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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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    well this is a 4000w unit. Let us assume that the vsd saves us 5%, or 200 watts, could be more, or less, but a nice easy number to assume pump works just fine at 95% of full power.

    . Now I do not know the OP's electricty supplier, but pretend that it is 10p per kw hr. Could be twice that, unlikely to be half.so, saving 48p a day assuming 24 hour running.

    We get the hundred quid back in 200 days of operation, anything longer before it needs replacement is clear profit - That would be a disappointingly short working life, ten years might be more sensible, so it really should pay for itself.


    I fully agree it is not worth bothering with kit that only runs very  intermittently, but fans and pumps often really are 24/7 and can often be left running but backed off at night, and again the VSD helps that


    The kettle thing really is cobblers though - it is better to go the other way and flash boil water as required with lots of power, as there is then no time for loss of energy to the environment.

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    well this is a 4000w unit. Let us assume that the vsd saves us 5%, or 200 watts, could be more, or less, but a nice easy number to assume pump works just fine at 95% of full power.

    . Now I do not know the OP's electricty supplier, but pretend that it is 10p per kw hr. Could be twice that, unlikely to be half.so, saving 48p a day assuming 24 hour running.

    We get the hundred quid back in 200 days of operation, anything longer before it needs replacement is clear profit - That would be a disappointingly short working life, ten years might be more sensible, so it really should pay for itself.


    I fully agree it is not worth bothering with kit that only runs very  intermittently, but fans and pumps often really are 24/7 and can often be left running but backed off at night, and again the VSD helps that


    The kettle thing really is cobblers though - it is better to go the other way and flash boil water as required with lots of power, as there is then no time for loss of energy to the environment.

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