The pump set must not remain idle for more than a week since it might lead to jamming of rotating parts. If the pump set is to remain idle for longer periods, it is to be run at least once every week for five minutes. This will ensure that the pump set is ready for service at any desired time.

How should the operation at shut-off be?

The pump set must not be run more than five minutes at zero discharge, since the pump will get over heated due to churning of water in the pump. If a low discharge is required at least 10% of the maximum discharge must be allowed.

What is the ideal switching frequency?

The stand-still time of the pump between switching off and switching on again should be at least five minutes.