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Swinging of Amp meter??

Swinging of Amp meter??

Swinging of Amp meter??

We have here in the refinery two pumps working parralel.
On the one pump the amp meter is swinging between 50-70A and at the other ampmeter is steady at 100A.
The pump that is swinging is making a funny sound like going up and then down.

What is the best practice to stop this?

I'm thinking of pinching the discharge valve at the swinging pump or open the discharge valve at the steady pump and see if they will steady out!!!

any comment will be appreciated.

RE: Swinging of Amp meter??

Two reasons for this.

1. Improper suction (pump is starving)
2. Entrapped air in the system.

Try to control discharge of the pump running at full load(100A)instead and do the venting.


RE: Swinging of Amp meter??

To back up quark's comments (I'm assuming these are typical centrifugal pumps), it appears that the second pump is doing all the work (pulling 100A) while the first is pumping air or is cavitating... [Is the first pump worn out?] -- by pincing down the discharge of the second pump, it should allow the first pump to pump more fluid thus evening out the amp loadings...

RE: Swinging of Amp meter??

on thinking about your posting, i wonder if these pumps are identical, how the piping system is piped, what mechanism are used to control flow or pressure, etc.

for the pump drawing 100 amps, you "imply" that the discharge valve is partially closed and the other pump's (drawing 50-70 amps) discharge valve is fully open.  this is what is not clear or can be confusing.

while the two previous postings provide useful tips, please clarify/advise pump type; are pumps identical (i.e. impeller diameters), current status of valve positions, and perhaps a brief description of piping arrangement.  i request the latter as too often, i've seen pumps in parallel arrangement that will have significantly different flow rates because of unequal resistance (i.e. flow paths) between the common inlet & outlet piping.

good luck!

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