3 phase motor on single phase, using only Capacitors

Just spotted this...

How to do it: run a 3 phase motor on single phase supply. part 1

Star to Delta

https://www.youtube.com/watch?v=6UcDM3hm0XM

How to do it: run a 3 phase motor on single phase supply. part 2

Using only Capacitors from florecent lights!

https://www.youtube.com/watch?v=43eAEeyTbs8

Edited By ash roberts on 06/05/2015 05:34:43

Edited By ash roberts on 06/05/2015 05:35:45

Edited By ash roberts on 06/05/2015 05:56:37

I use this method to test three phase motors because plugging a faulty motor into an inverter will blow it up.

the problem with this is getting the motor started. if the motor is vertical with no load it will start, if the motor horizontal with no load some may start but most unlikely without giving it a spin. if the motor is under load you will have to get it up to speed to get it to run. this is not something new this has been known for years, if it worked properly I for one would not have wasted money buying inverters.

I ran my 3 phase milling machine like this for several years and did some good work on it. It also made it easy to move on when we moved house.

I read an article some time ago that said its not uncommon for manufacturers to fit 3 phase motors into appliances intended for use on domestic supply. The reason is one of simple economics apparently, If they can buy suitable motors at a low price and just fit a capacitor then everyone's happy.

A 3 phase motor running on single phase with the help of a capacitor has a poor starting torque and may need a little nudge to show it what is required of it but if the driven machine has a clutch this is not a such a problem as it doesn't have to be started so often although it may still need that slight nudge . A clutch could be something as simple as a slackening drive belt .Interestingly, a friend of mine used a small single phase motor in the manner of a car starter as the 3phase motor doesn't have to reach anything like full speed to develop enough torque. He also used a small motor to start a large single phase motor that would otherwise draw too much starting current! Colin