Phase converters help needed..

[Mike Kees]

I have decided that I am going to buy and install a phase converter in my shop. I need help figuring out a solid brand to buy. So far I have found American rotary and North American phase converters online. Does anyone have experience with these companies or suggestions of others I should look at ? Thanks for any help,Mike.

[Andrew Hughes]

Phase master is my current Rpc.
Before that I had one made by Phoenix phase converters.
My current one is so quite I can barely hear it running and it’s not because I’m getting old.

[Mike Kees]

Andrew is that Phasemaster, by Kay Industries ?I found their website about an hour ago. What size is your converter and what do you power with it ?

[David Kumm]

When comparing, keep in mind that some companies ( Kay and Arco ) rate their units by the largest hard starting motor it will start, and others by either an easy start application or total load. Quality of motor is important as is the range of motor sizes you will be using. A RPC is adjusted for one motor size but will handle a range. The only one that is balanced for any load is the Phase Perfect which is about double is cost. They are sweet though. Dave

[jack forsberg]

depending on how many machines and how large the motors VFDs are the best. i can offer you about 20 hp for less than $1000 and that is 2 5hp vfd machine 2 3 hp vfd machies and 2 2 hp vfd machine . that is 6 machines with true 3 phase full power, cleanest power there is and no ilider .

[Mike Kees]

Jack I sent you a PM.

[Bradley Gray]

I have a 10 hp Kay Phasemaster. It starts my old Monarch 10hp planer without strain and will run the planer, 4hp blower and 5hp jointer.

Before the Kay I ran the planer with a homemade 7hp RPC. The increase in power was amazing.

[Mike Kees]

thanks for the reply Bradley. This is good information. It appears to me that there is no consistent standard on how to rate converters on their individual performance. Dave how do you compare actual performance capability of different brands ? If a Kay says 10h.p. it means it will start and run 10h.p. However another company says I need a 20h.p. unit to start a 10h.p. load. Are the idler motors different ?One is what it can start and the other guys are giving you what it can run in total load ? Seems like it is the same but some companies are doing it one way and the others get there backwards. Feel free to educate me if this is wrong.Confused,Mike

[Bradley Gray]

The metal plate on my Kay clearly states it will start 10hp and run 30hp.

[jack forsberg]

Jack I sent you a PM.

PM sent

RPC can only be tuned to one motor

here i am balancing my shop built RPC


to size a RPC you need an ilder 2 time the size of your largest hard start motor to perform well .

[Charles Lent]

The best way to choose the size of a rotary phase converter is to provide the company selling you the phase converter with a list of the motors that you will be connecting to it and note any slow starting information for each motor and let them pick the size that you need. In picking a rotary converter size on your own it's best to choose one that is at least about 20% larger than the largest hp motor that you will be connecting to it. You also need to take into account the total horsepower of all of the motors that will likely be running at any given time.

Charley

[jack forsberg]

the real cost of a RPC is the infrastructure of wiring them in to the shop


here is mine

[David Kumm]

My 10 hp Kay would start any ten hp motor I have and a 12 hp sander. My 10 hp Phase Perfect actually starts those motors easier and faster than the Kay. If you research, I believe Kay and maybe some others run a heavy specially built motor to eliminate the start caps- or something like that. Talk to all the companies but Kay, Arco, Am Rotary and a few others are pretty large. Dave

[Van Huskey]

The road to determining what source of 3ph power to use can be simple or difficult, mainly depending on budget and which and what number of 3ph machines you want to run. For some they know exactly what machines they will have in 10 years, for the others that live to search auction sites and the machinery exchange on Woodweb it can be far more difficult.

VFDs are inexpensive and actually CONTROL the motor which allows for adding many "features" like soft start, braking, speed control etc. They do essentially fall out of the running if you plan to run a bunch of 3ph machines or want to go over 5hp.

RPCs are the economical options (I am not considering static phase converters) especially if you plan to run a shop full of 3ph machines and or go over 5hp. One nice thing is when the shop is wired with 3ph circuits the 3ph machines are plug and play you can use the machines starters etc vs wiring around them with a VFD. As noted different companies rate differently each has their own reasons, all of them are logical in their own way and you simply have to decide what is the load type and HP of your machines for the starting side of the equation along with the highest total HP you will run simultaneously then use the companies sizing charts to determine the smallest RPC from that company that works for you. You may want to size up but not too much as the larger an RPC is the more electricity it takes to run and the less optimized it is for the actual loads you are running. While some companies build better RPCs than others for woodworking machines most people find American Rotary fine.

Phase Perfect is warranted if you have machines with lots of electronics. Most RPC companies make models with cleaner and better balanced power for these types of machines but I would use a Phase Perfect on big Euro machines with lots of electronics like shapers and some sliders, those parts are EXPENSIVE to replace.

I ended up going the RPC route simply because I am over the 5hp with a couple of machines. If it weren't for that I would have stuck with VFDs even if the price favored an RPC just for the extra control.