Rural bi-phase power, rotary phase converter

[StobbHouseMachining]

Hi there, I would be really grateful if someone could offer some advice about breakers and what I am wanting to check a few things about the supply on my farm. I am using an ABB 15Kw motor to make 3 phase from my single phase supply. I am currently running the motor off one 240v phase using a transformer to step up to 415v and starting the motor with a cordless drill for the time being. I am aiming to get the idle motor to start itself with capacitors but i am starting to believe this wont be possible as i am already having to use a D50 breaker to get the motor to idle even after I have span it with the drill. I have built a star delta start circuit and attempted to start the motor with the capacitors but the breaker flips, i believe my only next move up is a D63? But shortly I will be moving to another building that has both phases in. At this point i intend to do away with the transformer and connect the two legs of the motor to each phase to get the voltage i require, is this possible? and also now that i an using two phases I will be using two breakers yes? Meaning that between them I will be able to draw the amount of momentary current to star the motor?

I have looked to for relevant information but haven't found anything that pertains to my particular supply type when reading about and planning to build this thing, I will attach some photos of my bad handiwork.

any help would be great, thanks.

 

[ruggedscot]

This is quite something.... I have to admit that I am concerned about the layouts and the amount of live wiring that is exposed. 15kw from 220v 1ph... thats like 45 amps not taking into consideration losses and the like. Also frequency of your three phase would be all over the shop with that set up as the motor speed would vary with load.

What sort of load are you needing to supply ? what duration ? you could always get this...

https://www.machinemart.co.uk/p/pc-60-5-5hp-phase-converter/
But if you are determined to work on what you have you need to provide a clearer description of what you have and what you are trying to do. How are you getting three phase from the system ? One motor to run up and then take three phases off of the windings ? doesnt really work well that set up, you would be better looking at a dedicated motor generator set.

https://singlephasepowersolutions.com/2019/03/18/1to3-power-source/
https://www.simplypowersupply.com/Single-to-3-Phase-Converter/Rotary/default.aspx

 

[Geoff1946]

Crikey! Don't let an H&S inspector see that! Seriously though that test lash up is potentially lethal.

One moment of distraction or inattention and your family will be arranging a funeral.

 

[ProDave]

But shortly I will be moving to another building that has both phases in. At this point i intend to do away with the transformer and connect the two legs of the motor to each phase to get the voltage i require, is this possible?

No, bi phase will give you 480V not 415.

Bi Phase usually means two tappings from a single phase transformer, so the 2 phases are 180 degrees apart, not 120.

If you can't get a proper 3 phase supply, it is probably better looking at buying a new single phase motor for whatever machinery you have that needs 3 phase, or a proper single phase in, 3 phase out variable speed drive.

 

[ruggedscot]

now this is a whole new level... he can provide a diagram aswell... and give details on starting it etc.

 

[apprentice87]

I built a rotary pahse converter once, and it worked very very well to be honest. I would be here all night writing out the details, BUT you need to know two things.. 1, you have capacitors "in circuit" as it were all the time, this is what generates the "third phase" if you like, and 2, you have additional capacitors that you switch in for starting the motor.. Star/delta starters will achieve nothing as you do not have three phase power to operate one, so forget all about that idea..

Here is mine i made..

john..