Two speed Electric motor question

[beowulf]

This seems to be the most logical forum in which to post this - though not actually a rural living issues.

Anyway, we have a 2 speed pool pump controlled by a panel with a fast and a slow speed button. 230V.

A bearing went out so I unhooked the pump and took it in for repairs at a local shop. But when I reinstalled the pump, the pump works with the high speed button but when I hit the slow speed button I only get a moderate humming sound. I am fairly confident I rewired it correctly - one red, one black, a white and a ground. But maybe not?

After this happened I reversed the red and black wire connections (though I did not think this could be the issue) and then the slow button worked to turn it on at a fast speed and the fast button only caused the humming sound.

Most likely it is my fault somewhere but not sure so looking for help. BTW - I checked the breaker and it seems to work - it consists of two 20 amp breakers which were once bound together but that plastic piece broke - but I throw both together now until I fix that.)

Looking for ideas, things to try, the bad news. . . .? I will try to call the pump manufacturer as well. Thanks for any suggestions.

 

[the old grind]

Sounds like another wire-switch will get you there. (DAMHIK) Say if white and red were 'hota' vs white & black.

NEC specs are for external wiring, but not always followed inside some equipment. At least you didn't have brown, orange, and yellow, too.

 

[Roadworthy]

Take the motor back to the shop. Explain to them it is a two speed motor and ask them to please identify what power level connects to which wire. Normally the two colored wires (red and black in this case) are "hot" and white is neutral. While checking things out identify your power lines going to the pump. It is possible your line colors do not follow the electrical code. Something may even be swapped somewhere between there and the panel - perhaps in a junction box along the way.

 

[beowulf]

Roadworthy - thanks for responding. The only thing that was disconnected in order to take it to the shop were the wires going into the motor. Two hot (red and Black) and the neutral and a green ground. I am almost certain I reconnected the wires in the same spots - the only thing that made me start to doubt this was that the low speed did not work. So, I switched the red and black leads - same result - no low speed except that then the low speed button turned on the high speed, and the high speed button resulted in the same humming sound.

All connections are tight at the motor and at the control box. I also tried switching the neutral with the black and then the neutral with the red - nothing starts on either button in either of those scenarios.

I will take it back to the shop - likely they can tell me what the problem may be. I posted the question generally on the Internet and found discussions of this issue - i.e, only the high or only the low speed working on a two speed pump. Some comments there were beyond my pay grade to understand, but others said it is likely a faulty relay - something that is apparently important on a two speed pump and something that would cause this.

 

[the old grind]

Did the controller die and not the pump to begin with?

Fingers crossed that the shop will get you going.

 

[beowulf]

Did the controller die and not the pump to begin with?

Fingers crossed that the shop will get you going.

The old grind - thank you for responding.

The reason I took it to the shop was because one day it started screeching loudly - very very loud. So I figured it was a bearing issue - both speeds ran then - but it screeched on both speeds. The day before the screeching I noticed the sound of the pump was just ever so slightly different and mentioned that to my wife. The shop said they replaced the bearings and the seals.

I forgot to mention though, that to test the control panel I bypassed the high and low speed switches in the control box by connecting the load and lead wires directly and had the same results - the pump worked when connected outside of the control box on high, hummed when connected outside of the control box on low.


AND forgot to mention also: If I push the fast speed button at the same time I push the low speed button and then let go of the high speed button, the pump works on low speed - which otherwise does not work just by pushing the low speed button. So, confusing.

 

[workinonit]

I think that white wire is actually your low speed winding. Look at the nameplate on the motor and verify that the motor has a high and low speed winding. 240 VAC motors don't have a neutral.

 

[Industrial Toys]

^ Could be. I would simply ask the shop. No offence, but people experimenting with connecting various wire schemes and then trying different ones when that doesn't work , is a recipe for damage.

Sounds like the starting capacitor or start winding is somehow messed up if you can run the other speed when starting it on the other speed.

 

[beowulf]

^ Could be. I would simply ask the shop. No offence, but people experimenting with connecting various wire schemes and then trying different ones when that doesn't work , is a recipe for damage.

Thanks for suggestions. No offence taken - I have to agree with you and those thoughts were also mine as I experimented a bit.

 

[RoyKing]

post a pic if you have no wiring diagram