So many posts about phase conversion to 3-phase

The new lathe arrived today. UPS called and said it would be delivered yesterday, but they were wrong. It missed the truck in Kansas City. Nonetheless, it's here today.
so is a 10hp rotary phase converter. It was listed on Craigslist about 70 miles from my home. I offered a low-ball offer and he came back with a slightly low-ball price. I committed and traveled to Burleson, Texas to pick it up. Tested it on 220 VAC and it started and ran quietly.

I had also made a low-ball offer on eBay for another rotary phase converter; not expecting to win it. This one included a manufactured control box and a 10hp motor with a shaft sticking out. To my surprise, the seller agreed to my low ball offer. So I paid for it. Now, I have two nice 10hp rotary phase converters. Not sure which I want to use for my workshop. Will sell the other.

When UPS delivered, the worker said that they're not allowed to drive in allys. Bummer. I'd even gone to the local UPS freight office a couple of days ago to make sure that they could deliver via bobtail and liftgate in my rear entry. They said yes. Today, they said, "No".
Without a plan B, I didn't know what to do! Too far to walk it around back on a pallet jack. But the UPS guy was very friendly and cooperative. He understood my plight. so he drove to the end of the alley where we off loaded. Then, I used a towing strap and my pickup to pull it about 300 yards up the alley to my driveway. I tipped him very nicely! He deserved it.

Took all the rest of the day and into the night to get it uncased and moved into my workshop. I have a 4,000 lb shop hoist. It did the job nicely, although lifting it off the foot-tall pallet was a chore requiring lifting the pallet 8" in several steps with cribbage so that the legs of the shop crane would go under. With my towing strap, I was able to raise the lathe off the pallet, slide the heavy pallet out, and lowered the lathe to the pavement (after removing the center panel and brake so that the legs would fit without bending the brake). Pulled it into my workshop with a come-along and put it in its new home. It'll be there now for the duration. It's going to take days and plenty of solvent to get the preservative off. Then, I'll hook up the phase converter (still not sure which converter to keep and which to resell), and go through the several pages of initial lathe setup. I think I'll take a break and level it tonight.

I think I should start a new post about setting up my new 14 x 40 lathe in case anyone is interested.

LatheUPS.JPG


Lathe2.JPG


LatheinShop.JPG
 
The new lathe arrived today. UPS called and said it would be delivered yesterday, but they were wrong. It missed the truck in Kansas City. Nonetheless, it's here today.
so is a 10hp rotary phase converter. It was listed on Craigslist about 70 miles from my home. I offered a low-ball offer and he came back with a slightly low-ball price. I committed and traveled to Burleson, Texas to pick it up. Tested it on 220 VAC and it started and ran quietly.

I had also made a low-ball offer on eBay for another rotary phase converter; not expecting to win it. This one included a manufactured control box and a 10hp motor with a shaft sticking out. To my surprise, the seller agreed to my low ball offer. So I paid for it. Now, I have two nice 10hp rotary phase converters. Not sure which I want to use for my workshop. Will sell the other.

When UPS delivered, the worker said that they're not allowed to drive in allys. Bummer. I'd even gone to the local UPS freight office a couple of days ago to make sure that they could deliver via bobtail and liftgate in my rear entry. They said yes. Today, they said, "No".
Without a plan B, I didn't know what to do! Too far to walk it around back on a pallet jack. But the UPS guy was very friendly and cooperative. He understood my plight. so he drove to the end of the alley where we off loaded. Then, I used a towing strap and my pickup to pull it about 300 yards up the alley to my driveway. I tipped him very nicely! He deserved it.

Took all the rest of the day and into the night to get it uncased and moved into my workshop. I have a 4,000 lb shop hoist. It did the job nicely, although lifting it off the foot-tall pallet was a chore requiring lifting the pallet 8" in several steps with cribbage so that the legs of the shop crane would go under. With my towing strap, I was able to raise the lathe off the pallet, slide the heavy pallet out, and lowered the lathe to the pavement (after removing the center panel and brake so that the legs would fit without bending the brake). Pulled it into my workshop with a come-along and put it in its new home. It'll be there now for the duration. It's going to take days and plenty of solvent to get the preservative off. Then, I'll hook up the phase converter (still not sure which converter to keep and which to resell), and go through the several pages of initial lathe setup. I think I'll take a break and level it tonight.

I think I should start a new post about setting up my new 14 x 40 lathe in case anyone is interested.

LatheUPS.JPG


Lathe2.JPG


LatheinShop.JPG
 
Nice looking machine, will be waiting for install and setup pics and story.
 
Phase converter all wired up with appropriate fused (breaker) power main and supplying 3-phase power to my lathe. All seems well.
HOWEVER, the idling current draw of the converter seems excessive. With no 3-phase load, the converter/motor is drawing 15 amps on one leg and 14 on the other from the single phase power main. I was expecting much lower power consumption when not under any load other than its own internal friction and power losses. (like almost zero . . .just enough to keep the Phase Converter spinning.

Does 14 amps and 14 amps sound correct?
 
14A @ 10hp is quite good for an idling 3 phase motor on single phase supply
is your line voltage closer to 220v or is it closer to 240v?
 
Phase converter all wired up with appropriate fused (breaker) power main and supplying 3-phase power to my lathe. All seems well.
HOWEVER, the idling current draw of the converter seems excessive. With no 3-phase load, the converter/motor is drawing 15 amps on one leg and 14 on the other from the single phase power main. I was expecting much lower power consumption when not under any load other than its own internal friction and power losses. (like almost zero . . .just enough to keep the Phase Converter spinning.

Does 14 amps and 14 amps sound correct?

It does seam rather high, I assume we're talking about a rotary converter here. does it spin freely with the power off, , (bearings), what size is the motor? could you be measuring circulating currents by measuring the phases? what is the current draw back at the single phase supply?
 
It does seam rather high, I assume we're talking about a rotary converter here. does it spin freely with the power off, , (bearings), what size is the motor? could you be measuring circulating currents by measuring the phases? what is the current draw back at the single phase supply?

I'll need to go measure the unloaded 220VAC primary to see if it's closer to 240V or not.

Bobshobby, the current draw is measured at the single phase supply to the 3-phase motor while it is running and there is absolutely no 3-phase load at all. It seemed high to me and would add a hunk of $$$ to our electric bill if the phase converter was accidentally left ON overnight.

I was going to mount the converter outside in a weather-resistant enclosure to get the noise out of the workshop. But that invites accidentally leaving it energized. I should put a motor timer on the motor start that turns it off in 3 hours unless I extend the time.
 
Phase converter all wired up with appropriate fused (breaker) power main and supplying 3-phase power to my lathe. All seems well.
HOWEVER, the idling current draw of the converter seems excessive. With no 3-phase load, the converter/motor is drawing 15 amps on one leg and 14 on the other from the single phase power main.

That might not be energy that you're paying the power company for; there's a phase-angle correction,
which you can check. Turn off electric water heater and furnace/AC, look at five minutes of
power-company-meter reading with the RPC running, then turn it off and look at another five minutes.

Some of the current you're measuring is due to the start/run capacitors in the RPC, and doesn't
mean real electric power. The power meter indicates this, but ammeter measurements don't.
 
I'll need to go measure the unloaded 220VAC primary to see if it's closer to 240V or not.

Bobshobby, the current draw is measured at the single phase supply to the 3-phase motor while it is running and there is absolutely no 3-phase load at all. It seemed high to me and would add a hunk of $$$ to our electric bill if the phase converter was accidentally left ON overnight.

I was going to mount the converter outside in a weather-resistant enclosure to get the noise out of the workshop. But that invites accidentally leaving it energized. I should put a motor timer on the motor start that turns it off in 3 hours unless I extend the time.

OK you had me a little confused, you said 15A on one leg and 14A on another, I assumed you were referring to phase leads, so am I to assume you are referring to the single phase active and neutral leads,if so they should read the same. I still think it's rather high although Ulma doctor says it's about right. And I suspect he knows more about it than I do. It will be interesting to see how much it draws when running a good 3 phase load.

As for running the RPC outside or in any out of the way place, you could wire up a lamp that will show when the RPC is powered on. A mate of mine did that with his shop compressor, he had a green light next to the remote on off switch.
 
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