What happens if...

[Maker]

I've got some pictures on here of where I did it, I'm pretty sure I put heatshrink over all the connections and tie wrapped them back down. I'll have a look inside it at Easter and see what kind of state they're in.

Seadog just reminded me, I actually got the polarity mixed up and basically just guessed, it works so I guess I got it right, no idea what would happen if I got it wrong, probably half a turn, fart and let the smoke out but hopefully you won't find out.

 

[Seadog]

I've never tried it, but I think the motor would not run but sit and buzz before overheating. The polarity is important so as to maintain a rotating magnetic field. If one coils is wired backwards it will oppose the rotation driven by the other two coils.

 

[Dieselman 63]

I've never tried it, but I think the motor would not run but sit and buzz before overheating. The polarity is important so as to maintain a rotating magnetic field. If one coils is wired backwards it will oppose the rotation driven by the other two coils.

So I need to disconnect the star, then once the wires are extended link the ones that are opposite each other in the stator windings?

I've got some pictures on here of where I did it, I'm pretty sure I put heatshrink over all the connections and tie wrapped them back down. I'll have a look inside it at Easter and see what kind of state they're in

Got a link for that?

 

[Dieselman 63]

New lines soldered and heatshrinked on, first bit of string re-done. I did the opposite wires different colours so there are two red, two blue and two yellow so as to make it easier to see what's what. There's a first time for everything...

 

[Dieselman 63]

And it continues... Almost ready to refit the rotor

 

[Dieselman 63]

You do know which ones were the original ends still, yes?

No I mixed them all up and assigned the colours randomly

Joking. I added flags to the end of the ones which came off the star point and the opposite wires have the same colours

 

[Maker]

Got a link for that?

Yep, here.

 

[Dieselman 63]

Yep, here.

Look at you using cable ties, over here I'm using string and varnish, gotta keep the restoration authentic!!

 

[Maker]

I didn't consider it a restoration, more a modification.

 

[Dieselman 63]

As @pdg rightly says I should test the circuits using a multimeter. I am going to town tomorrow, so I will buy a multimeter

 

[piman]

Hello Diesel

http://www.motors-direct.co.uk/index.php?_a=product&product_id=219

.55Kw 2 pole, near enough to 3/4 H.P. by my reconing?

Alec

 

[Dieselman 63]

Hello Diesel

http://www.motors-direct.co.uk/index.php?_a=product&product_id=219

.55Kw 2 pole, near enough to 3/4 H.P. by my reconing?

Alec

Yup .55kw is 3/4hp. I'm not sure why you've linked me though...

 

[Dieselman 63]

You happy with how to wire it?

Me or Piman? I already have a motor for my machine, this whole exercise is so I don't have to buy a 1ph replacement...

And not really, help will be required at every stage of the way! Multimeter will be bought for testing tomorrow, vfd will be bought next week (and arrive in three weeks - groan).

 

[Seadog]

See post No. 25

 

[Dieselman 63]

See post No. 25

I've got what I think are the pairs - if they're opposite on the stator?

 

[Dieselman 63]

You need to identify the windings, they're not necessarily going to be opposite...

So, you've got your original wires that came out - use your new multimeter to find which of the star point wires is related to which of the originals.

Then, you have pairs, call them 1, 2 and 3. The colours may or may not match...

Then

View attachment 129987

If the rotation isn't what you expect, swap any two of the input wires.

Legend. Thank you ^.^

 

[zx9]

Yup .55kw is 3/4hp. I'm not sure why you've linked me though...

Exactly, I would have offered you the one that came off my Drummond but I did not think you would want to ship it half way round the world.

 

[Seadog]

I've got what I think are the pairs - if they're opposite on the stator?

In its simplest form there are 3 coils, spaced at 120°. However, in practice, the coils are spread around the periphery of the stator in groups of three. This gives a more uniform and smooth rotation.

https://commons.wikimedia.org/wiki/File:Asynchronmotor_animation.gif

 

[piman]

Hello Diesel.

the reason I linked it is that it is a 3/4 H.P. 2840 rpm motor which you said you could not find. And a good price also.

Alec

 

[Seadog]

But do they ship to NZ for nothing?