- Location
- Tennessee NEC:2017
- Occupation
- Semi-Retired Electrician
If you haven't seen this thread
http://forums.mikeholt.com/showthread.php?t=177375
you might want to look at it before reading this one to know what I'm talking about.
Customer was complaining of feeling a shock when exiting the pool while holding the handrail.
So I went to check the bonding around the pool and pool equipment. Here is what I found.
I had a "neutral to earth voltage" (NEV) of 1.45V
I had the same (very near) voltage at the pump motor, heater, salt generator, & timer
At the pool I had practically the same voltage in the water.
Same at the ladder
But at the handrail I only had .7V
So I checked from the water to the rail and got around .7V
That is where they were feeling the shock, so I figure they were getting from 1/2V - .7V. That checks with the difference in the NEV from everything else and the rail.
I did show some continuity to the rail but it was a higher resistance than every other item bonded.
To confirm this I connected a coil of #8 copper (about 15') to the rail and dropped the remainder of the coil into the pool. I checked the voltage again at the rail and it brought it back up to the level of everything else.
I suspect either loose connection in the cups or deterioration. Customer said that the pool company said they had some way of replacing the mounts/cups at the rail. But he is not going to have them do it until they replace his liner next year.:slaphead:
I told him the only thing I knew of was to bond the rail to the water the way I did but with something a little neater. Told him to keep that bonded until the rail mounts are replaced and he agreed.
Anything else I should have done?
http://forums.mikeholt.com/showthread.php?t=177375
you might want to look at it before reading this one to know what I'm talking about.
Customer was complaining of feeling a shock when exiting the pool while holding the handrail.
So I went to check the bonding around the pool and pool equipment. Here is what I found.
I had a "neutral to earth voltage" (NEV) of 1.45V
I had the same (very near) voltage at the pump motor, heater, salt generator, & timer
At the pool I had practically the same voltage in the water.
Same at the ladder
But at the handrail I only had .7V
So I checked from the water to the rail and got around .7V
That is where they were feeling the shock, so I figure they were getting from 1/2V - .7V. That checks with the difference in the NEV from everything else and the rail.
I did show some continuity to the rail but it was a higher resistance than every other item bonded.
To confirm this I connected a coil of #8 copper (about 15') to the rail and dropped the remainder of the coil into the pool. I checked the voltage again at the rail and it brought it back up to the level of everything else.
I suspect either loose connection in the cups or deterioration. Customer said that the pool company said they had some way of replacing the mounts/cups at the rail. But he is not going to have them do it until they replace his liner next year.:slaphead:
I told him the only thing I knew of was to bond the rail to the water the way I did but with something a little neater. Told him to keep that bonded until the rail mounts are replaced and he agreed.
Anything else I should have done?