I am working on building a 7.5 hp rotary converter. I plan on using a start circuit with start cap that drops out after a potential relay senses enough voltage in the generated leg. Grainger has a listing of potential relays but I really don't like dealing with them as I am not a business and their past stock levels leave much to be desired. I preferr McMaster Carr for service and ease of ordering. Strangely enough, McMaster has zero listings for "potential relay" but has plenty of double throw relays.
It appears to me, a double throw relay, one that can be wired either normally off or normall on, should be able to work just fine as long as the voltages for the relay cutout are appropriate. Is a potential relay simply a "normally on" relay with a certain or adjustable cutoff voltage?
I've got most all the hardware to start putting together this converter except for the start cap and relay. I know what I need for a start cap. Any help on specs for a relay that will do the job is greatly appreciated.
Here is a shot of my 3 hp converter I built over three years ago. I outgrew it and thus a 7.5 hp unit. Will be up for sale as soon as I get my 7.5 hp unit together.