Pentair VS 3HP pump keeps losing power. Proper electrical connections?

[IMV8N]

I'm having a hard time figuring out why my pump keeps losing power. I ran new 10 guage wires from the pump to a 20 amp dual breaker. When I do test the connections at the pump with breaker on I get no reading. I found that if I use two separate 20amp breakers I will then get my 240 at the pump. Why is this? I thought the purpose of the dual breaker was so that both L1 and L2 can use the same breaker? Either way I got the pump running today and while I was standing near it, it shut off again. I open the lid and it show me the error message of "power off" as if the breaker was turned off, but it wasn't. Would anyone be able to offer any suggestions on what I could try to resolve this and also why I can't get 240 off a single dual breaker?

 

[Poolbreh]

It sounds like the breaker is a bad and you are missing a leg. Replace it with gfci breaker. Don’t use two separate breakers. When you take it off, inspect terminal bars for cracks or burns. Make sure power is off whenever working on it and inspecting it.

 

[IMV8N]

It sounds like the breaker is a bad and you are missing a leg. Replace it with gfci breaker. Don’t use two separate breakers. When you take it off, inspect terminal bars for cracks or burns. Make sure power is off whenever working on it and inspecting it.

It's a brand new breaker. I've tried two brand new breakers. Can you elaborate on "and you are missing a leg"?

 

[1poolman1]

Those breakers in your panel are "twin" breakers, not double-pole breakers. What looks like two separate breakers is actually two breakers on a "leg." If you look at the top breakers on each side you will see the middle two are connected, Each one is on a separate "leg." For simplicity, 240v is is made of 120v on one "leg" that is on while the other "leg" is off. We use "alternating current." They switch back and forth to get 240v. If you measure voltage on the top two terminals of those breakers, putting the test lead on each of the two, you will get a 0 reading. Put the lead on either of the terminals and the other on the neutral, or any bare metal, and you will get 120v. Put a lead on the top and third and you will get 240v.

If the bottom-right breaker is the new one, it has both terminals on the same "leg." You need a double-pole, 20amp, ground fault circuit breaker installed in its place with the wires to the pump coming off of each side of the new breaker. It would completely fill the panel.

 

[Poolbreh]

I was just about to say they are tandem and not double pole. You need a gfci breaker. Tandem are for 120v and double pole for 240v

 

[4xWTub]

I've tried two brand new breakers.

I sus[ect that you aren't using the correct breakers. In the photo with the breakers, there is no 'rod' connecting the pair of 20a breaker 'handles'. Those are separate breakers in a single body. You need a breaker that spans both of the buss bars, and the handles should be connected so that if one trips, it forces the other one also.

 

[IMV8N]

Today I learned the difference between a single pole tandem breaker and and dual pole breaker. Thank you all for the replies. I went and purchased an actual dual pole breaker today and my pump is runnning for the moment, hopefully this was the final fix. I couldnt find a GFCI dual pole 20amp breaker though. I just installed the regualr dual pole breaker. My question now is how important is the GFCI one to get and install? I do have a GFCI breaker in my main panel that feeds or controls the pools sub panel. Is this sufficient or do I still need the GFCI dual pole breaker on my pump as well? Also I plan to purchase another similar pump to the VS 240 one. Is it ok to run both pumps on the same 240 breaker?

 

[1poolman1]

What will the total amp load be? It is always best for 1 device per breaker at these loads. If you trip the GFCB in your main panel does all power in the subpanel stop? If so, it would have to be a large-capacity breaker. 60 amp? If not it is likely just for the pool light. Best guess from 500+ miles away.

 

[IMV8N]

What will the total amp load be? It is always best for 1 device per breaker at these loads. If you trip the GFCB in your main panel does all power in the subpanel stop? If so, it would have to be a large-capacity breaker. 60 amp? If not it is likely just for the pool light. Best guess from 500+ miles away.

The sticker on the pump says Max amps 16A. So if it's two pumps I guess that makes it 32?

I tripped the pool GFCI on the main panel and yes everything on the pool sub panel shut off. It's a 50A breaker on the main panel.
I have no more room in my sub panel for another dual pole 20 amp breaker so thats why I ask about running the two pumps off the one. I just dont want to fry anything or break anything. So is it ok to attempt it without ruining anything?

 

[1poolman1]

Conventional breaker sizing is 25% larger than highest load rating of the device you are protecting. A 20a breaker on one pump is maximum. Running two pumps with a 16a rating each on one breaker will likely cause a lot of nuisance tripping.

 

[IMV8N]

Conventional breaker sizing is 25% larger than highest load rating of the device you are protecting. A 20a breaker on one pump is maximum. Running two pumps with a 16a rating each on one breaker will likely cause a lot of nuisance tripping.

Thank you for all the advice!