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Need a relay: 20A@460VAC or 7.5HP. any help?

Need a relay: 20A@460VAC or 7.5HP. any help?

Need a relay: 20A@460VAC or 7.5HP. any help?

(OP)
Hello everyone;

I'm working as an intern at an engineering firm this summer, and I'm building a single to 3 phase rotary converter. The idler motor I'm using is 7.5HP and rated at "22.3-20.4/10.2 Amps" and 208-230/460 VAC.

I've been searching for quite a while now and cant seem to find a main power relay which will handle this. From the instructions I have for the design, I believe I need a relay of at least the same HP rating, or twice the current rating.
Does that mean that it needs to be rated 2x10.2A=20.4A for 460VAC? if so, I cant find one. I cant find one that meets the HP requirement, either.

If anyone knows where I can get a relay that can handle these requirements, please let me know!

Thanks in advance,

Mark

RE: Need a relay: 20A@460VAC or 7.5HP. any help?

You might have better luck if you look for something called a 'contactor' or 'starter'. These operate much the same as a standard relay but are used to switch large loads.

RE: Need a relay: 20A@460VAC or 7.5HP. any help?

(OP)
Thanks, Ill do it.

RE: Need a relay: 20A@460VAC or 7.5HP. any help?

Suggestion: Visit
http://www.thomasregister.com
and type Relays under Product or Service, which will return 245 companies to approach to.
In agreement with the previous posting, the contactors are normally used for that size of motor load. The relay would be preferred if the cost, size, mounting arrangement, 1pole contact, etc. happen to be more suitable for the application

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