at the continuous operation: 400mm (15.7in) and more from the mounting
surface of the pump)
The continuous operation below the minimum liquid level should work 5 minutes or less. Also do not
operate the pump at short intervals.
According to the operation condition, the built-in thermal protector is activated and the pump
could stop. At such times, the operation should be paused and verify the pump without the
abnormal condition. After securing the proper liquid level, operate the pump.
The minimum liquid level at the start of the pump is 100mm (4in) and more.
Based on the condition of the liquid surface, even if the liquid level is over the available
operational liquid level, air enters the pump and the operation could be impossible.
When operating the pump in the air, the rotation parts inside of the pump could be damaged.
Measures against air lock
If the liquid stands in the drain pipe when stopping the pump, air lock could happen at the re-start of
the operation and water priming could be inefficient. Additionally, the same phenomenon easily
happens after
deadhead running. In this case, install the air release valve in the drain pipe, or make
sure the air release and prime the liquid in the pump casing before the operation.
When installing check valves between the suction piping, install exhaust bypass pipes at the bottom.
(No air release pipe may cause air lock.)
