Quote Originally Posted by 2e0poz View Post
A servo to replace a 3hp equivalent motor would cost a lot of wonga?
Either 350+vat or 434+vat from zapp depending on if you want speed or torque in the 2.3-2.4kw range.
Plus another 304+vat for a suitable drive...


Getting back to the original post, I got a custom step-up transformer made to build a RPC, but I can't for the life of me remember the name of the company.
Regarding getting a neutral, if the idler motor is a 240/415V motor, then when wired in star config for 415V operation, the star point will provide a neutral for the three phase. That's how I use a 240v contactor to drop out the start capacitors once my RPC idler is upto speed. However, the neutral will be at 240v in relation to earth, instead of the usual 0v, and with the transformer acting as an isolator, you've got to be careful of electric shocks. I installed a three phase RCD as part of my RPC to minimise the risk.