2 phase 240 volts?

[Com_VC]

I've got a welder here that requires 2 phase 240 volts, would it be possible to get this to work from a single phase 240V outlet?

Any info would be great.

Thanks

[juan]

I've got a welder here that requires 2 phase 240 volts, would it be possible to get this to work from a single phase 240V outlet?I suspect if it genuinely is a 240v 2 phase welder then it will work on single phase 240v. Are u sure it is not 415v? Personally I have never seen 2 phase 240v anything in Australia and suspect it is from the states or somewhere that has 110v single phase.
With a transformer welder generally the voltage is the issue not the requirement for 2 phases. Higher voltage(2 phase) is used to reduce the amperage on the primary winding and hence reduces the size of the copper windings on the primary side of the transformer and the supply cable.

cheers

[echnidna]

2 phase is 415 volts between the 2 phases.

[Ivan in Oz]

2 phase is 415 volts between the 2 phases.

Must Disagree,
There are a multitude of Phase to Phase Voltages.
415V is the one which comes to mind for Australian Domestic Electricians.

For me Phase to Phase is 11KiloVolts:oo:
But that doesn't power Welders,
Just Stepdown Transformers.

[Cliff Rogers]

You need to know exactly what sort of 2 phase it is.
In the bush we are on a SWER line that has a centre tapped 480V secondary.
This gives out 2 phases of 240v each that are exactly 180° out of phase.
You get 480V if you get between the 2 actives.

In a normal city supply, the poly phase supply is 3 phase with each phase 120° out of phase with each other phase.
This will give you 415V between 2 of the actives.

DO YOUR HOMEWORK CAREFULLY.

[Ashore]

Power supplied on ships is 240v 2 phase with no earth as are some building sites using transformers to supply power ( for safety reasons ) rather than mains power. I think ( and am reasonably sure that ) you would be fine using normal domestic power of 240v otherwise check the welders manufacturers web page if possable or if they have a contact try that :2tsup:

[Cliff Rogers]

Power supplied on ships is 240v 2 phase with no earth .....
:?.... a lot of the Navy boat computer gear that came in for repair was set for 120V including the UPSs.
Maybe it was just the stuff out of the Comm Centre... :think:

[Ashore]

Not realy up on what the navy use cliff mabye they have their own dedicated power supply for the important stuff, but us poor travelers in steel the standard Australian power supply is 240v 50 hz , which was a pain if you got anything with a 60 hz clock in it :doh:

[Brickie]

2 phase was/is 480v, at least in the welding trade.

[juan]

I am surprised to hear about 480v 2 phase being the standard for welders? Have not worked with them for years but they were all 415v in my day.

[Ashore]

Weather single phase , 2 phase or 3 phase the voltage depends on the generator/ alternator producing the power . but 2 phase being 480 volts , not when I was welding , :doh:

[Com_VC]

Ok, this is what it says in the documents.

Can be run on 240, 415, 480 or 380 input voltages.

Then there is a table with Phase: 2
Cycles (Hz): 50

The input voltage is configured by bridging some terminals.

Will this run on single phase?

[Ivan in Oz]

Photo Please:D:2tsup:

To your question.....YES!

Just get the Wiring/connections correct.

[Cliff Rogers]

Ok, this is what it says in the documents.

Can be run on 240, 415, 480 or 380 input voltages.

Then there is a table with Phase: 2
Cycles (Hz): 50

The input voltage is configured by bridging some terminals.

Will this run on single phase?

I guess so.

[Ashore]

2 phase was/is 480v, at least in the welding trade.
was this the standard al , cause I thought the standard for 2 phase domestic in Australia was /is 415v
Guess there is a double standard in the welding trade too :D .

[Ivan in Oz]

3 Phases, 120* between all 3 phases.....This is Normal Domestic in Oz
415V Ph to Ph,
240V Phase to Neutral


2 Phases, 180* between both 2 phases ................Specialised
480V Ph to Ph,
240V Phase to Neutral

When I grew up......Here we go:doh:
We had 24V DC......Truck Voltage

and ALSO
32 Volt single phase,
this was a single Phase Lister Getset, DUG, DUG, DUG, DUG all day long [NO] Not the Old VW Beetle type DUG, DUG, DUG, DUG sound
Phase to Phase was also 32V
One phase was tied to Earth most likely, can't remember if there was an Earth.........This was in the last Mellenium:B

[Cliff Rogers]

2 Phases, 180* between both 2 phases ................Specialised
480V Ph to Ph,
240V Phase to Neutral

Rural power, a lot of the dairies up here use it.


....When I grew up......Here we go:doh:
....32 Volt single phase,
this was a single Phase Lister Getset, ....

We had 32VDC til the late '60s, single cylinder Lister diesel aircooled, more of a Knack, Knack, Knack, sound than the Dug, Dug, Dug that the watercooled ones made. (My grandfather had one of the watercooled ones)
We had a bank of 16 2V lead acid batteries that were bigger than a modern car battery.

[Stringy]

Please refer to my explaination in this thread!

http://www.woodworkforums.ubeaut.com.au/showthread.php?t=39834&highlight=480v

The 2phase bit has me worried though, as these welders when run on 415v still only access a single phase!

[Brickie]

was this the standard al , cause I thought the standard for 2 phase domestic in Australia was /is 415v
Guess there is a double standard in the welding trade too :D .

Pity you didnt do the research.

http://en.wikipedia.org/wiki/Two_phase

[seriph1]

Somewhat off topic (OK totally) but I will be needing a 380 volt 50Hz power supply for an oven I am bringing in to the country from Germany .... anyone got a step-up trannie laying around that will do that for me? Seriously, I think I will need a trannie that can output 10 amps at 380, so any help would be appreciated.

Thanks

[Ashore]

Pity you didnt do the research.

http://en.wikipedia.org/wiki/Two_phase
I don't understand your reference to my not doing my research and then giving a link to an intresting site on 19th century power supply, what has 1895 DC generators fitted at Niagara Falls have to do with welding , they did supply 2 phase power as did a lot of generation systems of the era in fact DC generators were built by edison to power whole cities but were quickly superceeded by 3 phase AC and 2 phase power is not to my knowledge produced comercially anywear :?

[chrisp]

Somewhat off topic (OK totally) but I will be needing a 380 volt 50Hz power supply for an oven I am bringing in to the country from Germany .... anyone got a step-up trannie laying around that will do that for me? Seriously, I think I will need a trannie that can output 10 amps at 380, so any help would be appreciated.

If you think you can get away with 350V (or 360V), it would be easiest to use an off-the-shelf 240V to 110V (or 120V) transformer with the 110V winding wired in series (and correctly phased) with the 240V. This will give 240V + 110V = 350V. (incorrectly phased you will get 240V - 110V = 130V).

It would be easier enough to get another transformer and also wire it in series to make up the extra 30V if required.

The only issue is to watch is the primary to secondary insulation rating of the transformer(s).

[seriph1]

Very interesting thanks ..... can't wait to get this oven and see what happens! :D

[petersemple]

Somewhat off topic (OK totally) but I will be needing a 380 volt 50Hz power supply for an oven I am bringing in to the country from Germany .... anyone got a step-up trannie laying around that will do that for me? Seriously, I think I will need a trannie that can output 10 amps at 380, so any help would be appreciated.

Thanks

I would look at the Tranny's used in Valve power amps. I'm betting you'd find a 380V one - not sure about current rating though

peter

[Uncle Bob]

I would look at the Tranny's used in Valve power amps. I'm betting you'd find a 380V one - not sure about current rating though

peter

Yep, somehow I think a valve radio tranny won't power an oven. I'm guessing it will have to be a kick ass size to power an oven.

Possibly the OP will be able to power this on two or three phase depending on a lot of factors, including if it has electronics. Might need to get a sparky to eye ball the installation manual.

[GraemeCook]

When I lived in the States (Boston) we had a four-wired electrical system, rather than the Australian three wire system. The wires were active, counterphase, return and earth. By connecting between either the active or counterphase and the return wire one got 110 volts AC single-phase. By connecting to between the active and counterphase you got 220 volts two-phase.

It seeems like you may have an American-standard welder. This may or may not comply with Australian standards. This raises all sorts of legal liability and insurance issues.

It may be prudent to check with your state electrical regulator before trying to use it.

Cheers

[petersemple]

Yep, somehow I think a valve radio tranny won't power an oven. I'm guessing it will have to be a kick ass size to power an oven.



Re the oven thing - I have in my online travels recently seen a few australian people selling 415v - 380v 3 phase step down transformersfor operating 380v equipment on Aussie 3 phase. Are you sure the oven is supposed to be single phase?

peter

[Brickie]

When I lived in the States (Boston) we had a four-wired electrical system, rather than the Australian three wire system. The wires were active, counterphase, return and earth. By connecting between either the active or counterphase and the return wire one got 110 volts AC single-phase. By connecting to between the active and counterphase you got 220 volts two-phase.

It seeems like you may have an American-standard welder. This may or may not comply with Australian standards. This raises all sorts of legal liability and insurance issues.

It may be prudent to check with your state electrical regulator before trying to use it.

Cheers

I have worked in plenty of welding shops that have 480V 2 Faced welders, they may be the older type, but they still worked ok.

[seriph1]

The oven has nothing in it that I can imagine would use 3 phase, so I can't see why it would need it.... I can't find the bloody pics the seller took for me, but I am sure it has the single phase symbol after the 380.... that being a 1, then a circle with a line through it........ but hey I have been magnificently wrong before!
:D:D:D

[Gravy258]

http://users.pandora.be/worldstandards/electricity.htm.
Check out this site. The nerds guide to worldwide power.
It says that the yanks use 240v 2 phase.
The question that needs to be asked is where did you get this welder?

[seriph1]

GRAVY

Now that's a brilliant resource - Folks, click on the HOME link and have a read ......excellent information for trivial buggers like me

thanks!

[elkangorito]

2 Phases, 180* between both 2 phases ................Specialised
480V Ph to Ph,
240V Phase to Neutral




This is not correct.

What you are talking about here is what is commonly used in the USA, which is called "split phase". It is not 2 phases. The word "phase" can only be used when electrical phase displacement is exactly 120 degrees.

[juan]

The word "phase" can only be used when electrical phase displacement is exactly 120 degrees.Not true. You can from a technical point of view have any number of phases and hence the displacement could be any number of degrees resulting from the number of phases divided into 360. In most practical applications however the number of phases in power generation is limited to 3 and hence 120 is the most common number of degrees.

Cheers

[chrisp]

Not true. You can from a technical point of view have any number of phases and hence the displacement could be any number of degrees resulting from the number of phases divided into 360.

Jaun is quite correct.


In most practical applications however the number of phases in power generation is limited to 3 and hence 120 is the most common number of degrees.

I think the reason that three-phase is so prevalent is that three-phase is probably the effectivenesses of transmission. The use of three-phase and hence three active conductors (no neutral required) allows three times the power that can be transmitted over single-phase (one active and one neutral conductor). i.e a three-phase transmission line using 50% more copper allows 300% more power than single-phase.

[elkangorito]

Juan is quite correct.


I think the reason that three-phase is so prevalent is that three-phase is probably the effectivenesses of transmission. The use of three-phase and hence three active conductors (no neutral required) allows three times the power that can be transmitted over single-phase (one active and one neutral conductor). i.e a three-phase transmission line using 50% more copper allows 300% more power than single-phase.


My original statement
The word "phase" can only be used when electrical phase displacement is exactly 120 degrees. was meant to be referred to the statement that Juan made,
In most practical applications however the number of phases in power generation is limited to 3 and hence 120 is the most common number of degrees.Advantages of a 3 phase system.
1. For any one machine frame, the output is;

1 phase - about 65%.
2 phases - about 90%.
3 phases - about 96%.

2. The power delivered to or taken from a 3 phase system is more constant. In a single phase system, the power curve pulses at twice the line frequency. With 3 phases, the pulses are 6 times the line frequency & do not cross the zero axis like the single phase system (there is no "zero power" point). Since the power is more constant, the torque of a rotating machine is more constant, which results in less vibration.

3. With one type of 3 phase connection, there are 2 voltages available (Star).

4. A 3 phase machine can be smaller than a single phase machine for the same power output.

5. In a distribution system, the total quantity of material needed for 3 conductors is less than that required for the equivalent single phase system.