1. Dual Speed Wiring Question

I just received my Dual Speed A.O. Smith motor to replace my toasted one speed Hayward. I have a question on wiring the dual speed switch.

I have three connections. L1, L2, and A. I currently have both my 120v phases wired into L1 and L2. And I have my A disconnected from the neutral. According to the diagram, L1=HI, L2=COM, and A=LO. So when I switch to LO, the switch will remove one of my 120 phases from L1, and A will go to neutral, running it at 120V.

Am I correct on this?

Reason I ask, I don't have the dual switch yet, but it's coming. And I'm just wanting to make sure I'm understanding the function of the motor.

2. Re: Dual Speed Wiring Question

Not exactly. The way they work is there are two sets of windings and you're either running on one set of windings or the other. The voltage doesn't change.

I'd feel better about the following advice if I knew the motor data (model, hp, voltage, etc) but here's how it works.

The L2 (com) is neutral on a 115v motor and L2 (2nd hot) on a 230v motor.

115v motor wiring;
You need a SPDT (Double Pole Double Throw) Center Off switch.
The Hot feed goes the the center pole on the switch.
The high speed terminal (L1) goes to one of the side poles of the switch.
The low speed terminal (A) goes to the other side of the switch.
Neutral goes to L2 (Com).

230v motor wiring;
You need a DPDT (Double Pole Double Throw) Center Off switch.
One of the Hot leads goes the the center pole on one side of the switch.
The high speed terminal (L1) goes to one of the side poles on the same side of the switch as the first hot lead.
The low speed terminal (A) goes to the other side pole one the same side of the switch as the first hot lead.
The second hot lead goes to the other side of the switch.
The L2 (Com) terminal wires to one of the switch termminals on the same side of the switch as the second hot.
A jumper needs to be ran between the side poles of the switch terminals that the second hot is going to.

Maybe this drawing will make it a little clearer. Not exactly how I described but close enough. I'd wire it without the first switch (DPST) and break both lines through the DPDT Center Off switch.

3. Re: Dual Speed Wiring Question

The pump is a A.O. Smith Dual Speed. Model # is STS1152. It's a 240v pump @ 1.5 HP.

I think I followed you through that. So basically, L2 Common has one of the 120v phases connected. Then the switch will connect the other 120v phase to either L1 or A depending on if I want Hi or Lo, correct?

I'm going to assume the neutral won't be wired to anything?

4. Re: Dual Speed Wiring Question

You are correct. It didn't take you nearly as many words to say that as it did me.

5. Re: Dual Speed Wiring Question

Good deal

Thanks for the help!

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