Hey guys,
I was called to look into some bad underground at our city park.
They have a 200amp panel in a pavillion that feeds underground to a bath house and another smaller pavillion.
The city man said when they turned on the breakers they heard a loud buzzing or hammering sound, meter was spinning erratic then it all stopped. No power to bath house or pavillion 2.
He said he measured voltage at the breakers and had 240 and 120 to ground, which I verified.
Then he said they were digging right after this happened and the ground was pretty wet, one side of the hole was noticeably warmer than the other.
Why they were digging right in the spot of the fault I don't know. This is just what he told me.
So I started digging and found the feeds. all were severed in half.
So I returned today with buttsplices and heat shrink tubing. spliced all then megger tested.
NONE of the underground lines read over 3Megs, they were reading between 1 and 3.
I remember from reading John's posts that he looks for 100Megs. I set my megger alarm for readings less than 5M.
So what's up? immenent failure? I turned them on anyway and measured voltage and amped. All Ok and functional when I left.
I'd really like to get a handle on megger readings besides the obvious dead short.
I was called to look into some bad underground at our city park.
They have a 200amp panel in a pavillion that feeds underground to a bath house and another smaller pavillion.
The city man said when they turned on the breakers they heard a loud buzzing or hammering sound, meter was spinning erratic then it all stopped. No power to bath house or pavillion 2.
He said he measured voltage at the breakers and had 240 and 120 to ground, which I verified.
Then he said they were digging right after this happened and the ground was pretty wet, one side of the hole was noticeably warmer than the other.
Why they were digging right in the spot of the fault I don't know. This is just what he told me.
So I started digging and found the feeds. all were severed in half.
So I returned today with buttsplices and heat shrink tubing. spliced all then megger tested.
NONE of the underground lines read over 3Megs, they were reading between 1 and 3.
I remember from reading John's posts that he looks for 100Megs. I set my megger alarm for readings less than 5M.
So what's up? immenent failure? I turned them on anyway and measured voltage and amped. All Ok and functional when I left.
I'd really like to get a handle on megger readings besides the obvious dead short.
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