Rotating in reverse direction
Rotating in reverse direction
(OP)
Assuming that the pump is OFF, and the check valve is leaking and the water is comming baack to the pump causing a reverse rotation. what is the bad effect of this rotation if the pump is OFF, and no one run the pump during the reverse rotation.
Thanks for your input
Thanks for your input





RE: Rotating in reverse direction
RE: Rotating in reverse direction
RE: Rotating in reverse direction
If the pump is the "lead pump" and starts periodically, when the moment arrives for returning to work, suddenly the abnormal rotation will be inverted (to the normal one) and it is here when, with this repetitive action that the mechanical seal of the pump begins to be damaged.
I have experienced a lot of these problems with submersible pumps and, the remedy has been to solve properly the leakage through the check valve.
Another associated problem with the leakage in the check valve is the risk that the pump starts with a voided discharge pipe and, you will have to add to your problems the consequences that this involves.
RE: Rotating in reverse direction
As long as the motor is guaranteed to remain OFF, those might be manageable risks. But what happens when you need to start the pump to put the fluid back where it was? Is there a means provided to stop the reverse rotation? Will everyone bother, all the time?
Starting a motor that's already running backwards is pretty much guaranteed to cause severe electrical problems.
By way of illustration, I have one data point: "Plugging" a small 1/15HP 115VAC PSC motor will blow a 20A breaker right out of the panel. I don't know if the breaker exploded before launch, or on impact with the floor. It made a surprising amount of noise.
Mike Halloran
Pembroke Pines, FL, USA
RE: Rotating in reverse direction
Johnny Pellin
RE: Rotating in reverse direction
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Sometimes I only open my mouth to swap feet...
RE: Rotating in reverse direction
A.
RE: Rotating in reverse direction
This could cause the pump to run at or through a rotor resonant frequency. This in turn could result in damage to the rotating element.
One other consideration that has not been mentioned is that some bearing lubrication systems do not function correctly in reverse. This can be checked with the manufacturer.
RE: Rotating in reverse direction
RE: Rotating in reverse direction
Please post this as a new question. You will get better responses that way.
Thanks
Patricia Lougheed
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