Can water bonding introduce electrical current?

[Transy416]

I just watched Swimming Pool Bonding and at the 1:36:18 mark, brought up was that if the pool pump faulted to the #8 pool bonding on the metal case and the breaker did NOT trip, then the entire equipotential system would be at 120v. Pointed out was that a swimmer or anyone walking on the WET pool deck would not be shocked UNLESS they touched something of potential difference.

My question is this…in this scenario, how would one KNOW a potential difference exists befote something fatal happens? That is, if someone either exits the pool and walks beyond the perimeter bonding loop, or someone comes from outside the pool area toward the perimeter bonding loop, then wouldn’t they be killed when crossing the difference in voltage potential? If true, then again how does one know a potential difference exists before something fatal happens?

 

[ajw22]

If true, then again how does one know a potential difference exists before something fatal happens?

You don't. Which is why the NEC requires multiple levels of safety in many ways. It would take the Swiss cheese holes to line up in multiple failed safety layers to get injured.

That is why people should install GFCI CBs as required by the NEC even though their systems are grandfathered.

 

[mas985]

I just watched Swimming Pool Bonding and at the 1:36:18 mark, brought up was that if the pool pump faulted to the #8 pool bonding on the metal case and the breaker did NOT trip, then the entire equipotential system would be at 120v. Pointed out was that a swimmer or anyone walking on the WET pool deck would not be shocked UNLESS they touched something of potential difference.

My question is this…in this scenario, how would one KNOW a potential difference exists befote something fatal happens? That is, if someone either exits the pool and walks beyond the perimeter bonding loop, or someone comes from outside the pool area toward the perimeter bonding loop, then wouldn’t they be killed when crossing the difference in voltage potential? If true, then again how does one know a potential difference exists before something fatal happens?

I am not sure about your house but mine has two sets of breakers. Several for the equipment at the pad plus a main breaker at the power company premise entrance. So both breakers (+GFCI) would have to fail and both fail in a closed position which is highly unlikely.

Some power systems also place breakers or fuses at the block transformer as well so there are several layers of redundancy.

Remember that the bonding wire is connect to house ground which is connected to house neutral so a direct short like that would draw a lot of current. Should such a remote possibility happen and the lines remain energized, the high current flowing through the wires would get them very hot and the insulation would start burn so you would definitely smell that and it would perhaps start a fire in the house depending on the wiring routing.

 

[ajw22]

Should such a remote possibility happen and the lines remain energized, the high current flowing through the wires would get them very hot and the insulation would start burn so you would definitely smell that and it would perhaps start a fire in the house depending on the wiring routing.

It is good that the Fire Department would be called to get the electrocuted person to the hospital.

 

[Transy416]

Thanks. All my outdoor equipment is fed by GFCI breakers, and receptacles are GFCI’s as well.

I suppose if I wanted to be extra cautious, I could also replace the subpanel main breaker in the house (which feeds the pool and everything around it) with a GFCI main breaker.

 

[mas985]

I suppose if I wanted to be extra cautious, I could also replace the subpanel main breaker in the house (which feeds the pool and everything around it) with a GFCI main breaker.

Putting GFCIs in series can be problematic as some units have a self test which the GFCI upstream could detect as a fault.

You would be better of just periodically testing the GFCI to ensure proper operation.