New shop equipment 3ph help

Criminy sakes, who cares what you call it when it costs $7000 for a 20 hp unit. My 20 hp RPC was purchased turn-key from American Rotary (Fat Man) to go along with my 5 hp (Little Boy) for only $1500 six months ago.

Rotary gives you a sine wave with lots of inrush capacity. Both can power multiple machines on a single install. What makes digital so great at five times the price?
 
pontiac428 said:
Criminy sakes, who cares what you call it when it costs $7000 for a 20 hp unit. My 20 hp RPC was purchased turn-key from American Rotary (Fat Man) to go along with my 5 hp (Little Boy) for only $1500 six months ago.

Rotary gives you a sine wave with lots of inrush capacity. Both can power multiple machines on a single install. What makes digital so great at five times the price?
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I know three people who's machines with digital controls were fried by an American Rotary 3rd leg over-voltage output. If your equipment has digital electronics, a Phase Perfect will provide consistent balanced power for the whole shop. I've also see Kay Industries rotary phase converters have such a wild manufactured leg that they fried contactor relays.
 
RPC wild legs float only when there is no load. They pull to within a few percent once a load is applied. The only digital equipment on my RPC is a DRO, which is buffered by its own power supply and fed from the true legs. Contactors don't like wild legs because the no-load float falls out of delta-V. So don't hook up contactors to the wild leg. I don't see the benefit of spending $7000 over a $1500 RPC. I also think there is more to it than plugging it in, you have to know where your phases go in the machine to avoid wild leg issues. Not a show-stopper compared to how shallow my pockets feel in this particular conversation.
 
davidpbest said:
I know three people who's machines with digital controls were fried by an American Rotary 3rd leg over-voltage output. If your equipment has digital electronics, a Phase Perfect will provide consistent balanced power for the whole shop. I've also see Kay Industries rotary phase converters have such a wild manufactured leg that they fried contactor relays.
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All rotary phase converters are not created equal, if the ones without digital voltage controls for agricultural use, simple motor use like irrigation pumps are certainly not suited to use with modern loads with electronics involved.
before I wired in may Haas lathe I checked generated leg unloaded, while running a small load like a BP mill, and with my big 10hp Monarch starting and running loaded. Only ever a few volts difference. My old home made one with a cap bank tuned pretty well still allowed the generated leg to vary all over the place depending on load. So off it went and in came a proper modern generator.

Even phase perfect advises strongly against using the generated leg for the single phase portions of the mixed loads. When you wire in complex loads make sure that the controls are on the line phases. Properly chosen and wired rotary phase converters are a valid choice, nothing against phase perfect but the price. Voltage doubling is a cool feature of you can use it, nice and quiet, and if the price doesn’t scare you then go for it. if going rotary make sure you get a controlled version and wire it properly.
 
pontiac428 said:
RPC wild legs float only when there is no load. They pull to within a few percent once a load is applied. The only digital equipment on my RPC is a DRO, which is buffered by its own power supply and fed from the true legs. Contactors don't like wild legs because the no-load float falls out of delta-V. So don't hook up contactors to the wild leg. I don't see the benefit of spending $7000 over a $1500 RPC. I also think there is more to it than plugging it in, you have to know where your phases go in the machine to avoid wild leg issues. Not a show-stopper compared to how shallow my pockets feel in this particular conversation.
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I'm not trying to talk you out of your rotary, or the OP into the Phase Perfect. I'm just trying to present all the facts to the OP so he can make an informed decision. I'm glad you like your RPC. I liked mine too until it blew up the controls on my $70K panel saw. Over a 10 year period, I've saved the difference in cost between the Phase Perfect and a rotary by eliminating the "idle time" power consumption. To each their own.
 
I have no issue with the technology, just the price difference makes no sense. Face it, it's an exorbitant cost to buy solid state.

David, no offense intended good sir, devil's advocate here, but I have a hard time telling the rhetorical difference between a statement like, "until it blew up the controls on my..." ...and a statement like "my skills weren't up to snuff" or "I didn't check the schematics." See how easily one could be put off or confused when discussing systems with a degree of complexity and variables like this?
 
Lets put the price in the proper perspective with regard to the application requested, we are talking about either a 5 Hp or 7.5Hp combined motor load. At the end of the day if one is spending $30-40K on the machines, then the Phase Perfect seems to be a comparable option to an RPC, quieter and much more efficient. Neither the lathe nor the mill have complex controls, so the wiring of the phases would not be an issue.
Phase Perfect 5HP 230V Digital Phase Converter - Phase Perfect® Simple is $1332
Phase Perfect 7.5HP 230V Digital Phase Converter - Phase Perfect® Simple is $1805
Phase Perfect 7.5HP 230V Digital Phase Converter - Phase Perfect® Enterprise is $2300

American Rotary Phase converter figure for 5 Hp motor or 7.5 Hp motor (multiple machines) and shipping costs will be higher.
ADX-10 is $1399
ADX-15 is $2169
 
pontiac428 said:
I have no issue with the technology, just the price difference makes no sense. Face it, it's an exorbitant cost to buy solid state.

David, no offense intended good sir, devil's advocate here, but I have a hard time telling the rhetorical difference between a statement like, "until it blew up the controls on my..." ...and a statement like "my skills weren't up to snuff" or "I didn't check the schematics." See how easily one could be put off or confused when discussing systems with a degree of complexity and variables like this?
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Great, then don't buy a Phase Perfect. It's not for everyone. For me, it was one of the best upgrades I've made to my shop. As @GT-6 Racer says, there are indeed differences between various brands and models of rotary converters. If you want the specifics behind my experiences with "voltage stabilized" rotary converters, then DM me - I doubt t it would be helpful to the OP.
 
This is a Ford/Chevy thing for the most part. I ran a Teco VFD on my Bridgeport when I first got it. I planned to wire external controls and make an enclosure for it, but two things kept me from that route. One, I can't stand the fan noise it makes (imagine a huge computer in your face) and I bought several more 3-phase machines.

I decided to go with an RPC and looked hard at both American Rotary and North America Phase Converter Co and went with the North America ProLine-7.

American Rotary has an AR-7.5 (7.5hp) unit that sells for $1,479. North American has their PL 7 (7.5hp) unit that sells for $944. I couldn't see any real reason for the $500 price of the NA and I'm extremely happy with the PL-7. I can hear it running, but it is nowhere near as annoying as the VFD...if nothing else, the RPC is at minimum 15ft from the closest machine, and it's a lower frequency sound so I forget it's even running.
 
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