Phase converter specifically phase perfect question..

[Patrick Walsh]

Ok I’ll try and keep this one simple.

I have two new/old machines both three phase. One 7hp the other 7.5-9hp. Yeah don’t ask I can’t figure out how it’s two horsepower’s?

I’m buying a 10 hp phase perfect. The manufacturer saiz it needs 60-70 amps to run the unit.

I have a 100 amp service now totally maxed out regarding breakers. I’ve already done the sub panel.

So in that maxed out 100 amp service I have two separate 30 amp breakers. One runs my tablesaw one runs my shaper. Well the shaper is gone and sold, the tablesaw I still have. I intend that when I get my new sliding saw up and running the tablesaw will also go.

So the question. If I no longer have the need for the two 30amp single phase breakers as I’m replacing the two machines they powered with three phase machines do I really need a panel upgrade or will I have the 60-70 amps available needed to power my phase perfect and thus my tow three phase machines.

Being I only run one machine at a time in my shop baring a dust collector. My dust collector is single phase shouldn’t I be fine with my 100 amp service.

Hope that all makes sense?

[Darcy Warner]

I ran a 15hp (not PP, because that's too much money) off a 60amp circuit. my hard start was a 7.5hp DD planer, only when cold did I have issues.

[Patrick Walsh]

I’m buying it used.

So I am thinking right then.

The 10 hp phase converter needs 60-70 amps to generate 10 horses of three phase power.

So it goes something like main panel. Seventy amps of breakers dedicated and run out to say a knife shutoff in front of the phase perfect. Then the phase perfect with a sub pan;e out of it with whatever lines I need out of it to my machines. So in my case the sub panel after the phase perfect would have whatever size breakers needed in it to power my machine. So long as I run one machine at a time I’m all good. I could even put knife shutoffs at the machines as if they were hardwired.

Am I making sense or is this getting scary.

I’m gonna have a electrician instal the phase perfect but if I don’t need the panel upgrade I’m gonna be In a way better situation than I thought.

I do seem to think I have seen a number of people instal there own phase converters however.

Can’t be to hard if your just coming out to the panel to a knife shutoff then to phase converter then out of the phase converter to the machines.


I ran a 15hp (not PP, because that's too much money) off a 60amp circuit. my hard start was a 7.5hp DD planer, only when cold did I have issues.

[John Gustafson]

You are pushing it, but I think you know that you know that or you wouldn't be asking. Sure, you can run a 60 amp breaker in place of the two 30's. Might even give you an open slot in the panel.

[Tom Bain]

Patrick — I have the 10HP Phase Perfect Unit which I recently installed in my new shop and it is set-up almost exactly as you described. I have a 70 amp double pole breaker in the main panel which connects to a cutoff switch via 6AWG THHN wire. Then the output of the cutoff switch feeds the input to the phase perfect unit. The output of the phase perfect feeds a 3-phase sub-panel, and then individual breakers in the 3-phase panel are dedicated to each 3-phase machine (table saw, drum saner, planer, etc ...). Only one machine running at a time, and my largest motor is currently 7.5HP.

I installed everything myself, and if you are familiar with electrical wiring it’s not terribly difficult. Hardest part was mounting the phase perfect to the wall by myself as it’s a tad heavy and a little cumbersome.

[Darcy Warner]

Just a 100amp service to the house? Or down off main panel in house?

The first, yes, but you are really close to the edge.

Second no worries.

[Patrick Walsh]

Hmm,

Really stinks I’m 10 amps short.

I’m sure it will be fine on 60 amps but darn what a bummer.

Good to hear the instal is so easy as I could really really use the savings.

To think I may be up and running with three phase by months end is very exciting. I have been waiting for new,ray two years to make a cut with the Martin.


Patrick — I have the 10HP Phase Perfect Unit which I recently installed in my new shop and it is set-up almost exactly as you described. I have a 70 amp double pole breaker in the main panel which connects to a cutoff switch via 6AWG THHN wire. Then the output of the cutoff switch feeds the input to the phase perfect unit. The output of the phase perfect feeds a 3-phase sub-panel, and then individual breakers in the 3-phase panel are dedicated to each 3-phase machine (table saw, drum saner, planer, etc ...). Only one machine running at a time, and my largest motor is currently 7.5HP.

I installed everything myself, and if you are familiar with electrical wiring it’s not terribly difficult. Hardest part was mounting the phase perfect to the wall by myself as it’s a tad heavy and a little cumbersome.

[Patrick Walsh]

My house has a 100 amp service.

Electric stove central air.

Small hose though and I have never ever been able to trip the circuit on anything even mid summer when working in my sho. I can run the 5hp dust collector, then two 4hp machines at the same time and I have been totally fine.

But this is probably a tad different being I’ll be asking for my main panel to draw 60 amps to the phase converter. Or is the phase converter actually only using 60 amps is the,canines it’s connected to it are in need of the full 60 amps.

But regardless I’m 10 amps short with nothing I can just get rid of. I could replace my electric stove with a gas stove as I have natural gas and that would free up a 50amp breaker. But that’s a slippery slope as the plumber will cost like a electrician then the stove I want is stupid expensive then I need a new kitchen and dragging a new stove into a kitchen that won’t get renovated for another 3-5 years makes zero sense.


Just a 100amp service to the house? Or down off main panel in house?

The first, yes, but you are really close to the edge.

Second no worries.

[Tom M King]

Water heater? Dryer? might have to be careful what's running at the same time. It won't matter if you turn enough stuff off.

[David Kumm]

The additional input amperage allows for a cushion when starting machines that spike the amperage but I doubt your saw will need it. I can run a PP off a 50 amp breaker for my 9 hp SCMI slider with scoring. DC is on a separate circuit. The 70 amp input assures that a 10 hp hard starting machine can be run but you can get by with less. The PP will use less amps than an rpc of similar size so you will be fine with your minimum amps unless the rest of the house is using too many at the same time. Dave

[Darcy Warner]

My 15hp drew like 7amps just idling.

Its rated for inrush, which can be high.

60amp feed will be fine.

[Patrick Walsh]

And how do people feel about setting up these converters without a electrician.

I think by now people round here get a idea of what I can and can’t do.

On a side note I can’t help after last night show wanting to go about and get myself a hot pink suit cowboy boots and cowboy hat.

I know left field.

[Darcy Warner]

And how do people feel about setting up these converters without a electrician.

I think by now people round here get a idea of what I can and can’t do.

On a side note I can’t help after last night show wanting to go about and get myself a hot pink suit cowboy boots and cowboy hat.

I know left field.

Not very difficult really.

[Patrick Walsh]

I figured.

Thanks for all the help everyone.

You should all expect a letter from my layer in no time lol..




Not very difficult really.

[Steve H Graham]

I have 100 amps to my shop, and my biggest draw is a 7.5-HP lathe. I have #3 wire to the Phase Perfect's subpanel. I'm pretty sure I have the Phase Perfect on a 60-amp breaker. If it draws too much power, hey, that's what the breaker is for. Until it pops, I consider the circuit more than adequate.

I didn't "install" my Phase Perfect. I created an outlet and plugged it in.

[Rod Sheridan]

Patrick, the phase converter, aside from no load current will only draw enough power to supply the load.

Since this is a house I presume the machines are for hobby use?

With central air, a stove, a water heater, and house base load, you're really close to capacity without the shop load.

I would curtail the dryer or stove and not worry about it further. It's extremely unlikely that your continuous shop load will be more than 6 HP including dust collection......Rod.

[Jeff Bartley]

I'm pretty sure the Phase Perfect will draw only the amps that the machine it's running will draw. In other words, as long as you're not absolutely maxing out the 10hp you should be just fine on a 60 amp breaker.
As to setting it up yourself, there's nothing terribly difficult but when I built my shop I had to have an liscenced electrician set the panels so I also had them run wires to the Phase Perfect and it's panel.
Just remember to change the line capacitors if you're buying used......and then every 3 years after that.

[Chuck Saunders]

The breakers in your panel do not add up to the main breaker value. You removed your shaper so your PP breaker 70 amp goes there. If the assortment of loads exceeds your main breaker 100 amps then it will trip otherwise your good to go. If you find your main breaker tripping then the message is your electrical service is insufficient for your needs.
Chuck

[Patrick Walsh]

Thanks everybody.

I think you all confirmed what I was thinking.

With the two machines going “shaper and ts” each on a dedicated 30 amp breaker I now have the 60 amps needed to power the phase perfect.

My plan is going to be as follows.

Replace two double pull 30 amp breakers with a 60 amp double pull. Sixty amp breaker to knife shutoff. Out of knife shutoff to phase perfect. All this is with 6 gauge three wire so far if I’m understanding correct. Then out of the phase converter with four wire of the appropriate gauge to a sub panel dedicated to my three phase machines. Inside the sub panel I will have breakers sized appropriate for my machines. 7.5 hp and another 7.5-9hp however that works. Out from each breaker goes the appropriate gauge four wire to the appropriate plug end for whatever three phase plug and cord I have coming out of my machines.

Should be easy peasy.

And it should save me a bundle. I’m sure the electrical supplies alone will cost more than a few bucks themself but whatever non of this is at all inexpensive ever.

[Tom M King]

If you use metal conduit, or whatever kind of metal connector to the boxes, put a plastic bushing over the end of the conduit/connecter in the boxes. If people off the street can buy from electrical suppliers there (some states don't allow it), the prices will be much lower than the box stores.

Run any conduit first, and then measure for the wire, since you will probably be buying cut lengths. Buy enough to have a little bit to throw away. If you buy the wire first, you are guaranteed to come up a foot short.

https://images.homedepot-static.com/productImages/bd9ad6e6-5baf-4f08-aa98-a7d00f51d780/svn/halex-conduit-fittings-27529-64_1000.jpg

[Bill Dufour]

Watch c-list and ebay to buy used panels and wire/cable.
Bill D

[Patrick Walsh]

I’ll run EMT everywhere.

When I added a sub panel and dedicated circuit breakers and outlets I had a licensed electrician my then boss used at the time do the work. He ran EMT everywhere and put all the outlets in metal boxes.

I’ll do the same as it’s very very nice.

So what’s the suggestion with the plastic ends for other than cables not cutting? The metal boxes have those round plastic lined clamps whatever they are called.


If you use metal conduit, or whatever kind of metal connector to the boxes, put a plastic bushing over the end of the conduit/connecter in the boxes. If people off the street can buy from electrical suppliers there (some states don't allow it), the prices will be much lower than the box stores.

Run any conduit first, and then measure for the wire, since you will probably be buying cut lengths. Buy enough to have a little bit to throw away. If you buy the wire first, you are guaranteed to come up a foot short.

https://images.homedepot-static.com/productImages/bd9ad6e6-5baf-4f08-aa98-a7d00f51d780/svn/halex-conduit-fittings-27529-64_1000.jpg

[Tom Bain]

I thought about running EMT and pulling THHN for the 3-phase circuits to the machines, but quickly learned that bending conduit is a skill that I wasn’t going to master quickly. So, I just used 10-3 NM wire (Romex) instead and it worked great and was a lot easier.

[Tom M King]

Doesn't matter what they're for other than being required by code. You don't get to argue that they aren't needed. It's a detail left out by many DIYer's the first time, and not one you want to re-do. Insulation is why those push through connectors are there too, just to save a step since they are required anyway.

[Steve Fish]

I’m not looking to derail here but I have a question that might be relevant. Is it possible to have some sort of transfer switch at the main panel that would shed other house circuits while the PP is in use? I might be going down the same path in the future so following this one. Thanks

[Brian Holcombe]

Tom, are you talking about the anti-short bushings?

[Rod Sheridan]

Tom, are you talking about the anti-short bushings?

I think he's referring to insulated throat connectors. Instead of installing an insulating bushing on the end of the connector, you can buy connectors with a built in plastic sleeve, same sort of thing as an anti-short bushing for BX........The nice thing about insulated throat connectors is that you don't have the space wasted by the insulating bushing.

Regards, Rod.

[Alan Lightstone]

I was told that I needed 80 amp breakers for my 10HP Phase Perfect. That's what Phase Perfect's website says, and what I had put in.

I run that off my 200 amp subpanel. FWIW.

I Don't have any machines that exceed 10HP. My Grizzly 10HP widebelt sander runs just fine off it. No issues at all.

[Tim Otto]

I have 100 amps to my shop, and my biggest draw is a 7.5-HP lathe. I have #3 wire to the Phase Perfect's subpanel. I'm pretty sure I have the Phase Perfect on a 60-amp breaker. If it draws too much power, hey, that's what the breaker is for. Until it pops, I consider the circuit more than adequate.

I didn't "install" my Phase Perfect. I created an outlet and plugged it in.

The breaker is there to protect the circuit, not the load.

[Jim Andrew]

We removed an electric range and put in a new gas one, not a big deal. Of course, my son is a plumber.

[Patrick Walsh]

Yeah that’s a solution but expense as a wolf duel rule indiction top is what I want. Actually probably not a solution with the indication top so scratch that.

I hate the idea of messing with gas. And Im talking even by a licensed plumber. Freaks me out having the crap in my house.


We removed an electric range and put in a new gas one, not a big deal. Of course, my son is a plumber.

[Don Sundberg]

You could probably run the 10 hp phase converter with a 30 amp breaker but not with the loads you are looking at running. I ran my 10 hp phase converter off of a 30 amp circuit until this weekend. It wouldn't start my new metal lathe but did fine with the 2hp jointer, 2 hp drill press, 1 hp belt grinder and 3 hp mill for years. The lathe had too much start up load as it starts the motor and gearbox at startup instead of having a clutch setup. Changed out to a 60 amp and all is good.

Don