Troubleshooting 1/8 HP Motor w/ SCR & Relays

Thread starter jloom977
Start date Jul 13, 2015
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Motor Scr Troubleshooting

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The discussion centers on issues with welded relay contacts in a 1/8 HP motor setup using an SCR type DC drive and 1/4 HP AC single-phase control relays. The user questions whether switching to 1 HP relays is necessary, given that the motor's horsepower is lower than that of the relays. It is noted that motors typically draw significantly more current during start-up, which may contribute to the relay problems. The conversation highlights the importance of considering the inrush current when selecting relays for motor applications. Addressing the relay specifications may be crucial to prevent future contact welding issues.

Jul 13, 2015

jloom977

I am using an 1/8 HP motor with an SCR type dc drive and 1/4hp AC single phase control relays. I keep having a problem with welded relay contacts. Should I go to 1H/P relays? I don't know why I would have to being the HP of the motor is lower that the relay?

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Jul 13, 2015

Dr. Courtney

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Motors draw a lot more current on start-up.

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