2 single-pole breakers (untied) for 240vac circuit

[jeff47]

Hello,
I was checking my breaker box during the process of shutting down my pool for the season. My pool equipment (pumps, timer) run at 240v. When I went to turn off the breaker, I realized it was two single pole breakers that were independent. That is, there was no handle tie so they could trip independently.

They are breakers 27 and 29, both are single pole 15amp Square D QO.

If I trip both, my voltmeter at the pump reads 0v. If I turn on either 27 or 29 alone, they read ~5v. If I turn on both 27 & 29, I get the expected 240-250v.

Two questions:
1) Shouldn't there be a handle tie between 27 & 29, or a double pole breaker?
2) Why do I see 5v when only one breaker is active? I was expecting 120v.

I did not install these breakers - we are fairly new to the house so the system predated us. But I'm puzzled by the setup.

 

[ipf]

What are you saying?....that it should be double pole and switching neutral as well as live?

It sounds like a 3 phase board (27 and 29) , in which case you are talking 400volts.
Getting on a bit, too (15 amp).

Photos and a decent explanation would help.

 

[Lucien Nunes]

OP is in the US. With either breaker on, you would see 120V from hot to both neutral and ground, but no significant voltage from one hot to the other since the circuit is interrupted by the other breaker. The small voltage you are reading results from capacitive leakage to ground from whichever hot wire is not energised, which allows a tiny current to flow through the input of your meter amd give a slight indication.

Yes the breakers should be linked so that the circuit is not left energised from one hot while appearing to be dead.

 

[ipf]

OP is in the US. With either breaker on, you would see 120V from hot to both neutral and ground, but no significant voltage from one hot to the other since the circuit is interrupted by the other breaker. The small voltage you are reading results from capacitive leakage to ground from whichever hot wire is not energised.

Just realized, never looked just baffled.

 

[jeff47]

OP is in the US. With either breaker on, you would see 120V from hot to both neutral and ground, but no significant voltage from one hot to the other since the circuit is interrupted by the other breaker. The small voltage you are reading results from capacitive leakage to ground from whichever hot wire is not energised, which allows a tiny current to flow through the input of your meter amd give a slight indication.

Got it, thanks!

 

[jeff47]

Just realized, never looked just baffled.

Sorry, should have specified!

 

[ipf]

Sorry, should have specified!

I should have realized, with some of your terms. No Prob.

 

[Megawatt]

Hello,
I was checking my breaker box during the process of shutting down my pool for the season. My pool equipment (pumps, timer) run at 240v. When I went to turn off the breaker, I realized it was two single pole breakers that were independent. That is, there was no handle tie so they could trip independently.

They are breakers 27 and 29, both are single pole 15amp Square D QO.

If I trip both, my voltmeter at the pump reads 0v. If I turn on either 27 or 29 alone, they read ~5v. If I turn on both 27 & 29, I get the expected 240-250v.

Two questions:
1) Shouldn't there be a handle tie between 27 & 29, or a double pole breaker?
2) Why do I see 5v when only one breaker is active? I was expecting 120v.

I did not install these breakers - we are fairly new to the house so the system predated us. But I'm puzzled by the setup.

My friend you need to go to Home Depot or Lowe’s and buy a 20 amp double pole GFCI breaker. All pool pumps and receptacles need to be GFCI breakers

 

[pc1966]

All pool pumps and receptacles need to be GFCI breakers

As above! Listen to @Megawatt 's advice here!