Run 400v compressor of 230v

[UV]

the picture wasn't clear enough to zoom in. You may need to put a new contactor in as the amp draw will be almost double what it was on 400v. If the contactor is rated for the amp draw at 230v then you won't have to swap it. It may well be. Should pull somewhere around 8a at 230v vs. 5a at 400v. Contactor is likely big enough

I added higher resolution picture now. Yes, the amp draw is 7a when run off 230V. I will check the contactor. Thanks.

 

[Wookie]

You may also need a new transformer for control voltage. I don't know what Bauers run on, but it's usually transformed from one leg of the 3 phase, and if you drop from 400 to 230, you will also need to make sure your control voltage is correct.

 

[lionfish-eater]

Three phase power comes in two different configurations.
Delta or Y.
If you look at the voltage lines on your picture you will notice either a delta or a Y.
You need to know what type of three phase power you have.
You might want to hire a pro if you don't know what I am referring to.

 

[michael-fisch]

I hope that you aren't really having to live with 29Hz AC, not only do the lights visably flicker at that frequency, but more important, the cores of electric motors designed to run at higher frequencies are constantly saturated which does a good job of damaging/destroying them. Motors designed for those frequencies are few and far between and weigh much more (like at least 60% more) than 50 or 60Hr motors do.

Michael

 

[michael-fisch]

Otherwise if you are running 3 phase 230V just wire the motor with 3 phase delta wiring instead of 3 phase Y wiring. If you are running off single phase 230V your electrician can rewire the input by adding 2 large capacitors and therby creating 2 delayed phases, offset by 120 and 240 degrees. Now you have a rough 3 phase current for your motor, coming from your single phase wall outlet. If you really have 29hz power, the needed capacitors are going to have to be a lot bigger than for 50 or 60hz.

Michael

 

[stepfen]

As I understand the inverter drive will maintain the voltage and frequency ratio; so a "400v 50hz" motor will run fine at "230v 29hz", but with somewhat less rpms.

That's simply not true, so please forget the 29Hz and the idea of an inverter in general.
If you have real 3 phase voltage supply then it is just a matter of wiring. If you have a single phase supply, it is still possible with some extra components (capacitors) as said above.
A professional should be able to do all these very easily.

 

[Charles2]

You may also need a new transformer for control voltage. I don't know what Bauers run on, but it's usually transformed from one leg of the 3 phase, and if you drop from 400 to 230, you will also need to make sure your control voltage is correct.

I suspect that is why the connections are labeled as wye for the higher voltage and delta for the lower voltage. The control voltage probably comes from neutral to a leg on high voltage and from leg to leg on the lower voltage.

Just hire a competent electrician to hook this up and I think you will be OK.

I still have questions about the 29Hz. That just doesn't sound right to me.

Also, if your frequency is 60Hz instead of 50Hz, you will need to downsize your drive pulley to approximately 83% of the existing pulley.

 

[Dave1w]

I think the comments on reconnecting it form Star to Delta is the way to go.

Just for info, when i was talking to an inverter company about whether I could use to run a 415V motor through an inverter from 240V single phase they did say it would end up with a 29hz supply. They recommended to first rewire it as a 240V 3 phase if I could (as most are dual voltage).

This would't be an issue if the original motor could be rewired to 240V 3 phase, but as mine is 4kW it was a 415/680(?) motor, I couldn't.