Question: US 220 vs Aussie 220

Bought a DoAll blade welder from Gunner last year, and finally getting around to restoring it. Wrote DoAll asking about parts and an electrical question, got a reply back in less than an hour! Learned it was made in

He had no answer on the electrical question though. I'd asked someone, somewhere, about just using one leg of the 220 for 110, like we do here, to run tools with brush motors. He informed me that their 220 IS 220, each leg, where ours is combined from two legs of 110. A step down transformer will take care of that issue, I've already left a decent sized one with my wife. But for the welder...

So dumb question for the electron challenged, can I just hook this up to their 220 and run it, or will that smoke it? If the latter, what are my options?

This might also sorta apply to my Grainger hand held spot welder. It's

Seeing as I'm going to be an hour drive from anywhere that I could buy blades, I'm really wanting to take this with me! Might even be able to make a little side money welding blades for other folks.

Jon

Our 220 *is* 220, we just center tap the transformer to provide a neutral in the middle.

If it's a 220 welder, their 220 and our 220 is the same as far as voltage is concerned. It's 50HZ power vs. our 60HZ power so verify that the welder can handle 50HZ.

I doubt it can be rewired for 220.

Perhaps, but better to see if you can get the 220 version of the welder.

Be careful what you wish for - I had to wear corrective glasses in the

Good Luck! Rich

You didn't say what the machine expects. If the machine wants 110, then

If the machine is strictly 110, then if there aren't voltage options for it (like a terminal strip, or swappable leads), then yes, unfortunately your best option is a step-down, albeit an "autotransformer" would be cheaper than a full transformer.

And do NOT, under ANY circumstances, think that putting a diode in series with the line will cut 220 down to 110 - you'll get pulsating DC (which can smoke an induction motor) at an effective 150 V or so, which will smoke your welder. (I know - you'd think that if the current is only flowing half the time, that you'd get only half the power, but the electronics gurun at sci.electronics.design taught me about RMS (root-mean-square), or effective voltage; I didn't believe them until I did it on a spreadsheet. I was shocked!

Crap! Where should I have closed that paren?

Good Luck! Rich

In Australia (and other places that use 220) one leg is neutral (ie has a potential that is very close to ground/earth) and one leg is hot. This is just like in North America, except that in NA, the hot leg is at 110 whereas in OZ it is 240.

In North America, 220 is made from TWO HOTs and neither leg is neutral.

Many types of appliances are designed so that hot and neutral can't be mixed up, and may have safety features that depend on the neutral being, in fact, neutral. This is just as true of Australian appliances as it is of North American or wherever.

Now you go putting two hots into an appliance designed for neutral plus hot -- well, it may work fine. Or it might electrocute the user. Your consulting electrical engineer would not sign off on this.

Have fun.

____________________________________________________________________ Gardner Buchanan gbuchana(a)teksavvy(dot)com FreeBSD: Where you want to go. Today.

In Australia and other 50hz countries the distribution is usually 3 phase 230/400 volts nominal but as it was 240 volts in years gone by many areas still have 240 or more delivered (it is rarely below 240 at my house). This is active to neutral and neutral is grounded at the building entry. For higher loads the three phases can be used with 400 between them. No metion has been made of the power required by this welder and although the duty cycle may be short any transformer will need to cope with the high start current. Auto transformers are frowned upon and, I think, not allowed in some cases because it is possible to have the 110 volts at the high end and not at the neutral end if the wiring is not correct.

Pehaps Gunner could tell us what the power requirements might be??

Welders aren't exactly "appliances", and they don't have two conductor plugs. We are also talking about applying OZ power to US appliances, not the other way around, so they are built to accept two non-grounded power legs and a separate ground connection.

No issue.

No issue.

Issue since OZ power is 50 Hz. For a short duty cycle item like a blade welder you will *probably* be ok. If it was a continuous duty item you may have a problem. Obviously motor based items will run at a different speed on 50 Hz vs. 60 Hz.

No issue.

Yes, .5 continuous would make sense for the annealing cycle.

You're getting the definitive answer. 220V is 220V whether in AU or US, the issue you will face is the frequency difference of 50 Hz vs. 60 Hz. Many items will be rated 50/60 Hz and thus have no issue, while others may have issues. Transformers for 60 Hz are different from those for 50 Hz and as others have noted, might saturate and overheat in continuous use on 50 Hz. For short duty cycle items like a blade welder they will probably do ok, for continuous / extended duty cycle items like an arc welder there could be issues if the welder doesn't have a 50/60 rating.

A local electrician won't be in any better position to give you accurate information that RCM can. The equipment manufacturer is the only one that can tell you with any certainty if their 60 Hz rated product can operate without issues on 50 Hz power.

You could do that as well.

MY OEM spec eyeballs. had 20/13 vision at one time. Just barely passed vision test for my license renewal a few months ago...

Jon

Ok, thought I'd spelled it out, but didn't. Here's the blade welder specs:

Sounds like I'd best find a local electrician that can give me a definitive answer. Or weld up a life time supply of blades before I go...

Jon

I only have a couple induction motor items, like my Baldor carbide grinder. I rarely ever run it more than a minute or two, so foresee no problem there. If it ever does die from overheating, I'll hack-n-whack the motor and case to allow belt drive from an external 50Hz motor. My bench grinder, I'll use until it dies, then replace w/local flavor.

Ok, thank you. I'm loosely aware of the 50/60Hz issue in terms of heating, but my gut feeling was that for the second it takes to actually weld a blade, I wouldn't have trouble. But when Magic Smoke is involved, I don't like to assume. I doubt I'd ever be production-line welding blades, but will take care to make sure it doesn't overheat.

Actually they couldn't, which is why I came here. I'll have to pay attention to the blade grinder, might have to retrofit a 50Hz motor there, or simply grind blades with something else.

Jon

I would not consider that to be a problem. The actual weld cycle is on the order of 0.1 second if not shorter, (I've never hooked up a 'scope to actually *measure* it. :-)

Annealing takes a few seconds -- but at somewhat lower current with shorter (perhaps 1 second) pulses spaced out as you cool it.

The motor *might* draw a bit more current, but mostly it will run slower by a factor of 5/6 (I believe it to be an induction motor, not a brushed motor). The cure for the slower really involves a slightly larger diameter wheel (and thus modifications to the guard) if you really want the same speed. But for the application, you can take a few more seconds grinding. Just don't plan to weld a couple of dozen blades and then grind them all in a single run. If you weld one, then grind it, and weld the next etc, you should be fine as long as you don't leave the grinder running while you grind the next blade.

As for making up a lifetime supply of blades before moving -- consider that the bulk is a lot greater than a spool of blade stock. And do you really know how many blades you will need in your lifetime?

Also -- the bandsaw will run slower, too -- though if it is a variable-speed one, you should be fine.

Good Luck, DoN.

Oh, I was really kidding on that one... Yeah, plan to take several 100' rolls in varying pitches.

Plan for this is a 1/2hp 3ph motor w/inverter I can run from single phase 220.

Jon

There you are. If it's 220, it's 220, albeit the 50 Hz/60 Hz thing might be of concern, depending on what's drawing the power. Heating element, no worries. Induction Motor, it will run at 5/6 rated RPM, so might be a concern.

Hope This Helps! Rich

60 Hz typically requires a finer (thinner) lamination to decrease the Eddy current losses and heating incurred in the lamination core.

North America (Don't know about Mexico) never had 220v. It was and always will be 240 Volts. 110, 115, 117, 220, 230, 550, and 575 volts are all somebody's guess, usually from another continent.

----------------------

Bought a DoAll blade welder from Gunner last year, and finally getting around to restoring it. Wrote DoAll asking about parts and an electrical question, got a reply back in less than an hour! Learned it was made in

He had no answer on the electrical question though. I'd asked someone, somewhere, about just using one leg of the 220 for 110, like we do here, to run tools with brush motors. He informed me that their 220 IS 220, each leg, where ours is combined from two legs of 110. A step down transformer will take care of that issue, I've already left a decent sized one with my wife. But for the welder...

So dumb question for the electron challenged, can I just hook this up to their 220 and run it, or will that smoke it? If the latter, what are my options?

This might also sorta apply to my Grainger hand held spot welder. It's

Seeing as I'm going to be an hour drive from anywhere that I could buy blades, I'm really wanting to take this with me! Might even be able to make a little side money welding blades for other folks.

Jon

My understanding is that you can run 50hz transformers on 60hz without any problems - the higher the frequency the less iron required.

And as far as the voltage is concerned, 115/230 has been a standard voltage in many areas of North America over the years. 117/235 may not have been an official standard - but was also common in many areas.

Yes. In the late 40s to early 50s the Ontario 25Hz system was converted to

I believe you are correct about 50 to 60Hz transformer usage as the iron size would be way oversized. It is different going the other way (60 to 50) Typically the laminations were not much different to cause any excess heating losses in the cores. It`s been a while for me on this subject. The winding ratios determine the voltage in:out ratios and the current ratings of the conductors don`t change.

The standard N. American voltage spec is 120, 240, 600 (Some parts of Canada, not familiar with 440-480 though) + or - 10% at the customer`s panel entrance. AFAIK it has always been that but much confusion has happened over the years.

The only place I have heard of 135v is on rural light bulbs so they run cooler and the filaments last a long time and are not as critical with surges. We may be confusing appliance and device voltage ratings with system supply specs mandated by governing bodies. Sometimes the voltages are reduced to express what people think are at the receiving end. eg. 550v

Network system supplies used in apartments and downtown Kit. run 125, 216 in order to satisfy the specs using 2 out of 3 legs on a 3ph 4w system into residences to reduce the conductor size to deliver it to multiple units in close proximity.

------------------ My understanding is that you can run 50hz transformers on 60hz without any problems - the higher the frequency the less iron required.

And as far as the voltage is concerned, 115/230 has been a standard voltage in many areas of North America over the years. 117/235 may not have been an official standard - but was also common in many areas.

Hmm, ok, maybe I'd be better off sourcing these transformers down there. I'll browse eBay.au and ask around. Maybe if I can find some used ones they won't be as expensive as I fear. Bit gun-shy over prices, rather shocking to see a 30 pack of Pepsi on sale for $26. But maybe these won't be as dear as I was thinking.

Jon

Idiot. 60 Hz motors will overheat when used on 50 Hz. Transformers will saturate, and draw more current.