200v Welder Available

[crwsrw]

Hi,

Newbie question...

I want to buy a MIG welder to use in Japan 200v 50Hz. Am I likely to have any issues if I buy a North American machine and try to run it on this voltage/freq?

I see a few 208v/230v machines, but I understand the 208 is three phase. Is 230 too far away from 200 for welding purpose?

Any suggestions for a machine would be greatly appreciated. Budget around $700-800.

Any help appreciated

[MicroZone]

Your best bet is to call the manufacturer of the welder you might be interested in purchasing. They would probably know better than anyone what the requirements are for an electrical system in Japan.

[awright]

First and foremost, discuss your plans with the technical support people at the equipment manufacturer, as suggested above. They probably know exactly the answer. You can probably buy a machine specifically designed for japanese AND U.S. power but it will be more expensive than one designed only for U.S. power because more iron and copper are required in the power transformer (if present) and more capacity is required in the capacitor bank (if present) for safe and adequate operation on 200 volts, 50 Hz and more complex design is required for operation on multiple power sources.

For a machine designed only for 230 volts 60 Hz, you will get reduced welding power on 200 volts 50 Hz if the machine can survive that condition at all. Conversely, a machine designed for operation on 200 volts, 50 Hz will probably operate fine on U.S. power, perhaps requiring only a tap change or, if that is not provided by the manufacturer, an input voltage bucking transformer that you could easily provide. So one option would be to buy a machine in Japan and bring it back with you. That would save shipping one way.

Inverter-based machines are generally much more tolerant of differing input conditions than transformer-based machines because they do not have a main power transformer handling all the input power. How they would cope with the reduced voltage on the energy storage capacitor bank due to the reduced input voltage is a function of the detailed electronic design of the inverter. Same for the increased ripple on the DC bus due to the lower power frequency. Still, I think your best chance of success would be with an inverter machine.

A transformer designed for 60 Hz, 230 volts can be operated at lower frequency if the voltage is reduced in proportion to the frequency change. Unfortunately, this will result in reduced welding power and may also result in insufficient voltage for accessories like fans and control circuitry and wire feed motors unless some adjustment is provided. One problem is that the reduction in frequency is 17%, while the reduction on voltage is only 13%, so a transformer designed with little headroom on saturation of the core will not tolerate the frequency change without a further reduction in supply voltage. Depends a lot on the transformer design, but I suspect that you would be in trouble plugging a U.S. transformer machine directly in to japanese power without an input voltage reduction to about 190 volts. Of course, even though this might avoid saturation and destruction of the main transformer, you will still be losing welding power and voltage to your accessories. The basic problem is that, for economy, a transformer is designed to operate just below the core saturation level for the intended power voltage and frequency. More than the minimum amount of iron and copper to do the job are wasted if the machine is never used on reduced frequency or increased voltage (neglecting efficiency considerations for this discussion). If power frequency is reduced and voltage is not reduced in proportion, core saturation occurs resulting in current surges each half cycle that will either (preferably) pop the overcurrent protection device or (worst-case) burn out the transformer.

Everything considered, since it sounds like you have not purchased a machine yet, I would consider buying an inverter-based machine in Japan and later adapting it to U.S. power, rather than the reverse. Better yet, sell your japanese machine when you come home and buy a U.S. machine.

WARNING! I am not an electrical engineer, just an opinionated hobbyist.

awright

[TIGBOY]

208 is not three phase

[o.c.d.]

Whoever's brand you like the most like stated above I would call the manufacturer before you actually purchase. However, almost all of the "Inverter" type machines have an auto sensing power input circuit (nothing more than a beefy bridge rectifier and filtering caps) along with auto voltage sensing (DC at this point) that will change the frequency of the internal power supply. The older transformer based (extremely heavy) units will probably overheat on 50 HZ after quite a bit of use.

[MAC702]

208 is not three phase
I've yet to see a 208V welding machine that wasn't. You are correct that the voltage itself is not a determiner of how many phases it is, but the fact is that the typical 208V set-up is a wye-connected 3-phase supply.

[crwsrw]

Guys (and gals?) Thanks a heap for all of your replies.

A few details that I didn't put in my first post.

I live in Japan, so the machine will not be coming to the states.

I sent an e-mail to a manufacturer (Lets call them Lincoln for the sake of the discussion) asking about this topic. The reply I got was merely a referal to the Japanese agent. I replied (to the US office) saying thank you very much however I intend buying the welder Stateside, and just want to know whether it is compatible or not. I would prefer not to buy the machine in Japan because...

All the instructions will be in Japanese
All the markings will be in Japanese
I will not be able to get any tech support/after sales support (Don't speak the Lingo well enough to get tech.)
I will get slaughtered on the price.

They replied saying SOL, and cc'd me on the e-mail to the Japan office for them to contact me, and who would have guessed, a week later no contact!

Just as an FYI, I wanted to buy a telescoping 12' ladder. To buy one in Japan is about USD420. To buy EXACTLY the same item in Homedepot - USD190.
Pretty much evertything that one needs hardware wise has the same mark up. It is actually cheaper for me to buy Japanese sockets (Kokon) in Hong Kong than it is in Japan! And they are the original gear, not copy. I go Stateside about twice a month, so it is just the easiest way to get this sort of gear.

Anyway, back to the issue...

The voltage here doesn't vary much. +/- 2v is about the most I have seen (if that makes any difference)

TIGBOY, you mentioned 208 is not 3 phase. Sorry, I am ignorant of most things electrical, and thought I had read that 208 was 3 phase. Would it be fair to say then... that if I could get a 208v 50Hz machine, I am probably not tooo far off what it was designed for.

AWRIGHT, is there an obvious way of telling if a machine is an inverter type vs. a transformer type?


I suppose the other option is to buy a genset or a genset welder. I had been looking at a diesel 6/7.5 kva gen. 120/240v 60Hz.

Appreciate the input from all of you.

[Doolittle]

Why not try esab?

[crwsrw]

Have been having a look at the Japanese Lincoln site, and it seems the PowerMig 215 is single phase. Then went and looked at Lincoln US, and it too shows most of the machines as 1 Phase. Now I am really confused.

Will look at ESAB now. Thanks DOOLITTLE


.....

Just looked at it, and they seeeem to have what is best suited...

SPECIFICATIONS
- Input Voltage – 208/230 Vac, 1ph 50/60 Hz
- Welding Output – 200 Amps @ 20% duty cycle

As I mentioned earlier, is 208v 50Hz close enough to 200v 50 Hz that it is not likely to matter too much?

[jptech]

208 is not three phase


I have 208 3 phase at my shop. ----------john :waving:

[Sandy]

SPECIFICATIONS
- Input Voltage – 208/230 Vac, 1ph 50/60 Hz
- Welding Output – 200 Amps @ 20% duty cycle

As I mentioned earlier, is 208v 50Hz close enough to 200v 50 Hz that it is not likely to matter too much?

Boy that's a tough one. Some guess work and assumptions involved--------or a ton of research. Assuming that the switch set one way would be 208/50hz and the other is 230/60hz is assumption #1.

In the US for instance an machine labeled for 230 is manufactured to operate at a voltage range not quite (but close to) centered around 230 volts, with and acceptable voltage input of a low of 208 volts in to a high of 254 volts in.

So the next assumption is that equipment manufactured in and for other countries would be manufactured to similar guidelines and a labeling of 208 would also mean centered (or close to) around 208 with a nice comfortable limit below 208 and above 208. In that case 200 volts @ 50hz is probably fine as long as you can rely on your local system staying fairly rock solid at or very close to the 200 volts as stated.

In short you are starting with a handicap of of 8 volts below a stated average mean voltage and not much cushion left on the low end.

Sound about right? :)

[awright]

The ESAB with

"SPECIFICATIONS
- Input Voltage – 208/230 Vac, 1ph 50/60 Hz
- Welding Output – 200 Amps @ 20% duty cycle"

will be fine on 200 VAC 50 Hz. The important spec is that it is designed for 50/60 Hz. That means the transformer (if it has one) will not saturate merely from being connected to 50 Hz. It probably also means they provided a little more capacitance (if present) to minimize ripple on 50 Hz power. The 8 volt deficient input voltage could very slightly limit your top end power, but you would probably never notice the difference. Is that range important for your intended usage anyway?

You can generally tell if a machine is an inverter or transformer machine by the bragging on the front panel or in the literature if it is an inverter and by the fact that an inverter is dramatically lower in weight than the equivalent transformer machine. If in doubt, look at the weight spec or try to pick up or move the machine by pushing on it. Also, if you look under the covers, you will not see a large power transformer in an inverter machine (although you might see inductors that look like small power transformers and a small inverter transformer).

208 volts is derived directly from 120 volt three-phase wye-connected power by connecting to two legs of the wye. This is a common short-cut for operating single-phase equipment requiring higher power than common 120 volt circuits can supply in a facility with 120 volt 3-phase wye power. Single-phase equipment connected to two legs of 3-phase power sees only single-phase power, not some weird "phase." However, the center of the wye will not be usable as a neutral for such equipment because that is where you will see the effect of being connected to two legs of three phase power.

When a facility uses this type of power for some higher power equiipment, the electricians must attempt to roughly balance all the single-phase loads by distributing them roughly equally between the three phases. This is primarily to load all legs of the power system transformer equally.

Manufacturers sometimes make their single-phase equipment capable of using 208 volts to accommodate users having only three-phase power distribution in their facilities. If you only have 120 volt three-phase power you would have to supply an expensive transformer to get 230 volt power for conventional equipment unable to operate off 208 volts. Conversely, it is a simple matter for the equipment manufacturer to provide the capability to use 208 volts by providing taps on their main transformer. 208 volts single-phase can also be derived from 120 volt three-phase delta connected power, but in that case you have to have a center tap on one leg of the delta. That can be an added expense.

To summarize, 208 volt loads can be either single or three-phase, but you are normally only going to get 208 volts from a three-phase distribution system.

awright

[TIGBOY]

Well I Guess I Should Triple Check Things Before I Run My Mouth.ive Never Personally Had A 208 Three Phase But Thats Just Me.i Appologize Fo The False Info.