Converting 3ph generator to 1ph

Bruthal · 16-05-2020 3:50pm

funkey_monkey wrote: »

Owner now wants to know what would happen if he put a 3 plug on the end of the 3 phase outlet?
Would that be any different to his single phase outlets?
My understanding is that 3 phase has 3 hot wires - one for each phase and a neutral. There is also an earth. So he can't get anything better than what the single phase outlets provide him.
Correct?

Yes the 3 phase outlet is just 3 phases and N.

What is the precise use he wants to use the generator for?

Edit: O yes shed, and house backup.

funkey_monkey · 16-05-2020 4:53pm

Bruthal wrote: »

Yes the 3 phase outlet is just 3 phases and N.

What is the precise use he wants to use the generator for?

Edit: O yes shed, and house backup.

I don't think he believes me - either that or he is trying to get out of a hole. Two of them bought.

Bruthal · 16-05-2020 5:47pm

Well the 3 phases are not simply 3 phase wires of course. But in terms of running things like a kettle, it doesnt change anything from before.

It would be interesting to see will it boil the kettle if you added heaters to the other 2 single phase sockets

funkey_monkey · 16-05-2020 8:06pm

Bruthal wrote: »

It would be interesting to see will it boil the kettle if you added heaters to the other 2 single phase sockets

Why would that make a difference. - something to do with load balancing?

autumnalcore · 16-05-2020 8:22pm

Thread has gone from 'what's the best way of doing this properly' to if I throw away 4kw of power (probably 10kw of petrol) can I boil a kettle.

The fella bought the wrong thing for the job, no good will come of your trying to fit a square peg in around hole.

Even if you break your back cutting the proverbial corners off the peg and beating it into the hole with a sledgehammer you'll still have no thanks from fella that 'doesnt believe you' and when the Chinese ****e blows up down the line which I can 100% guarantee it will you'll have a big target painted on your ass.

Bruthal · 16-05-2020 8:41pm

Feck it in anyway, no boiling the kettle so.

16-05-2020 9:28pm

I'm sure there were kettles before electricity.

foxy farmer · 16-05-2020 10:09pm

What size engine is driving the alternator?

funkey_monkey · 16-05-2020 11:34pm

6.5hp.

I've suggested his shed is changed over to led lights which will get rid of halogen floodlights that are currently in place and also swap old the old bulbs too. That should reduce the burden on the generator.

If he desperately needs a kettle I've told him to put in a gas hob or get a caravaners kettle which is only 1kW.

17-05-2020 1:02am

funkey_monkey · 17-05-2020 4:32pm

Any details on that setup and costings?

17-05-2020 6:58pm

DIY from job leftovers, orphan batteries no good for starting engines, upspec rejects and a few eBay bargains.

17-05-2020 7:24pm

600VA Modified square wave inverter, 150W solar

Runs the LED lights and an occasional brushed motor April to November. The battery is removed and charged off-site in the Winter. The system has two batteries. Parallel in sunny weather. Hot-swapped in Winter.

User has only reversed polarity and blown all the fuses once, lucky no further damage. I advised against building a liability into the device and advise was declined.

Not my barn by the way. I don't generally fit square waivers or high frequency inverters.

air · 17-05-2020 11:43pm

funkey_monkey wrote: »

6.5hp.

I've suggested his shed is changed over to led lights which will get rid of halogen floodlights that are currently in place and also swap old the old bulbs too. That should reduce the burden on the generator.

If he desperately needs a kettle I've told him to put in a gas hob or get a caravaners kettle which is only 1kW.

It's a joke of a machine so, a 13hp engine is normally used to drive a generator of that kind of size.

6.5hp is only 4.84kW, it hasn't a hope in hell of outputting 6kW of electrical power.
If it was coupled to a single phase head it would be good for about 3kW continuous at best.

17-05-2020 11:51pm

Seeing as the truth is coming out that's probably a 800VA > 1200VA^
The ouput will look the same as the scope photo above..

foxy farmer · 18-05-2020 12:41am

air wrote: »

It's a joke of a machine so, a 13hp engine is normally used to drive a generator of that kind of size.

6.5hp is only 4.84kW, it hasn't a hope in hell of outputting 6kW of electrical power.
If it was coupled to a single phase head it would be good for about 3kW continuous at best.

Not when it's protected by a 3A C rated MCB. :rolleyes:

funkey_monkey · 18-05-2020 11:26pm

Okay - I can get the kettle to boil (after 10:34min

) but only on the 3rd single phase outlet.

Output 1 - which I was originally using has an undervoltage (380V down to 300V) when the load is applied (see photo)
Output 2 - has an overvoltage (off scale) when load applied and hard labouring noise so was turned off before something failed
Output 3 - slight dip in voltage but boils kettle in just over 10min

Question is - what is going on here with the different behaviour for each output?

Kettle itself is irrelevant now - it was just a load here.

air · 19-05-2020 8:31am

Like I suggested earlier it sounds like the AVR is only monitoring one phase - possibly the one connected to output 2 since it's the only one that the generator reacted to.
The kettle is overloading that phase and it's an unbalanced shock load hence the labouring.

funkey_monkey · 23-05-2020 1:56pm

Got asked to take a look at it this morning.
Looks like the stator for burnt out, no voltage!

funkey_monkey · 23-05-2020 2:21pm

Tried to get a voltage across the brushes, it should be 5v, but the reading was reading over the place.
Same with both sets of windings.

air · 23-05-2020 3:21pm

Time to move on & pick up something more suited to the task at hand.

funkey_monkey · 23-05-2020 4:23pm

That is what he was told, but its a new generator/engine so he is looking to get a new set of windings installed by a nearby repair shop.
Maybe even change over to a single phase unit.

air · 23-05-2020 5:02pm

If he can get it rewound single phase or put a new head on it that would be a good option. Hard to imagine it would make economic sense though.
Presumably it was the 2kW kettle that did the damage?

funkey_monkey · 23-05-2020 5:18pm

air wrote: »

If he can get it rewound single phase or put a new head on it that would be a good option. Hard to imagine it would make economic sense though.
Presumably it was the 2kW kettle that did the damage?

2kW kettle plus approx 1.5kW of lights - didn't realise kettle was still switched on until damage done.
Voltage dropped to zero which I thought meant it needed reflashing but was able to make drill rotate, a pile of smoke and that was that.

Bust a drill previously with him too.

funkey_monkey · 04-06-2020 11:16pm

https://m.uk.dhgate.com/product/diesel-engine-generator-for-industrial/475630564.html?f=bm%7cGMC%7cpla%7c1670763299%7c61518981061%7c475630564%7cpla-301146456863%7c011014001003%7cGB%7cdetmotor%7cm%7c2%7c&utm_source=pla&utm_medium=GMC&utm_campaign=detmotor&utm_term=475630564&gclid=EAIaIQobChMIgbOCppbp6QIVZIBQBh2JtgJnEAQYASABEgJpWfD_BwE#redirect_detail=PC2WAP

Been asked about this one...

It looks 3 phase to me. Chinese too. Told him he needs a single phase unit. He seems to think that the single posse of it will be enough for his needs.
Can anyone recommend a 'cheaper' brand of single phase generator?

autumnalcore · 05-06-2020 2:05pm

funkey_monkey wrote: »

He seems to think that the single posse of it will be enough for his needs.

As I said previously a person like this will give you no thanks and you will end up getting the blame when it blows up down the line.

I can only assume this 'fella' is relative and not a client client otherwise you would have washed your hands of it weeks ago?

If you want to give them advice they would be far better off getting a used generator with a honda, kubota, briggs etc branded engine that you will be able to get parts for 2, 10, 20 years down the line than some chinese ****e that blows up after 6 months. I'd take a 40 year old lister over that thing.

funkey_monkey · 06-06-2020 1:39pm

Yes, relative. Won't listen.
Talking to a wall.

Won't listen when I tell him to get a single phase generator as he sees these bargains on these websites.

autumnalcore · 08-06-2020 11:49am

Does he realise that generator is at least €665 after shipping, vat, duty and administration fees?

If theres a problem the seller will probably say no problem just return it and we'll send you another one :rolleyes:

08-06-2020 12:09pm

autumnalcore wrote: »

As I said previously a person like this will give you no thanks and you will end up getting the blame when it blows up down the line.

This.

Avoid, avoid, avoid.

If a single phase supply is required buy a single phase generator, anything else is just messing and will result in a highly pi55ed off end user.

funkey_monkey · 08-06-2020 12:46pm

autumnalcore wrote: »

Does he realise that generator is at least €665 after shipping, vat, duty and administration fees?

If theres a problem the seller will probably say no problem just return it and we'll send you another one :rolleyes:

Refer to:

funkey_monkey wrote: »

Yes, relative. Won't listen.
Talking to a wall.

08-06-2020 1:35pm

funkey_monkey wrote: »

Yes, relative. Won't listen.
Talking to a wall.

Won't listen when I tell him to get a single phase generator as he sees these bargains on these websites.

Just walk away.

This will cause far less friction than will be caused by him wasting money on a “solution” that is not fit for purpose. I have been don this road before.

funkey_monkey · 13-01-2021 4:30pm

Latest question is will the following fit in to replace the generator in his current broken one?

I'm aware his current generator is 3-phase and below is a 1-phase winding, but there is a 3-phase setup for €210 if the wiring will not suit.
I think it would need an AVR etc.
I need to check the dimensions, but what else are the potential issues so I can give him an answer.

https://www.ebay.co.uk/itm/Stator-Rotor-Coil-Power-Generator-For-6-5-7-Ps-1-Phase-From-Detec/174310213828?_trkparms=aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20201210111314%26meid%3Da04dd3200e4045488633176abeb803f4%26pid%3D101195%26rk%3D2%26rkt%3D12%26mehot%3Dpf%26sd%3D254795564849%26itm%3D174310213828%26pmt%3D1%26noa%3D0%26pg%3D2047675%26algv%3DSimplAMLv5PairwiseWebWithDarwoV3BBEV2b&_trksid=p2047675.c101195.m1851

Converting 3ph generator to 1ph

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