3 Phase Power

[ProColorGraphics]

Has anyone here ever dealt with 3phase converters? Looking at a flatbed cutter, but need to have 3phase power. Will probably need to go the converter route, so looking specifically for info on them.

Does anyone have personal experience with 3phase converters?

 

[Christian @ 2CT Media]

Definitely find the highest efficiency one, they waste a lot of power.

 

[Gino]

We were on it, but had it removed some years ago. 3 phase is a very effecient form of electricity, but it's really only good, if you have a lotta machinery on it. Ours ran on demand. So, the electric company monitors your usage in 15 minute increments for your entire month and when your usage was the highest of the month, they base your monthly bill on that. What happens is, if you come into your shop in the morning and turn on all the computers, printers, cutters lights, air conditioners and anything else, that could easily be your heaviest demand, thus basing that months cost on that alone. Has nothing to do with turning the 3 phase unit on or not. Therefore, turn a few things on over a period of 1/2 hour or 45 minutes according to how many things you have plugged in.

Anyway, that's how it worked for us. Don't they make a unit which will work on 220 ??

 

[particleman]

We used a seimens variable frequency drive (vfd). Our electrician explained these were more efficient than older tech converters. So you might look into that.

 

[equippaint]

Its not true that phase converters waste a lot of power. The motor is always running with no load as it is only used to provide the 3rd leg. For some reason people float this idea around but have never actually checked into it. Look at a spec sheet or call a manufacturer and speak with an engineer. Ours runs all day 7-7 and was calculated to cost about $20/mo. We have seen no increase in our power bill since we moved from a place that had 3 phase in it.
You need one that is double your needed hp so a 10hp compressor will use a 20hp converter. Get a rotary too not a static. Prices are good on ebay.

 

[davison]

We use a toshiba variable frequency inverter. Cost us about $300 used. All you need is a 240 volt line single phase line, run it to the inverter. Very easy to use.

 

[ProPDF]

Check out American Rotary ADX20 or larger to run your pumps. Depending on your table pump requirements FPZ Pumps have some good single phase pumps if you don't want to deal with the converter. Just because you get a strong pump doesn't always mean more suction, sometimes it means damage to air channels actually so be careful.

 

[ProColorGraphics]

We use a toshiba variable frequency inverter. Cost us about $300 used. All you need is a 240 volt line single phase line, run it to the inverter. Very easy to use. View attachment 133808

What do you run with that?

 

[Christian @ 2CT Media]

Its not true that phase converters waste a lot of power. The motor is always running with no load as it is only used to provide the 3rd leg. For some reason people float this idea around but have never actually checked into it. Look at a spec sheet or call a manufacturer and speak with an engineer. Ours runs all day 7-7 and was calculated to cost about $20/mo. We have seen no increase in our power bill since we moved from a place that had 3 phase in it.
You need one that is double your needed hp so a 10hp compressor will use a 20hp converter. Get a rotary too not a static. Prices are good on ebay.

I can tell you for a fact that they do waste a lot of power. We had a single to 3 phase converter years ago because we didnt have room in our panel and we used significantly more power than when we rewired it directly after installing a subpanel for other equipment. It was a 3 to 1 draw vs straight 3 phase for that one piece of equipment.

 

[equippaint]

I can tell you for a fact that they do waste a lot of power. We had a single to 3 phase converter years ago because we didnt have room in our panel and we used significantly more power than when we rewired it directly after installing a subpanel for other equipment. It was a 3 to 1 draw vs straight 3 phase for that one piece of equipment.

Then you measured something wrong because its just not possible. Take a few minutes to understand exactly how it works and the difference with 1 and 3 phase and this would make more sense. There is some loss but it is not significant. For a 20hp adx20 as mentioned above, it is .3 KW so at .15 per kw/hr its $750 per year. Rather than argue with me and give people bad info just call American Rotary 888-357-5920 and ask them. We used to buy and sell compressors from industrial auctions and dealt with this quite a few times. We also installed some of these with phase converters with a friend of mine that is an electrical contractor. You have to have load calculations which included the converter to size the breakers, sub panels and wiring properly.

 

[Christian @ 2CT Media]

Exactly my point, there are many different types of phase converters, Some use more power than others which is why I said find the highest efficiency one.
With my unit we were consuming 17,000 KW/Month after going to a true 3 phase we are only consuming 11,000KW/Month. We are busier now with more equipment and no other equipment changes like HVAC have occurred. Our Phase converter was a rotary style and was a 60amp output

 

[ProColorGraphics]

I have a friend who runs a large machine shop and has used several types/brands. He highly recommended a digital converter, specifically Phase Technologies. They say they are 97% efficient, don't require doubling the HP size, don't create a high leg (all 3 power legs maintain the same voltage), maintain constant voltage during loads, etc. They look very nice, but come with a VERY nice price tag too. haha. Just trying to determine if it's worth almost twice the money.

 

[equippaint]

Exactly my point, there are many different types of phase converters, Some use more power than others which is why I said find the highest efficiency one.
With my unit we were consuming 17,000 KW/Month after going to a true 3 phase we are only consuming 11,000KW/Month. We are busier now with more equipment and no other equipment changes like HVAC have occurred. Our Phase converter was a rotary style and was a 60amp output

No matter how many times you say it I will guarantee you that it was not your phase converter. Is 6000kw/month even possible on a 60 amp breaker in a months time? I think your neighbor was skimming your power for a grow house or something.
This may be an old wives tale so dont take it as the gospel but I was told a couple times that low 3 ph power consumption sometimes wasnt picked up well by your meter. This has never been my experience but Im just throwing it out there. If it was true, then this could explain it.
There are 2 basic kinds of phase converters and virtually all massed produced converters will be similar in efficiency. As far as I know is that the problems come in more with static converters not having good power balance which can burn up motors and cause them to not run at peak power.

 

[equippaint]

I have a friend who runs a large machine shop and has used several types/brands. He highly recommended a digital converter, specifically Phase Technologies. They say they are 97% efficient, don't require doubling the HP size, don't create a high leg (all 3 power legs maintain the same voltage), maintain constant voltage during loads, etc. They look very nice, but come with a VERY nice price tag too. haha. Just trying to determine if it's worth almost twice the money.

Id go with a standard rotary phase converter. They are very basic, its a box with some capacitors and a 3 phase motor. Stuff you can diagnose and replace yourself down the road. We've used american rotary in the past and have one at my shop, I put their number above and they have always been helpful with us.

 

[ProColorGraphics]

Id go with a standard rotary phase converter. They are very basic, its a box with some capacitors and a 3 phase motor. Stuff you can diagnose and replace yourself down the road. We've used american rotary in the past and have one at my shop, I put their number above and they have always been helpful with us.

That's my debate now. Their ADX20 is what I was recommended. I even chatted with another shop who has the identical setup with the ADX20. I also have to run my through a transformer after the converter to get the 208 WYE voltage (with a neutral) I need.

 

[equippaint]

That's my debate now. Their ADX20 is what I was recommended. I even chatted with another shop who has the identical setup with the ADX20. I also have to run my through a transformer after the converter to get the 208 WYE voltage (with a neutral) I need.

This is a bit over my head but I guess you need the 208 to pull 120v for control voltage as just the motors will be 208-230 3ph? Our shop compressor is setup like this and we have an ADX20 with no transformer. It has 120 controls and drier and the compressor is 208 3ph. My friend hooked this all up and I don't recall exactly what we did back then.

 

[ProColorGraphics]

This is a bit over my head but I guess you need the 208 to pull 120v for control voltage as just the motors will be 208-230 3ph? Our shop compressor is setup like this and we have an ADX20 with no transformer. It has 120 controls and drier and the compressor is 208 3ph. My friend hooked this all up and I don't recall exactly what we did back then.

Yep. I have 240v right now and whatever you put into the converter, you get out. Would need to do the transformer after the converter to get the 208v with the neutral the machine needs.

 

[equippaint]

Yep. I have 240v right now and whatever you put into the converter, you get out. Would need to do the transformer after the converter to get the 208v with the neutral the machine needs.

I dont think that you will need a transformer and would call back american rotary or an electrician to check. They are saying its 208 with a neutral (208 WYE) because you need to catch 120 1ph for the controls and if you have a 230/460 setup this wont work straight out of the box as far as I know. The motor will be fine on 230-240 3 phase also. We definitely did not put in any transformer here and our compressor requires 208-230 and 120v1ph

 

[ProColorGraphics]

I dont think that you will need a transformer and would call back american rotary or an electrician to check. They are saying its 208 with a neutral (208 WYE) because you need to catch 120 1ph for the controls and if you have a 230/460 setup this wont work straight out of the box as far as I know. The motor will be fine on 230-240 3 phase also. We definitely did not put in any transformer here and our compressor requires 208-230 and 120v1ph

It was the guy at American Rotary who told me I would a transformer to get the 208 wye setup with a neutral. I could do a buck/boost transformer on the single phase side to get to 208v, but would still need to run a neutral over. For a few hundred more, I am going to do it on the 3phase side, then I don't have to worry about that or the high leg either.

I am guessing it needs the 120v for the vacuum and/or controls.