Pump motor wiring

[toddbailey]

Just wondering if having both low and high speed leads hot at the same time will damage the pump motor?

I have a Ao Smith motor pf-30-2n226 3 hp motor and a partly failed spa controller.
When the pump is connected to the pump one connector, the pump only operates on high speed, the low speed circuit has failed.
I can connect the pump to an aux connector and operate the pump normally.
I was thinking to avoid a hefty repair bill (ie replace the controller board) that I could split the low and high speeds connections across the different connectors.
So when the controller calls for circulation, the pump connector is hot, when I want full speed I preass abutton and the high speed line becomes active.

The problem with this is it would be possible to cause power to energize both high and low speed lines at the same time. I need to find out if this will damage the pump motor or not?

 

[jblizzle]

Honestly I am not positive, but it seems like a bad idea.

Is this a 120V or 240V wiring setup? Guessing 240V as that is a large motor ... if so, there should be a common hot line wire and then the low and high speed line wires (which I think you only want 1 hot at a time, but need someone to confirm)

 

[toddbailey]

yup 240 ac one common terminal and a low and a high speed terminal.

 

[Bama Rambler]

You don't want to connect power to the low and high windings at the same time.

 

[toddbailey]

Logically that makes sence, however, I want to find out for certain if it were to happen, would the motor become damaged. I sent an email to ao smith to get the full story.
I suspect the motor would be damaged, so I need a different approach. The spa controler has partly failed, and I get high spped but not low which is also used to circulate.
I'm thinking I can reset the controller to think it only has a single speed pump then use a relay to switch between high and low windings that would be controlled via the aux circuit.

It's a hack to be sure but far less spendy than paying for a new controller.

 

[Bama Rambler]

As long as the relay is 'break before make' (which most all are) you should be fine.

 

[swimcmp]

This is a bad idea I do believe. The control panel is really needing to be replaced. There are several safety switches that you are going to bypass with the setup you are thinking about. Professionally I would tell you not to do it. Personally I would not be comfortable getting in it.

 

[toddbailey]

There are no safty issues in this hack, I am just providing a different way to switch between low and hi pump speeds, If a low presure sensor trips then there is no power being sent to the motor.
The relay will normally be on the low pump speed and activiated ( to high pump speed) when the aux line is triggered. But with out power coming from the main pump circuit, it won't matter if the relay is active or not.

 

[JamesW]

I sent an email to ao smith to get the full story.

Note that A.O Smith no longer makes pool or spa pump motors. They sold those divisions to Regal Beloit in August 2011.