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oxy moron
03-24-2009, 02:23 AM
I've decided that I want to buy a "220 volt" welder because 110 doesn't have enough top end. It has been suggested to me, that "220's" are more future-proof. So I'm looking at these welders:

Miller Millermatic 180 230volt
Hobart Handler 187 230/240 volt
Lincoln Power Mig 180C and SP-180T 208-230 volt

I'm gonna venture to guess that Lincoln's 208-230 voltage rating means it will run as long as its getting at least 208 volt, and up to 230 volts. Which will work, if i install a 220.

The Miller's 230 volt and Hobart's 230/240 volt?????? i'm confused, Is there a way to wire for 230 volt? whats the difference between the regular 220volt wiring and the 230/240 wiring? yeah, i know the difference is 10/20 volts, but why is it specified that way?

David R
03-24-2009, 07:41 AM
What you need to make sure is its single phase. 208 usually 3 phase. The rest is not important. All the machines you listed should be fine.

David :)

tresi
03-24-2009, 09:11 AM
I have an older Lincoln155 and they indeed are single phase 208 capable. You must move a jumper on the transformer for 208 use. 230 and 240 are nominal figures that can be considered interchangeable as long as you're change single phase to single phase.

duaneb55
03-24-2009, 10:12 AM
oxy moron,

115, 230 and 460 are the actual voltage values with 110/120, 220/240 and 440/480 the typical 'above'/'below' nominal references. 208 can be a single phase voltage too as tresi points out but not a normal 'household' voltage but frequently found in commercial applications such as a 3 phase low leg power.

Ken Dennis
03-24-2009, 10:33 AM
220v is an old adage, from way back when, most 220 hookups these days here in the US will range from around 230v to 240v.
Mine in my shop stays around 238v.
You can run one of the older type welders built back when 208v was a standard and that was designed to run on around 208v single phase on a plug that is producing a higher voltage like 240v, but you would not want to run one that is rated for 230v/240v on a plug that is producing only around 200v like the old 208v average, it would soon burn out the transformer.
I have an older mig that was designed for 208v, and its not changeable to 240v, I run it on my shops 238v, the only thing it does is it causes the DC output from the transformer to be raised a bit, so instead of having a DC output of 17v to 35v, it now puts out 20v to 41v DC.

Before plugging it in for the first time, I ran all this through a couple of techs to find out if I was going to burn it up or not, and all that I said above is what they told me!

MoonRise
03-24-2009, 11:47 AM
For all practical purposes, 220 and 230 and 240 volts all refer to the 'same' voltage and hookup.

And for all practical purposes 110 and 115 and 120 volts all refer to the 'same' voltage and hookup.

Both of those voltages are typical single-phase 'household' voltages in the US. The power coming into the house has two 'hot' wires and a ground wire. Each of the hot wires is 110/115/120V above or below the zero reference level of the ground wire. And because of the sinusoidal wave of the voltage, the two hot legs are out of phase with one another and thus have a voltage difference between them of 220/230/240V.

The different voltages or the different voltage 'names' come about because of old habits and old timers and slight changes in the voltage infrastructure and the normal-and-acceptable 5% general tolerance level on line voltages. In the US, that 5% tolerance means the nominal 120V lines are still considered 'in-spec' from 114V to 126V.

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

What about 208V or 200V, you ask? As mentioned, that comes about from 3-phase power systems (which you typically do NOT have at your house) where a Delta transformer/wiring is used by the power company and the three different wires/legs are such that two legs are 120V with respect to neutral and the third leg is 208V with respect to neutral while all three legs together are 240V 3-phase power.

http://en.wikipedia.org/wiki/Split-phase_electric_power

The 200/208V is similar to the 110/115/120V nomenclature difference, and sort of also occurs because the transformer on the power pole may have 208V on the one leg but by the time the power actually gets to the consumer/user it may have dropped to 200V or so (especially under load).

Some equipment can handle the voltage differences, sometimes with performance changes and sometimes without. And some equipment can not handle those voltage differences and should/must be hooked up to the correct specified voltage and/or some internal wiring jumpers/etc must be connected to match the incoming voltage.

All those 'modern' machine should have no problem when connected to your house's 240V single-phase wiring. Most will also work OK (but with some amount of power loss on the output) if wired to an outlet that has single-phase 208V.

lugweld
03-24-2009, 12:02 PM
The 208 reading is three phase, but Duane, David and others can correct me if I am wrong. However, that is the reading between two legs/phases of the power and not all three legs are used.

MoonRise
03-24-2009, 12:23 PM
lugweld,

208V comes FROM a 240V three-phase system (specifically a Delta sytem), but it is typically just one leg of that system (the "high" or "wild" leg) compared to neutral.

The three 'hot' wires in that system are 240V from leg-to-leg, and two legs are 120V compared to neutral and the third leg is 208V compard to neutral.

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

For a typical house, you don't have to worry about that sort of thing as not many houses have three-phase power!

mark8310
03-24-2009, 12:56 PM
.... can correct me if I am wrong. However, that is the reading between two legs/phases of the power and not all three legs are used.

Happy to correct you, luggy ...... I have delta three-phase here.

Reading from ground to each leg .... 120 120 208

Reading between ANY TWO of these legs (between the two 120's, or between the 208 and either of the 120's) is 240.

Since I have a neutral going back to the transformer on the pole, I can thus use 240 three-phase, 240 single phase, and 120 single phase. Not sure if or how, or even if I would ever want to, use the 208 by itself.

Broccoli1
03-24-2009, 01:13 PM
My 3-phase I get 120v L1,2 or 3 to N

Betwixt legs= 208v

Ok it comes in Delta and then through anutter Transformer to get my Wye:cool2::cool2:

MoonRise
03-24-2009, 02:36 PM
All this 3-phase isn't really applicable to the OP in his house.

But mark, with 3-phase 240V Delta you can't get 240V single-phase. You can get 240 3-phase, and two separate 120V single-phase lines AND a 208V single-phase line (which can sometimes/often be used in place of a 'true' 240V single-phase line). But not 240V single-phase, because the 240V is phase-to-phase between any two phases/legs of the three phases/legs. Those two legs are not 180 degrees out of phase (as 'standard' 240V single-phase power is), but are 120 degrees out of phase (as is appropriate for 3-phase power). Resistive loads won't really care, as they only use volts and amps and pahse or line frequency mostly don't matter to them. Tranformer loads or electric motor loads DO care, as they need the appropriate voltage and amperage and frequency and phasing to work (properly, well, or at all, depending on how 'off-spec' conditions are compared to the 'right' conditions).

Analogy. 240V single phase is like a V-twin or flat twin engine. Using two phases of a 3-phase system is like having only 4 cylinders firing in a 6-cylinder engine. Oops.

And Broccoli is just 'special' :laugh: :drinkup:

denrep
03-24-2009, 03:25 PM
All this 3-phase isn't really applicable to the OP in his house. . . .

Agreed,

So as to the original question:
A transformer type welder is going to be tolerant of some input voltage variation.
I would say that the rating has to do with other internal components, such as motors.

By using 230v versus 240v component ratings, a machine can be connected to a 208v system because the input voltage is within 10% of the data plate rating.
240v - 10% = 216v... 216v is out of range for 208 volt connection. BUZZZZ! Lost welder sales! :mad:
230v - 10% = 207v... 207v is within range for 208 volt connection. DINGGG! More welder sales! :)

As to three phase:
I would have to question some of the posted three phase theory, and would recommend carefully confirming the information before applying it.

Here are the pictures, to illustrate:
30699

30698
:waving:

Turkey
03-24-2009, 04:27 PM
I was recently looking to buy a TIG machine for personal use. I was looking at a Miller and the TigMate. The specifications for both machines were 230 single phase. I have 208 single phase avaialble and knew it fell in to the old +/-10% rule, but wanted to make sure. I talked to the Techie's at both Miller and Hobart and was told by both guys that 208V single phase would do fine. I bought the Diversion and have been using it on 208VAC for two months w/o a problem. Hope this helps.

MoonRise
03-24-2009, 04:40 PM
denrep,

Nice field-expedient compass. :drinkup:

How was the grilled cheese sandwich? :D Was that soup or some stew-substance or some chili in the bowl?

There, have we strayed and highjacked poor Oxy-moron's original question enough? :laugh:

Oxy, any of the machines that you listed should work just fine at your house when fed 208/220/230/240V single-phase power.

oxy moron
03-24-2009, 05:24 PM
cool, thanks all for clearing this up for me.

now lets melt some metal.

denrep
03-24-2009, 05:37 PM
denrep,

Nice field-expedient compass. :drinkup:

How was the grilled cheese sandwich? :D Was that soup or some stew-substance or some chili in the bowl?. . .

Ooops I goofed. :blush:
I posted the three point hitch, (nearly) level lift illustrations, instead of three phase power pictures; oh well.

FWIW - The sugar packet and sandwich were tractor attachments. :laugh:

Good Luck

Broccoli1
03-24-2009, 05:49 PM
I thought it was the Hail Mary play:drinkup:

MoonRise
03-24-2009, 06:01 PM
Ooops I goofed. :blush:
I posted the three point hitch, (nearly) level lift illustrations, instead of three phase power pictures; oh well.

FWIW - The sugar packet and sandwich were tractor attachments. :laugh:

Good Luck

Three-phase versus three-point hitch, eh? :laugh: :p

But, how was the sandwich and what was in the bowl? :drinkup: :waving:

Was there some question about a welder or welding somewhere? :laugh:

Oxy,

The 120V MIG machines have a use and a niche. But the 180-class 240V machines have more oomph for not all that much more money, as long as you have or can get 240V single-phase power.

farmersamm
03-24-2009, 06:19 PM
GROUND IT TO NEUTRAL!!!:laugh::laugh::laugh:


I HATE ELECTRICAL STUFF!!!:realmad::realmad::realmad:

weldbead
03-24-2009, 06:20 PM
maybe for shhtttts and giggles get a electric test meter and stick it in a dryer outlet to see what yer local power company is pushing out...

Tigster200
03-24-2009, 06:26 PM
I live about 1/4 mile from a substation and my shop plugs read 245 volts .

Just curious what effect ( if any ) this would have on the output of my PM 180C and Syncrowave 200 ?

wesdavidson
03-24-2009, 06:33 PM
We are running a millermatic 180, a dynasty 200 dx, and a miller spectrum 375 plasma all on 208 no problem, as well as a syncrowave, a linde, and a couple of others. As far as I can tell, welders don't care about any difference between 240 "single" 1/1 phase (european style), 240 2/2 phase ( normal home wiring ) or 208 v 2/3 phase power. It gets a little more interesting when you have to hook up a 3 phase machine to 2/2 phase power, (using 2 of the 3 windings) some will, some won't.


I can recommend the millermatic 180, get the spoolgun with it if you can. The Dynasty is pure gold, and the spectrum is worlds better than our old miller plasma.

David R
03-24-2009, 06:39 PM
I have been in shops, or old factories that had true 208 three phase power. That would be 208 between any two legs.

I was working on forklift battery chargers at the time. I would not pick one or two legs off that for anything. Just my exp.

David :)

Broccoli1
03-24-2009, 07:00 PM
Ok- so now that is clear as Mud:drinkup::drinkup:
----------
MM180
Lincoln 180c
Spool Gun Ready
Those 2 fall in to the same class- Continuous Voltage selection

Both are the most $$

--------
HH187- tapped Voltage selection, No Spool Gun

--------
Lincoln SP180T- Welder Supply shop
Lincoln ProMig 180- Lowes
Lincoln 180HD - Home Depot
They all are Spool Gun ready

All 3 of those Lincolns are exactly the same Tapped Voltage machine-different name

:)

wesdavidson
03-24-2009, 07:11 PM
That is what we have - 208 3p 4w .
We use 2 phase (single phase) at another site, we have powered aircraft start cart rectifiers 24v DC 300-400A with either power, just abandon 1/3 of the transformers. not clean, lost some output, but worked. Some DC welders work the same way, not the best system, but sometimes possible. We have also used phase converters with the old lincoln motor generator welding sets, those have all been sold off now. You do with what you have.

The reason for using the term 240 v 2 phase or 2/2 is to separate it from the 200v true single phase some japanese robots and such use. Or the 277v single "phase to ground" voltage of 440V 3phase wiring. which we note as 277 v 1/3P. Just habit.

Most of the older welders have taps for about any power input you can run across.

The Dynasty is great, we have run it on 120, 240, 208, 440, It loves them all. just have some adapter plugs and away you go. Our nightmare is a newby hooking up the spectrum without flipping the 120-240 switch or frying the millermatic 180 with the wrong power. Needless to say, every plug annd outlet is labeled, and is specific to the voltage and amps. Hooray for standards.

lugweld
03-24-2009, 07:17 PM
I have been in shops, or old factories that had true 208 three phase power. That would be 208 between any two legs.

I was working on forklift battery chargers at the time. I would not pick one or two legs off that for anything. Just my exp.

David :)

That's what I said before Mark decided to throw his peanuts in from the gallery.:realmad:

mark8310
03-24-2009, 09:23 PM
Ahhh,,,,,, but luggy ,,,,,, in all your vast experience, have you never noticed,,,, that there are TWO different kinds of three-phase?????? Delta, and Wye. Two different things, for my purposes the Delta is perfect.

mark8310
03-24-2009, 09:32 PM
I have been in shops, or old factories that had true 208 three phase power. That would be 208 between any two legs.

I was working on forklift battery chargers at the time. I would not pick one or two legs off that for anything. Just my exp.

David :)

Yes, David, that is a Wye three-phase. I would agree with you here.

But if you have Delta three phase, AND a neutral going back to the pole (transformer), you can split the lines, 120v, 240 single, or use the 240 three-phase. It is legal, safe, and allowed to do so, it WILL meet code.

You do have to be careful, to never wire the "high leg" into a 120 circuit :rolleyes:

lugweld
03-24-2009, 10:24 PM
Mark,
Again, you fail to read correctly OR
You Assumed that I didn't know the difference. I have wired 3 phase. I have set up packing sheds and saw sheds that had Delta, and balanced leg. One of the things they teach you in Ag engineering/mechanics is the difference.

And again you must have failed to read the OP's post about the issue that he had with having a machine rated for 208 volts and additional voltages that could either be single or 3 phase, but by having the size machine he was considering would make it unlikely that it would be a 3 phase machine and thereby operate off of the balanced leg system by utilzing 2 out of 3 of the legs without regard to a "high" leg issue.

In Delta, the High leg 208V cannot be practically used for anything by itself, so it is senseless to even mention it.

MAC702
03-24-2009, 10:52 PM
...What about 208V or 200V, you ask? As mentioned, that comes about from 3-phase power systems (which you typically do NOT have at your house) where a Delta transformer/wiring is used by the power company and the three different wires/legs are such that two legs are 120V with respect to neutral and the third leg is 208V with respect to neutral while all three legs together are 240V 3-phase power....

The 208V "wild leg" of a Delta set-up is not used on purpose and 208V equipment is not designed for it.

It is designed for the phase-to-phase voltage of a Wye-connected 3-phase transformer with 120V phase-to-neutral.

It can be single phase or three phase. Some machines only need to be single phase, but can be linked to 208V to be most efficient if installed at a facility using this type of transformer, which is common in industrial parks and convention centers.

MAC702
03-24-2009, 10:54 PM
... We use 2 phase (single phase) at another site,...

Using two of the phases to get single-phase power should not be called "2 phase". Two-phase power uses four wires, one pair at a sine wave, and the other at a cosine wave, respectively. It is very rare, if even used anymore.

MAC702
03-24-2009, 11:03 PM
...I'm gonna venture to guess that Lincoln's 208-230 voltage rating means it will run as long as its getting at least 208 volt, and up to 230 volts. Which will work, if i install a 220.

The Miller's 230 volt and Hobart's 230/240 volt?????? i'm confused, Is there a way to wire for 230 volt? whats the difference between the regular 220volt wiring and the 230/240 wiring? yeah, i know the difference is 10/20 volts, but why is it specified that way?

Okay, I skimmed enough of this thread to see both right answers and wrong answers, so I'm just gonna answer this as if no one's addressed it yet.

The Lincoln is linkable between a nominal 208V supply and a nominal 230V supply. "Nominal" means that this is the specified value that represents voltages that are "close enough" and will vary throughout the world.

220-240 Volts are in one class and often represented by the nominal value 230V, though often in the United States, it is represented by 240V because that is the actual target voltage by most distribution transformers and seen by most service entrances. 220V is the actual value in some foreign countries, and is a common misnomer among laymen in the US. 230V is the actual value in many foreign countries in Europe and has recently become the new standard in Australia, though PNG remains at 240V, which was the old Australia standard.

200-208 Volts is another class, represented by 208V nominally. As mentioned, this is common in three-phase wye-connected services.

Equipment marked for one may or may not work well in the other class as they are far enough apart to sometimes cause problems.

Now, I didn't open up a damn book for any of this. I've just been around and know how it is.

MAC702
03-24-2009, 11:06 PM
... with 3-phase 240V Delta you can't get 240V single-phase....

You're right an awful lot, but not this time, sorry. This is 100% wrong.

MAC702
03-24-2009, 11:11 PM
I live about 1/4 mile from a substation and my shop plugs read 245 volts .

Just curious what effect ( if any ) this would have on the output of my PM 180C and Syncrowave 200 ?

I don't know how Canada does its distribution systems, but it would be extremely rare for a substation to determine the service voltage to a residence. Here, there are distribution transformers for every 2-4 houses or so. Do you also have a transformer on a pole near your house, or a big green/grey box on the curb?

But 245V is fine. North American target voltage is 240 V.

mark8310
03-24-2009, 11:51 PM
Mark,
....... OR .. You Assumed that I didn't know the difference.

Well, naturally,,,,,, based on past history, I just assumed you didn't know what you were talking about.

MoonRise
03-25-2009, 01:43 AM
You're right an awful lot, but not this time, sorry. This is 100% wrong.

Yup, I shanked that one. :blush: :dizzy:

Messed up in going around the transformer/phase loops. :dizzy:

3-phase 240V Delta can give you:

- 3-phase 240Vpower
- 120V single-phase to neutral [from the center tap] from two legs
- 240V single-phase from leg-to-leg
- and a wild/high leg at 208V to neutral (which is typically not used)

http://en.wikipedia.org/wiki/High-leg_delta

Better?

MAC702
03-25-2009, 02:42 AM
I finally measured mine after living here for a few months now. Early evening, spring time, and it's 243 Volts. That may make a difference later, so I'll check it in the afternoon in a few months when everybody's air conditioners are on.

silverspring
05-20-2009, 12:11 PM
Most of the older welders have taps for about any power input you can run across.

.

Wes,

I just came into possession of an older (1941) Lincolnweld 150J stick welder. I didn't realize until later that it was not listed as dual 220/240 3-phase, but as only 440. Is it your experience that there are likely taps for 220V (now, 240V) that can be pulled? That would be great, since I don't have 440(480V) available.

thanks

Rich

jcarlisle
06-18-2009, 12:24 AM
Hey folks. I just wanted to thank you for clearing up the questions I had. I had 208 D installed in my house/garage to power the compressor I bought cheaper than dirt($500 for an 88 cfm 3ph comp) but was wondering about voltages b4 I bought a 3ph welder. After reading what yall had to say I went out and checked my voltages and I have 245v between the delta and standard legs. BUT just to check with what yall have said I should be fine buying a 240v 3ph welder right? thanks again.

Jason

transit
06-18-2009, 02:37 PM
I work these problems all the time. Denrep has the best explanation. The confusion comes about because the terms, 220, 230, 240 volts are thrown about loosely. Depending on the application, there may be significant differences.
Lets take a 230 single-phase air conditioner compressor motor. The tag voltage is 230 volts, meaning it is safe to run + or – 10% from the tag voltage or 207 to 253 volts. Now if the A-C is connected to a 208 source it should be safe, no?
As long as the supplied source is more then the low limit of 207 giving a 1-volt cushion.
Now lets look at the REAL world. That 208 source is at the end of a line that runs x number of feet, lets add to that. It’s a hot summer day and the utility goes into Brownout- mode dropping power 3%. Now that 208 is 97% of what it should be, 201.76 volts, the 1-volt cushion is lost. Now the motor wants power for the load it must carry, and the only way that can happen is to draw more amps, [V x A = watts]. Motors are also rated at the maximum current draw and those extra amps will overheat and burn out the compressor.
There are other explanations, however I think most can relate to this one.

pistolnoon
06-19-2009, 04:38 AM
OK so if you want to connect your single phase welder to your box go and look at your breaker box to see if you have two empty sockets for the 115 volt circuits use or one double for a 30 amp 220 volt circuit breaker (their are a number of breaker box types), if their are free breaker spots then get some 3 connector wire around 8 gauge and run it from the box to where you want your welder plug. Two wires connect to the circuit breaker and one to ground.If you do not have any empty slots you have to get a bigger breaker box and transfer all the breakers including the new one.It is very simple and 30 amps is sufficient for home use.All code problems are Ok I think if you have the breaker box in your garage?

Or get a permit and an electrician as you are also transfering your service lines.I was doing some at home wiring a while back and thought I could check the service line differential and it would tell me the voltage on my new DMM, all it took was a blink of the eye and it vaporized the leads and melted the solder in the DMM.
Use an electrician to change the box over if needed.

transit
06-19-2009, 02:54 PM
OK so if you want to connect your single phase welder to your box go and look at your breaker box to see if you have two empty sockets for the 115 volt circuits use or one double for a 30 amp 220 volt circuit breaker (their are a number of breaker box types), if their are free breaker spots then get some 3 connector wire around 8 gauge and run it from the box to where you want your welder plug. Two wires connect to the circuit breaker and one to ground.If you do not have any empty slots you have to get a bigger breaker box and transfer all the breakers including the new one.It is very simple and 30 amps is sufficient for home use.All code problems are Ok I think if you have the breaker box in your garage?

Or get a permit and an electrician as you are also transfering your service lines.I was doing some at home wiring a while back and thought I could check the service line differential and it would tell me the voltage on my new DMM, all it took was a blink of the eye and it vaporized the leads and melted the solder in the DMM.
Use an electrician to change the box over if needed.

NO! NO! NO! You shall not use two 115-volt breakers, meaning two-single pole breakers. For a 230-volt branch you MUST use a two-pole breaker. A two pole breaker has a bar that links both breakers so that if one breaker trips, both breakers trip. If you use two single pole breakers, if one breaker trips the other breaker may still be closed and the circuit is still hot.:nono::nono:

:blob2::nono:If you install a “Larger” panel the total current capacity of the panel shall not be larger then the number of amps that can be delivered by the utility service to the building.

150-amp service to the building shall not have a panel larger then 150 amps.

denrep
06-19-2009, 05:12 PM
...I had 208 D installed in my house/garage...

...I went out and checked my voltages and I have 245v between the delta and standard legs. BUT just to check with what yall have said I should be fine buying a 240v 3ph welder right? thanks again.

Welcome jcarlisle, :waving:

Most likely the power company is providing 208Y/120 OR 240 Delta.

Since your reading 245volts between legs, you probably meant to write that you had a 240volt Delta system installed. In which case 245v between legs would be fine for connecting a welder.

If it is delta, and you don't have a separate transformer for 120v loads, then you probably have a center tapped supply transformer, making it a 4-wire syatem.

With a 208Y/120 installation you would show about 208 volts between legs, and 120v between any leg and neutral.

Well, what kinda welder, and what'cha gonna weld? :)

Good Luck


...I was doing some at home wiring a while back and thought I could check the service line differential and it would tell me the voltage on my new DMM, all it took was a blink of the eye and it vaporized the leads and melted the solder in the DMM....

WWheeeeewwww Better be more careful.

Good Luck

transit
06-19-2009, 07:41 PM
Hey folks. I just wanted to thank you for clearing up the questions I had. I had 208 D installed in my house/garage to power the compressor I bought cheaper than dirt($500 for an 88 cfm 3ph comp) but was wondering about voltages b4 I bought a 3ph welder. After reading what yall had to say I went out and checked my voltages and I have 245v between the delta and standard legs. BUT just to check with what yall have said I should be fine buying a 240v 3ph welder right? thanks again.

Jason

I find it difficult to believe you have 3-phase power installed in your house, and more so if as you clam a 3-phase delta. 3-phase anything is very a-typical for household power.
A 3-phase Y would be found in a commercial/industrial setting, a 3-phase Delta is totally heavy duty industrial and used by utilities for the mane line grid. The transformer on your local power pole would be a 3-phase delta primary with a 3-phase Y secondary. This configuration allows three single-phase feeds 208 and three 120 volt feeds to your house. The relationship for a Y is 1.732, that is 208/ 1.732 = 120. There are many other configurations, 230 or 240 single phase with a center tap for two 115 or 120 volt circuits.

pistolnoon
06-20-2009, 04:55 AM
Transit you misunderstood? I was just describing what a vacant block looks like for a 220 breaker. Why overcomplicate things unnecessarily, if he has the service(single phase), the vacant breaker space, get some wire(proper), a socket(proper),breaker(dual through dual blow) and do the installation and go welding?
Yes?
If it gets any more complicated then you have no other choice but to use certified electrician.I've worked with prime movers, but also do alot of electronic repair and got used to whipping out the DMM to check continuity, and "WWheeeeewwww" is right, I couldn't beleive I did something so careless after I saw my leads disappear.Knew a plant operator with a wicked bubble gum scar across his face, noticed he would always check if motors were overheating or running with the back of his hand.The scar was from a burn from drilling a posthole for a fence with a power auger without getting it marked out, it shocked him once and killed him then the voltage hit him again burned off his ear but revived him.
Nuff said.

transit
06-20-2009, 08:49 AM
Pistolnoon, I can’t imagine what you were doing to smoke a DVM. Most all decent dvm’s have a 2,000 volt AC range, and a 10 Meg input resistance. The only mode that draws a significant current is while directly reading current, connecting the probes across a voltage source would blow the internal fuse. Did someone put a penny in the fuse box?:nono::nono:

joethemechanic
06-20-2009, 11:18 AM
Wow so much bad information.

240 Delta 4 wire will supply 240 3 phase, 240 single phase, 120 single phase and 208 single phase. All 3 windings are 240 V but one is tapped in the center to provide a nuetral and grounding point. they are typlicly found in heavier commercial and light industrial settings.

208 In a wye or (star) has 3 windings. All 3 are identical and are 120V. It will supply 208 3-Phase, 208 single phase, and 120 volt single phase. It is better for applications where you have a lot of 120V single phase loads because you can ballance out the loads and load all 3 phases equally.

Really for heavy industry 240 or 208 volt is too low. You have to run too much copper to keep the I^2R losses down. Not to mention you end up doubling the size of all your motor starters and PLCs if you use 208 0r 240.

Low voltage will not hurt a transformer. low voltage burns up induction motors because when the rotating magnetic field created by the stator weakens, the rotor slip increases (all induction motors have a slip, it is the difference between the actual speed of the rotor, and the sycroness speed of the rotating field). When slip increases there is more relitive motion between the rotating field and the bars of the squerrel cage of the rotor. As a result, rotor current increases. This is what fries the motor.

God God just test you voltage and see what you have. If you have 208 and you want to run a 230 or 240 volt machine put a boost/buck transformer in the line. Wire it up to boost. You can make one out of an old heavy duty battery charger transformer. Or you can buy one probablt from Granger.




When

transit
06-20-2009, 11:34 AM
Joe, a Autotransformer will work to match the power source to the load, however that would be for single phase. The poster mentioned 3-phase and that would be complex = $$$.

joethemechanic
06-20-2009, 11:57 AM
This guy has 3 phase power in his house?

Broccoli1
06-20-2009, 12:24 PM
Could be on a farm

joethemechanic
06-20-2009, 01:25 PM
Yeah maybe a farm. I have seen it in houses but only 2 times in the past 30 some years.

Down in south jersey there used to be a lot of 208 V wye services.

I'm in Philly. We used to have to deal with the remnants of the old TWO PHASE system. Boy was that ever a stupid idea. 1.5 times the amount of copper for 1.43 the amount of power. You had to use a Scott connection to shift the phase.

Or there was a trick to use the Delta connected transformer with the center tap in one winding..

If you connected one phase across the winding with the center tap, and the other phase across the neutral and the high leg you came out with 2 phases 90 degrees apart, but one phase was 240 V and the other 208 V. Not that I ever did anything like that :)