• Watch Out for Scammers!

    We've now added a color code for all accounts. Orange accounts are new members, Blue are full members, and Green are Supporters. If you get a message about a sale from an orange account, make sure you pay attention before sending any money!

Gunsmithing 40hp Rotary Phase Converter Startup

300sniper

300sniper

Gunny Sergeant
Full Member
Minuteman
Jan 17, 2005
3,438
23
Greenwood, Ca
I was expecting this to be more dramatic due to the physical size of it but it is pretty uneventful. The cell phone video makes it sound louder than it really is. You can defiantly hear it running but you can stand next to it and easily have a normal volume conversation. If you are in the market for a RPC, I highly recommend American Rotary. They have great customer service and so far, a great product.





American Rotary 40hp AD Phase Converter Startup - YouTube
 
skkeeter said:
How much did that contraption cost you? Im planning on upgrading my lathe to a 3 phase in the next few months..
Click to expand...

A little over $3k for the RPC, about $1200 wire/disconect/parts, couple 30 packs of coors light and about 10lbs of tri-tip for labor.

It will be MUCH less for a typical manual machine.

Edit: how are you "upgrading" by going to 3ph? Maybe 3ph motor and a VFD would be an upgrade but shouldn't need a RPC for that
 
Last edited:
300sniper said:
A little over $3k for the RPC, about $1200 wire/disconect/parts, couple 30 packs of coors light and about 10lbs of tri-tip for labor.

It will be MUCH less for a typical manual machine.

Edit: how are you "upgrading" by going to 3ph? Maybe 3ph motor and a VFD would be an upgrade but shouldn't need a RPC for that
Click to expand...

Yes, my statement was a bit confusing! I'm currently on a smaller lathe running 220. I'll be buying a new lathe (Possibly a G0509G). This is all new to me (electrical), so I'm assuming your running something much larger?
 
skkeeter said:
Yes, my statement was a bit confusing! I'm currently on a smaller lathe running 220. I'll be buying a new lathe (Possibly a G0509G). This is all new to me (electrical), so I'm assuming your running something much larger?
Click to expand...

Now that I reread it, it makes more sense.

For that, you'd probably want the 7.5hp phase converter. You may be able to get away with a 5hp but pretty risky. NEC requires the single phase feeder wires to be rated at 250% of the 3 phase load. For the machine you listed, you would need wire up to the converter rated for at least 44 amps. I'd go with #8 wire. The continuous single phase load would be about 29 amps. Your wire is rated for 50 amps, so using a 50 amp breaker would be fine.

The converter will probably be around $800. Your wire and parts will be MUCH cheaper than mine, but if you are paying for an electrician, you may catch up to me on the install costs.

EDIT: I am not an electrician. I do stay at a Holliday Inn Express once in a while when I can find one with good free beer happy hour and I've only almost killed myself a few times with electricity. Seek a professional's help to verify the numbers I posted above.
 
Last edited:
#8 should be plenty for 44 amps at a reasonable distance. I run #/6 pulling 70 amps continuous with no problems at 175 feet. Type SOOJW is usually best for me.
 
Last edited:
300sniper said:
Now that I reread it, it makes more sense.

For that, you'd probably want the 7.5hp phase converter. You may be able to get away with a 5hp but pretty risky. NEC requires the single phase feeder wires to be rated at 250% of the 3 phase load. For the machine you listed, you would need wire up to the converter rated for at least 44 amps. I'd go with #8 wire. The continuous single phase load would be about 29 amps. Your wire is rated for 50 amps, so using a 50 amp breaker would be fine.

The converter will probably be around $800. Your wire and parts will be MUCH cheaper than mine, but if you are paying for an electrician, you may catch up to me on the install costs.

EDIT: I am not an electrician. I do stay at a Holliday Inn Express once in a while when I can find one with good free beer happy hour and I've only almost killed myself a few times with electricity. Seek a professional's help to verify the numbers I posted above.
Click to expand...

I know a little bit more about electricity than building rifles, so I can say that the above is GTG. You can do the install your self, but you must respect electricity very much because it's not prejudice nor biased. It will flat out kill you if you mess up. It only takes 1/10th of an amp to stop your heart. I've been very lucky considering how many times I've been bit by secondary voltage (under 600 volts). The American Rotary systems come with good wiring diagrams that you can follow. I have a 7.5 HP unit that ran my 5 HP lathe and two HP mill just fine, so you will be GTG with that.
 
BTW, it's always easier and usually not a very expensive investment to overrate your wire size when the run is short. In other words, if the amperage draw calls for # 8 wire, you can go # 6.
 
Are the American Rotary Converters idler motors with a fancier control or does the motor have separate windings for the 1 phase input and 3 phase output?
 
STR said:
BTW, it's always easier and usually not a very expensive investment to overrate your wire size when the run is short. In other words, if the amperage draw calls for # 8 wire, you can go # 6.
Click to expand...

Yes. I'm using 4/0 al SER cable to my disconect for a couple reasons.
 
Any reason you didn't go with PhasePerfect for that amount coin?
One side note, if you're running a late model CNC with it, you might have to invest in a buck/boost transformer to get the voltages within mfr. spec.
 
300sniper said:
Yes. I'm using 4/0 al SER cable to my disconect for a couple reasons.
Click to expand...

You'll be happy you did.

I used to install these critters on machinery I sold/installed when it went out into the boondocks. Rotary converter's don't like to be voltage starved. People often overlook the fact that there's a big difference between the full load amperage on a motor and the "inrush current" when it starts up.

Nice thing about Rotary's versus Static Phase Converters is that you only need one. If the converter is rated for the largest size motor in the shop you can run several machines without having to add more converters. They are pricey though.
 
CS223 said:
Any reason you didn't go with PhasePerfect for that amount coin?
One side note, if you're running a late model CNC with it, you might have to invest in a buck/boost transformer to get the voltages within mfr. spec.
Click to expand...


I am already seriously pushing my budget. The Phase Perfect would have been about $2k more.

I am looking into a buck transformer right now. My tech thinks it will probably be fine for the amount I will be using it but long term is hard on the spindle motor. I am within the control's voltage specs, which is where everything starts out. But looking at the spindle motor, I am over that by a little bit.
 
Last edited:
300sniper said:
I am looking into a buck transformer right now. My tech thinks it will probably be fine for the amount I will be using it but long term is hard on the spindle motor. I am within the control's voltage specs, which is where everything starts out. But looking at the spindle motor, I am over that by a little bit.
Click to expand...

One thing to be real cautious of when using a rotary converter and that's to make sure the machines you run off it don't have the control voltage connections made to the "generated third wire". Make sure they are connected only to the "pass through" line connections. That "wild leg" can have some nasty voltage fluctuations and should never be used for a Hot/Neutral connection.
 
I have been using a 10hp to run my 5hp lathe. They are very quite and deliver solid voltage according to my Fluke.
The control box was very easy to wire.


R
 
Deadshot2 said:
One thing to be real cautious of when using a rotary converter and that's to make sure the machines you run off it don't have the control voltage connections made to the "generated third wire". Make sure they are connected only to the "pass through" line connections. That "wild leg" can have some nasty voltage fluctuations and should never be used for a Hot/Neutral connection.
Click to expand...

Very true.
 
I built my own converter with the help of our local electrical wizards. A pile of giant capacitors, a starter capacitor or two, some switches to turn it off or on and a contactor for the switch to run, a switch that cuts out the switches when the motor starts running (keeps the manual switches from carrying power when running) and a pile of wire and boxes to put it all in. I used a 15HP 3 phase motor and it works quite well. Cost was about $300 plus my labor to assemble. I run a lathe that has a 7.5HP motor and a mill with a 3.5HP motor. Sometimes other stuff is run as well but not often. The wizards told me that every machine in line that you start up helps with power production so even with the 15HP converter I can run a lot more than 15HP total in motors. I can run both the 7.5HP lathe and the 3.5HP Mill and the 5HP chop saw and not exceed the capability. The unit should be sized to start the largest single motor you need to run....

Much better than the crackerbox starter setups. Makes real power and allows full power from your motors.

Frank
 
Converters lose 20% efficiancy so your setup will never be running 100%. It will run but its not 100%. And thru time its not the greatest thing for interal motor wireing degredation.
 
EasyGravy said:
Maintaining voltages on those three phases is also important because it thru time will do wonders to your machine inerds. Gotta stay in that .05%
Click to expand...

Funny you say that. My most sensitive motor cut out at 2% variance. I was surprised when I had a conversation with the local power company in what kind of variance they are allowed on the line... It will scare most people!
 
300sniper, that 4/0 ain't no joke! That's the size of some of my main leads coming out of my 450Kw generator.
 
Yes. Thats usually why sensative loads are ran thru transfer switches supported by UPS and generators. The ups acts as a duel function. Its a power filter and a ups."clean power". In case of power loss, ups holds the load till generator sincs.
 
Biggest wire I've personally worked with was parallel runs of 750mcm. I use to do a ton of work with bare copper 250mcm for ground grids.

We did a transformer and switchgear swap on a 4160v system last year. That was interesting because of what/who we had to shut down to do it and our short maintenance window to do it in.

The sensitive loads I deal with now are all DC and run off a large battery bank constantly being charged by a bank of rectifiers. The sensitive equipment never knows when there is a power failure.
 
Last edited:
300sniper - I used to run a power plant with many gas turbines, each generator was rated at 75-100 Mw, put power out from generator leads at 13,800 volts, three phase, to a short bus duct system and air circuit breaker. From the breaker cabinet, went underground in 12 cables, 4 1000MCM cables per phase, in underground metal duct banks to duplex step-up transformer ( 13.8kv to 138kv), two turbines per xformer, dual primary windings, single high side. These 1000 MCM cables were about 200 ft long, each.

During initial construction, contractor put all three phases in adjacent - like this
AAAA
BBBB
CCCC
XXXX
XXXX - the XXXX being open and unused.
The resulting eddy currents, melted the cable in the duct bank, they never read the print, showing the phases to be mixed and leaving open rows for cooling. Used a dozer to drag the cables out, and replaced with new, what a mess. Scrap cable guy was very happy though!

For those not familiar with cable sizes - 1000 MCM cable, is about the size of your wrist in diameter. I wish I had a digital camera back in those days. Oh yeah, EIGHT units - much work over a couple year period!
 
I have pulled much larger cable that was not electrical though. I can't remember the actual dimensions but we pulled up a huge elliptical waveguide cable for this antenna. Turns out the RF engineers were wrong and we ended up pulling up an even bigger elliptical waveguide cable.


Old school picture here. This was before OSHA was on our asses. I'm hanging waiting for my partner to hand me an antenna. This was back when climbing with lineman belts and no shock absorbing lanyard or hard hat was the norm. You can see both cables coming up the tower. I would guess they were 6" to 8" at the wide side of the elliptical.
 
Damn!!! Whole bunch of electrical guys on here that love gun shit. I love it! What was this thread about again? LOL!! I can really appreciate the towers you have climbed because I've had the exact pleasure, and know that most don't have any idea of what it's like. Only there weren't any ladders on the ones I've climbed. The poles were wood and we climb with hooks/gaffs and double belts. Only did that a little, and then back to distribution where the poles are mostly only 45 feet tall. Nothing like gloving 13,200 volts off a baker board. All you linemen know what I'm talking bout.
 
STR, I'm not an electrical guy, but a wayward mech engineer - got sentenced to work on the GT's, by a fluke, but since GT's weren't mainstream in 1980, we did all our own stuff, without help from the corporate weenies. So, if we had a problem, let's give it to Mikee, he can fix anything!!!!

One of my friends owned a high line company - I told him thanks but no, I did not wish to climb that stuff with him, for fun. Or money.

300Sniper - you can have all my tower work - I had to ride up a stack elevator as a trainee back in the late 70's, 600 ft on one, 800 on the other - did not like. Cannot imagine having to wrestle a cable like that up there! You win the baddass award today!
 
biffj said:
I built my own converter with the help of our local electrical wizards. A pile of giant capacitors, a starter capacitor or two, some switches to turn it off or on and a contactor for the switch to run, a switch that cuts out the switches when the motor starts running (keeps the manual switches from carrying power when running) and a pile of wire and boxes to put it all in. I used a 15HP 3 phase motor and it works quite well. Cost was about $300 plus my labor to assemble. I run a lathe that has a 7.5HP motor and a mill with a 3.5HP motor. Sometimes other stuff is run as well but not often. The wizards told me that every machine in line that you start up helps with power production so even with the 15HP converter I can run a lot more than 15HP total in motors. I can run both the 7.5HP lathe and the 3.5HP Mill and the 5HP chop saw and not exceed the capability. The unit should be sized to start the largest single motor you need to run....

Much better than the crackerbox starter setups. Makes real power and allows full power from your motors.

Frank
Click to expand...

When I asked above whether the American Rotary is a single phase motors and a 3 phase generator rolled in one (like the DC to 400HZ military converters) I had your set-up in mind as the alternative. It looks like the AR is what you did - just with fancier controls. (Please correct me if I am wrong).

I currently run my 3 phase stuff with a military generator that I needed anyway living almost literally at the end of the power line. This way I saved the money for the converter and the generator gets exercised regularly. (I am a hobbyist, not making my living with lathe and mill.)
 
Last edited:
alpine44 said:
When I asked above whether the American Rotary is a single phase motors and a 3 phase generator rolled in one (like the DC to 400HZ military converters) I had your set-up in mind as the alternative. It looks like the AR is what you did - just with fancier controls. (Please correct me if I am wrong).

I currently run my 3 phase stuff with a military generator that I needed anyway living almost literally at the end of the power line. This way I saved the money for the converter and the generator gets exercised regularly. (I am a hobbyist, not making my living with lathe and mill.)
Click to expand...


I'm at the end of the power line too with about 5 miles between me and any 3 phase. The original operator in this shop had 3 very large Wire EDM machines in here and needed 3 phase for them. He had 2 25HP rotary converters and 2 individual 200amp service coming in here. The power company told me there is a line conditioner on for this end of the line because the guys before me needed stable voltage. Now having said all that....I think my unit is pretty much what the AR unit is and yes they probably have fancier control circuitry. I started out in the old shop with a hand started converter that was a 3 phase 5HP motor with a pulley on it wired in to 2 of the phases and the third went to the mill motor with the 2 lines from the wall box. I wrapped a rope around the pulley and gave a mighty pull then hit the switch on the converter. If I wound it up enough it started, otherwise it lugged down and stopped. I tried to hit the off switch before that happened. This new setup works a lot better and handles the higher powered lathe motor much better. Lathes can pull a lot more than mills so it needs to be cleaner. I have had to replace a couple capacitors over the years and check voltages etc to make sure things are working right.


Frank
 
biffj said:
I built my own converter with the help of our local electrical wizards. A pile of giant capacitors, a starter capacitor or two, some switches to turn it off or on and a contactor for the switch to run, a switch that cuts out the switches when the motor starts running (keeps the manual switches from carrying power when running) and a pile of wire and boxes to put it all in. I used a 15HP 3 phase motor and it works quite well. Cost was about $300 plus my labor to assemble. I run a lathe that has a 7.5HP motor and a mill with a 3.5HP motor. Sometimes other stuff is run as well but not often. The wizards told me that every machine in line that you start up helps with power production so even with the 15HP converter I can run a lot more than 15HP total in motors. I can run both the 7.5HP lathe and the 3.5HP Mill and the 5HP chop saw and not exceed the capability. The unit should be sized to start the largest single motor you need to run....

Much better than the crackerbox starter setups. Makes real power and allows full power from your motors.

Frank
Click to expand...


You could have saved a few bucks on the starting capacitor and any other devices used to start the motor you're using for a converter. Just put a pulley on the shaft and as soon as you apply power, pull a rope that you've previously wrapped around it so the rotor now spins. Once it's up and running then throw the downstream line switches to power up the equipment. I used to see rigs like this in the remote areas I traveled to. Real inefficient and most used the "twice as big" rule of thumb. The converter motor was usually twice the HP of any motor it ran. Still need capacitors to balance voltages "downstream".

It's pretty primitive but it beats having to convert to 1-Phase with the replacement motor often twice the frame size. Also better than having someone having to ride a bicycle that runs a "belt drive" :)

In the end they work pretty good if you can keep the smoke contained in all the devices. The minute that smoke starts to leak out your done :) :)
 
alpine44 said:
Here is one of my favorite videos. The last two sentences are priceless.

https://www.youtube.com/watch?v=SkFH8lLvKZ0
Click to expand...
This video gives me a hard on! I have never gotten to actually work on a bare hands crew out of a chopper, but as part of our apprenticeship, we spent two weeks training with high line. We all got to go up in a high line bucket and bug on to a 500KVA circuit before we could graduate. Very few people get that chance, and it's an awesome experience. At our company highline work is mostly done dead and grounded any more, even though we do have a couple of crews that are bare hands qualified.

Mikee, maintaining power plants is where I started back in 1987 fresh out of the military. I wish I would have been at the combined cycle units which ran Gas Turbines, but they didn't have many of those then like they do today. I had to work at the fossil and Nuclear units instead. That's why for the last 14 years I've been a distribution lineman.
 
Deadshot2 said:
You could have saved a few bucks on the starting capacitor and any other devices used to start the motor you're using for a converter. Just put a pulley on the shaft and as soon as you apply power, pull a rope that you've previously wrapped around it so the rotor now spins. Once it's up and running then throw the downstream line switches to power up the equipment. I used to see rigs like this in the remote areas I traveled to. Real inefficient and most used the "twice as big" rule of thumb. The converter motor was usually twice the HP of any motor it ran. Still need capacitors to balance voltages "downstream".

It's pretty primitive but it beats having to convert to 1-Phase with the replacement motor often twice the frame size. Also better than having someone having to ride a bicycle that runs a "belt drive" :)

In the end they work pretty good if you can keep the smoke contained in all the devices. The minute that smoke starts to leak out your done :) :)
Click to expand...


You are indeed right about this. I ended up buying a crackerbox starter to start the motor though I really had no troubles with the ropestart method. Not being an educated electrical type I used info from someone who had more experience in these areas. It kept my machine running for a pretty good length of time. I am much happier with the current setup though. It works very well and a lot less chance of smoke leaking anywhere.

Frank
 
I may be next on the giant phase converter train. Just talked to my power company about getting 3 phase for potential cnc. I don't even live THAT far out, and they said minimum of $60k to bring it to me. I just started laughing, then cried for awhile.
 
STR said:
This video gives me a hard on! I have never gotten to actually work on a bare hands crew out of a chopper, but as part of our apprenticeship, we spent two weeks training with high line. We all got to go up in a high line bucket and bug on to a 500KVA circuit before we could graduate. Very few people get that chance, and it's an awesome experience. At our company highline work is mostly done dead and grounded any more, even though we do have a couple of crews that are bare hands qualified.

Mikee, maintaining power plants is where I started back in 1987 fresh out of the military. I wish I would have been at the combined cycle units which ran Gas Turbines, but they didn't have many of those then like they do today. I had to work at the fossil and Nuclear units instead. That's why for the last 14 years I've been a distribution lineman.
Click to expand...

Next time I fly into FLL, I'll PM you sir, beers, whiskey and seafood on Mikee - Blue Moon Seafood sound OK to you? I got sent to GT's as " please just work here for a couple years, then we will xfer you to steam turbines...." 22 years, never made to steamers, but was the GT czar for some time.

Closest I ever came to being on the electron side - we blew up a 138kv step-up transformer right outside my office window - green light thru the blinds.

Oh, and when my electrical/ops crew opened a disconnect on a operating unit - 250 MW @ 138Kv.

Oh, and when a GE contractor swung a crane into a hot 345kv bus - with 1500 MW of generation on it. Blew a crater 6' deep, 10' wide and welded a benjo ditch grate solid for fifty feet, until it found the plant ground grid. No one hurt - thought for sure, running to the sound ( set every car alarm off for a mile ) that there would be bodies everywhere. Not one scratch.

And..... William. Stuck his hand in a 7160 cable vault.....the first cable he touched, was hot. His wife, FIL and other family, all worked with us. RIP. His FIL was a good friend, we drank a lot whiskey and shot a lot of BS together, just about did him in, tough old German that he was.

Damn, I'm not the young kid anymore.....

Y'all be careful with this electricity stuff - as lethal as a loaded remington with a broke Jewelll. Get help if you need it - no second chances. OP - sorry for the hijack.
 
Last edited:
You must log in or register to reply here.

Similar threads

gr8fuldoug
New Products Intel from Camera Land
Replies
2
Views
990
gr8fuldoug
gr8fuldoug
D
Beginner - need equipment recommendations and advice
Replies
104
Views
3K
SporterII
S
gr8fuldoug
Optics GPO Binoculars, Riflescopes and Rangefinders
Replies
0
Views
290
gr8fuldoug
gr8fuldoug
U
Marburg is coming!
Replies
53
Views
2K
AK264
A
lonegunman762x51
40 years ago today.....................................
Replies
73
Views
4K
Kinetic Moose
Kinetic Moose
Top Bottom
Back