Single to 3 phase transformer on eBay

[Zenith]

Hi All,

 

I'm looking to buy a 3-phase transformer and there's one on eBay but the seller is not making much sense.

 

He has it for sale on a buy it now for £20.00 but the postage is £180.00.

 

https://www.ebay.co.uk/itm/3-phase-transformer/303095123661 (there are two for sale)

 

I've asked him about the postage. The dialog is below:

 

 

Me: Is that postage charge correct?

 

 

Seller: Have much you can give me mate price I sent cheaper

 

Me: I use Interparcel. Try it yourself: https://uk.interparcel.com/. My post code is...

 

 

Seller: If you need have much you pay for this.I'm bay 240 paund and not juset I have in garage 240 watts

 

Me: I'll pay the £20.00 price for the transformer and up to £20.00 for the postage. So a total of £40.00

 

Seller: Not thanks.I'm pay 240 20 paund

 

Me: I don't understand. How much is the transformer & how much is postage?

 

Seller: I'm not sale 20 paund to less.I'm bay 240 and not sale 20 paund.way postage 180 paund

 

I guess I'm being thick.. I read it as he doesn't want to sell at my suggested offer, but why has he listed in this way?

 

Thanks

 

 

[david.elsbury]

Who knows. Maybe he just wants 20£ for it? But it will be very heavy, which means postage will be very expensive.

 

Lots of insane people selling stuff online. Looks like he’s not good with English either. :/

Edited April 21, 2019 by david.elsbury

[James Remo]

It used to be the case that the ebay fees didn't include the postage, so you used to see low price, high postage items a lot on ebay. Since fees started being based on final price including postage this happens a lot less. Offer him the £20 and tell him you'd like to collect, see what he says.

[Jivemaster]

Certainly harks back to the historic practice of low price high postage to evade fees.

 

Are you absolutely certain that it's the transformer that you want??? I think I'm looking at a single to three phase motor converter unit.

 

see www.machinemart.co.uk/p/pc-20-2hp-phase-converter/

Edited April 21, 2019 by Jivemaster

[pscandrett]

Seller: If you need have much you pay for this.I'm bay 240 paund and not juset I have in garage 240 watts

 

Seller: I'm not sale 20 paund to less.I'm bay 240 and not sale 20 paund.way postage 180 paund

 

As an aside, I think they're trying to say that they bought it for £240 and won't sell it for £20.

 

I don't understand why he's biasing it with mega-postage - he's done the same on his other auctions too - unless it's the way he used to do it to evade large ebay fees.

 

(As another aside, a wild stab in the dark is that your seller is Albanian - they seem to call our currency 'paund sterlina'. I'm not enough of a linguist to try to work out the actual semantics and syntax of what is written. Playing with google translate isn't helping any further.)

[Brian]

As Jivemaster says, it's not a transformer but a converter to drive three phase motors on single phase mains. So it's a couple of capacitors and a toggle switch in a box.

[paulears]

I didn’t know Royal Mail parcels took items as heavy as these transformers?

[Zenith]

Many thanks for all your thoughts on this.

 

As many of you suggest, I think the chap is under the delusion that he won't be charged commission on postage.

 

The transformer in question is suspect as to the internal wiring and whether the o/p is delta or Y.

As you say, it's probably a motor converter. The labels on the box point in that direction.

 

As an aside, If anybody knows of a second hand 3Ø transformer please let me know.

 

Thanks again

[Brian]

The transformer in question is suspect as to the internal wiring and whether the o/p is delta or Y. As you say, it's probably a motor converter. The labels on the box point in that direction.

 

If it's a motor converter then there is no transformer involved (well, there is but it ain't three phase). The schematic of the unit Jivemaster linked to above...

 

[Jivemaster]

Once you deal in second user big transformers be sure that you have the means or commercial contacts to assure yourself that they are in good condition. If you have an occasional need then look into specialist hirers, if you have a regular and frequent need look into purchasing one new from a manufacturer (try Brush in Loughborough amongst others )

 

I've seen odd transformers in military surplus places, obviously spec and condition unchecked.

 

There is/was a firm in SW London who hired these out fully tested. Was represented here as "Backroom" IIRC once.

[Zenith]

This looks more like what I'm after:

 

https://www.ebay.co.uk/itm/BIRMINGHAM-TRANSFORMER-LTD-3PHASE-3PH-415V20A-AC-TESTING-TEST-PAD-BENCH-AB6-USM7/132483564090

[Brian]

As long as you want 24V out.

[adam2]

I can not recommend any device of this sort. They all use a tapped transformer and capacitors to produce not very good fake 3 phase in order to drive a three phase motor from a single phase supply. The output is nothing like proper 3 phase and will cause extra losses and heating in the driven motor, unless considerably oversized this motor will likely succumb quickly to overheating.

 

I used to work for a company that manufactured these phase converters, ours were of good quality but still subject to the fundamental limitations of the technology. That was decades ago, and this sort of thing should be regarded as obsolete. To work a three phase motor from a single phase supply, purchase a 3 phase motor drive inverter with single phase input. These are widely available.

 

To operate non-motor 3 phase loads from a single phase supply, the best approach is to accept that it cant easily be done. Obtain a 3 phase supply or a single phase load. It is possible to obtain a 3 phase alternator and to mechanically drive this at the correct speed from a single phase motor. The costs, complications, losses, and starting problems are most unlikely to make it worthwhile.

 

 

 

[Jivemaster]

What do you actually need three phase for? and where do you intend to get it from? Your choice of supplier -ebay worries me as you have no warranty that the seller even knows what they are selling, and you will have no idea what you have 'til it arrives at the end of a heavy (hence expensive) transport journey.

 

If you are stretching your knowledge and competence then spend the money on professional advice. A transformer failure is NOT usually a trivial event with three phase.

 

http://www.backroom.co.uk/

[Zenith]

Thanks all,

 

The reason for this enquiry is that I'm considering upgrading my table saw to a much larger machine.

 

 

This kind of thing: https://www.rjmachin...d/altendorf-f45

or this: https://www.ebay.co.uk/itm/Striebig-Compact-11-Type-4164-Vertical-Wall-saw-Excellent-9950-VAT/332823157913

 

Getting a 3-phase mains supply installed will cost as much as the machine.

 

Logically I need to lower my sights.

Edited April 22, 2019 by Zenith