I have a three phase water pump motor in a well that has not been used for some time. Long story don't ask. When it was put in the well the individual that installed it had a problem in that it was not pumping near the capacity that it should. He made a call to his boss and was told how to fix the issue which it did. I believe he swapped two wires but do not know which ones. The wiring was left "as is" bare end after he disconnected from the 3 phase power and left.
I am getting ready to use the well/pump with 3-phase power. The wiring that comes up from the well is the standard red, black, yellow, green. Interestingly the green wire end is not stripped so he never used it initially, so obviously no ground assuming it is wired normally but I have no reason to believe that the installer wired correctly as he was not the sharpest tool in the shed.
I am not a 3-phase motor expert but my understanding is a 3-phase motor that runs backward can be reversed by switching any two of the three hot wires. (on line research) I do not know this as fact however. Since I am certain he fixed his issue of low pump flow by reversing wires this implies that the well pump was running backward and thus pumping at a low rate. The pump is a relatively high flow pump 50+ gpm.
Will a well pump work, just low flow if running backward? Seems counter-intuitive to me.
Is it true that a 3 phase motor will run backward if wired incorrectly and can be "fixed" by reversing two wires?
Since I am getting ready to wire it up and I have no faith that the wire color coding is to standard I want to figure out what to do if the standard coding doesn't work for running the pump properly.
Hope a well pump installer is on the forum or a motor/pump expert.
I am getting ready to use the well/pump with 3-phase power. The wiring that comes up from the well is the standard red, black, yellow, green. Interestingly the green wire end is not stripped so he never used it initially, so obviously no ground assuming it is wired normally but I have no reason to believe that the installer wired correctly as he was not the sharpest tool in the shed.
I am not a 3-phase motor expert but my understanding is a 3-phase motor that runs backward can be reversed by switching any two of the three hot wires. (on line research) I do not know this as fact however. Since I am certain he fixed his issue of low pump flow by reversing wires this implies that the well pump was running backward and thus pumping at a low rate. The pump is a relatively high flow pump 50+ gpm.
Will a well pump work, just low flow if running backward? Seems counter-intuitive to me.
Is it true that a 3 phase motor will run backward if wired incorrectly and can be "fixed" by reversing two wires?
Since I am getting ready to wire it up and I have no faith that the wire color coding is to standard I want to figure out what to do if the standard coding doesn't work for running the pump properly.
Hope a well pump installer is on the forum or a motor/pump expert.
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