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Swimming pool 3 phase motor trips occasionally on earth leakage RCD

CliveS
We have a new 4 kW 3 phase pump motor at the local pool which has a new variable speed drive unit attached and occasionally it trips out on the RCD which I assume is 30mAmp .  The connections are star inside the motor but not earthed which should have stopped it tripping.

We are not sure what to do, we could run the motor flat out and delta connect the windings possibly or some suggest disconnecting the RCD as the circuit is completely separate from normal wiring.  Would this option contravene any of our regs?
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    mapj1:

    However there is an additional complication that motor frames are only made in a limited number of sizes so the chances are that your motor has to be  oversized for the pump, perhaps only by 10% or so, but still oversized. in such a case it can safely be run a little lighter than flat out and still pump the same.


    My understanding is that the intention is that with a VSD, you don't run flat out all of the time. This may well be possible with ventilation systems, for example, less so with a table saw. Whatever the law-makers may think, one size does not fit all!


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    mapj1:

    However there is an additional complication that motor frames are only made in a limited number of sizes so the chances are that your motor has to be  oversized for the pump, perhaps only by 10% or so, but still oversized. in such a case it can safely be run a little lighter than flat out and still pump the same.


    My understanding is that the intention is that with a VSD, you don't run flat out all of the time. This may well be possible with ventilation systems, for example, less so with a table saw. Whatever the law-makers may think, one size does not fit all!


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