Question about relays for Air Shamee motors

[Mchas]

With the single phase Air Shamee motor setup with 3 motors, I currently have 3 separate relays, one for each motor. I had one go bad and caused the fuse inside my bay faceplate to burn out, but the problem was I had no way to tell which of the three relays caused it so I just replaced all three.

Now I have another bay that seems to be having a similar issue. I am wondering why I need three separate relays? Is it possible to just have a single relay that controls all 3 motors? That way I can get a better quality relay (mine are Omron cheap ones) and just replace one instead of all three.

Will that work?

 

[MEP001]

That will definitely work. What is the voltage to them? 120v? 240v? 3 phase?

 

[Mchas]

240v, three motors, single phase.

The reason I thought of this is because I know my vacuums have a single relay driving two motors, so it seems like I should be able to do the same with the three air shamee motors. But then why do the install instructions have three separate relays?

 

[MEP001]

Most likely because it was cheaper. I can get those Omron relays for $6 each. A good DP relay is more like $40. When you run 240v, you're supposed to break both legs, so technically they're doing it wrong. You need a heavy contactor because the inrush current is 60-80 amps.

 

[Mchas]

Would one like this work? I use these for my vacuums and have several on hand.

Square D 24VAC Non-Reversing Definite Purpose Contactor 3P 30A, Width: 2.5 in 8910DPA33V14 | Zoro

Order Square D 24VAC Non-Reversing Definite Purpose Contactor 3P 30A, Width: 2.5 in, 8910DPA33V14 at Zoro.com. Great prices & free shipping on orders over $50 when you sign in or sign up for an account.

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This is a 3 pole but I could just use two? One for each leg of the 240v.

I could have the two wires come into this contactor and then have the two wires come out and split into three each, to connect to the motors.

Would that work?

 

[MEP001]

I'd go with this one:

Square D 24VAC Non-Reversing Definite Purpose Contactor 1P 40A 8910DP41V14 | Zoro

Order Square D 24VAC Non-Reversing Definite Purpose Contactor 1P 40A, 8910DP41V14 at Zoro.com. Great prices & free shipping on orders over $50 when you sign in or sign up for an account.

www.zoro.com