I need some help undersatanding 3 phase motors

If your supply voltage was 236 volts and each phase of the motor balanced out at 235 you couldn't get any better!

That said you may need to adjust capacitor values just a bit once it running under a load however if the running volts at load are within +- 20 volts its still an optional adjustment.

tcmtech said:

As a last resort you can also use a pair of DC electrolytic capacitors in reverse series connection to make a big motor start capacitor. I have been using a pair of 450 VDC 2700 uf electrolytics as the motor start capacitors for my 15 HP industrial air compressor for at least three years now without problems. I have them configured in reverse series + to + with the -'s as the input and output. The work out to the equivalent of being a single 450 VAC 1350 uf motor start capacitor. BTW at startup in the winter they can see as much as 130 amps going through them for up to around 10 seconds while the compressor gets up to speed.

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I have been experimenting with the back to back electrolytic capacitors and that works very well. Those caps were free, salvaged from old CRT TV sets, dumped at the side of the road.
Just build a 3 Phase rotary converter with a 470uF and 330uF Cap back to back rated at 400 Volts which gives me 200 uF for starting with a 5 HP motor from a single phase supply.
Then to get the higher voltage I switch from delta to star by means of contactors to get 400 Volts out of a 240 volts supply.
By experimenting with the run capacitors voltages up to 500 Volts 3 phase are obtained.

Thats a pretty cluttered living space RODALCO I would fit a Total Power Kill Button next to my bed at night , I would not sleep thinking I had left a light on !
I was entertained by your testing and that explained the back to back TV Electrolytics . I did not understand that before. I noticed a resistor soldered across my start capacitor and guessed that must be the reason but you have confirmed it with explanations also on your UTube video. Thanks I was not able to log in to UTube . Don't know what the problem was so I post it here

I can also recommend Surplus Equipment store in the States as an excellent cheap supply store for capacitors
https://www.surpluscenter.com/
see post 36 for some price examples of stuff I bought and only about a week from order to delivery in Aus
Postage of $75 is the killer but whichever option you choose is the same price so I went with the fastest and best.