Need help with RPC build.....

[steamin10]

Tester: Your tone and demeanor, from what I read, is half arrogance, and half combat, for a posted question. It voilates the very open spirit of this board and those that give of their time.

Those that give advice about electrical or power devices, do so with the knowledge that not everybody is able to work safely with the conditions surrounding the tasks, and therfore may add a lot of caution to their thoughts.

Fairly speaking, to bite the hand that offers free knowlege, and parallel experience, makes you less desireable to deal with. But thats just me. Dave.

[JimGlass]

In the attachment is the circuit I use to build rotary phase converters. I is similar or exactly
what others have posted.

To start the phase converter I use a start button with 2 contacts. One contact energizes the run caps and the other contact energizes the start cap. Releasing the button disconnects the start cap. A latching relay keeps the run caps energized after the start button is released.

I just built a 10 hp phase converter and the idler starts fine by itself. I think larger phase converters need the timing relays and fancy circuits.

Tester, what size phase converter do you need?

Jim

[J. Randall]

TheTester, If you don't want to fool with relays or timers as you originally stated, I think the centrifugal switch would be right down your alley. I posted a link on page 1, but you never responded, maybe you missed it.

http://www.torq.com/phaseconverters.htm

James

[hammermill]

j randal in all my years using a centrificial switch on a rpc is a new one.

all be it a sound aproach getting the mechanicals worked out would be challenging. always fun to see something new
and kudos to all who posted ideas.

[Rosco-P]

For a 5hp RPC, nothing "complicated" or "unreliable" or even expensive about using a Steveco or similar potential relay in the start circuit. Regardless of design at least one relay (really a contactor) is needed to control the RPC and prevent a false re-start in the case of a power failure. By design, circuit breakers should not and are not intended to be used to switch the RPC (or any load) on and off (unless they are switching duty breakers). Used contactors, 2 and 3 pole, in size 1 should be easy to find. All you need to do is size the overloads properly.

[hammermill]

if one is too try this dumpster diving some sources for parts are

submersiable pump pannels/controlers, potential relays,caps,contactors

hvac equipment caps contactors(24v) control transformers disconnects and fuse holders

surplus center of nebraska is a good place to look for new parts if you dont have axcess to graingers,johnstone etc

[BadDog]

My parts were mostly donated from commercial HVAC units at the scrapper. High quality parts, and have yet to get a bad one. Got several 3 ph motors (from 1hp to 10hp) that way too, and again, have yet to get a bad one.