Learn something every day - who knew there was 460-volt single phase?

[Packard V8]

A machinery broker friend bought a complete automotive machine shop and for helping him load out, we get the scraps.

There was an older Miller Dialarc HF welder, labled 460-volt input. The broker didn't want to pay anything for it and the building owner said, "Well, who's got 460-volt three-phase? Just toss it in the dumpster."

Since it had a water-cooled Tig torch and a set of stick leads, we said, "We'll take it home for the parts." When we got it home, I looked on the Miller website and there was a pdf manual. I opened it, read the specs and found this machine is single phase and can easily be configured to operate on 230-volt input. From what I've read, it's a solid old welder and was working fine when it had a near-death experience.

We cleaned it up, changed the jumpers to 230-volt input and will report when we're making sparks.

jack vines

 

[Bert_]

It's a single phase machine that could be ran on two legs of a normal 3ph service.

460v single phase service is out there. I've installed two. Most recent was installed on a new grain site to power a 75hp motor through a 125hp vfd. 125hp vfd was not available in 230v

 

[micromind]

A machinery broker friend bought a complete automotive machine shop and for helping him load out, we get the scraps.

There was an older Miller Dialarc HF welder, labled 460-volt input. The broker didn't want to pay anything for it and the building owner said, "Well, who's got 460-volt three-phase? Just toss it in the dumpster."

Since it had a water-cooled Tig torch and a set of stick leads, we said, "We'll take it home for the parts." When we got it home, I looked on the Miller website and there was a pdf manual. I opened it, read the specs and found this machine is single phase and can easily be configured to operate on 230-volt input. From what I've read, it's a solid old welder and was working fine when it had a near-death experience.

We cleaned it up, changed the jumpers to 230-volt input and will report when we're making sparks.

jack vines

I've hooked up a ton of those, both voltages.

I wonder how much perfectly good machinery gets thrown out because the owner is too stupid to know it can be used elsewhere.

 

[W-Cummins]

All of the AC tig transformer machines I have seen are single phase. I rewired my syncrowave 351 to run at 480V as I don't have 240v in my shop.

Was the motor load VFD just 2 legs of 480V three phase? Or some 480V to ground system?

 

[Bert_]

All of the AC tig transformer machines I have seen are single phase. I rewired my syncrowave 351 to run at 480V as I don't have 240v in my shop.

Was the motor load VFD just 2 legs of 480V three phase? Or some 480V to ground system?

They set a 240/480 1phase tub.

3 phase primary was several miles away. Think the co-op quoted 3 or $400,000 to rebuild primary.

 

[T444e]

I wasn't either until I had a job that had 460V/1ph electric unit heaters scheduled. Looked up the basis of design heaters and they were offered in 460V/1ph. Learned something that day. Mind you I'm a mechanical contractor, not electrical. There was 3 phase power on site.

 

[Graham08]

My Lincoln TIG is the same way...it can be set up for either 230V or 460V single phase by connecting the bus differently in the machine. I've never been in a building with 460 single phase.

 

[dr_clyde]

A friend of mine has 480v single phase at his property. AFAIK all the power company needs to do is set a different transformer.

The extra voltage allowed him to run phase converters to run his 3 phase machinery without running huge wires to handle the massive amp loads of lower voltages.

Pretty much every AC/DC transformer style welder I've ever seen was single phase only. If you have 480v 3 phase service, you simply omit a phase on the input power.

I'm not sure what it is about transformer/rectifier welders buy AC/DC machines and 3 phase power don't get along. DC only machines are easy to come by on 3 phase, but not AC/DC machines like the Dialarc or Syncrowave.

 

[Bert_]

If it can do AC welding it can only be single phase. What would you do with the third welding lead?

DC is easy because you rectify it.

 

[nh_yota]

It's a single phase machine that could be ran on two legs of a normal 3ph service.

460v single phase service is out there. I've installed two. Most recent was installed on a new grain site to power a 75hp motor through a 125hp vfd. 125hp vfd was not available in 230v

Is that because there may only be a single phase primary out in farm country?

 

[dr_clyde]

If it can do AC welding it can only be single phase. What would you do with the third welding lead?

DC is easy because you rectify it.

Yeah that makes sense.

Inverter machines run off 3 phase and output AC just fine, but I suspect the inverter can make use of that third leg in a way a simple transformer can't.

 

[Bert_]

Yeah that makes sense.

Inverter machines run off 3 phase and output AC just fine, but I suspect the inverter can make use of that third leg in a way a simple transformer can't.

Inverters are DC in the middle. If it can output AC, it's AC>DC>AC

 

[Bert_]

Is that because there may only be a single phase primary out in farm country?

Sometimes yes. You can get three phase usually but it depends on how much you want to spend. That situation the cost for the utility to rebuild their poles for the extra wires was 3 or $400,000. They pretty much push the entire cost on the customer since on farm stuff only has heavy use for about 1 month out of the year. They won't recoup the cost in increased revenue.

My understanding is 480 single phase is pretty common also in areas where they irrigate.