Thanks, I didn't know those backups could shock you on the battery side.
In my demolition work, I have to be very careful about electricity. I had to take out a large transformer on top of an office building. The power company had turned off the whole thing, everything shut down. Luckily, I had just seen on Discovery channel the night before a neat little electricity "sniffer" that you hold near wires and it can light up and buzz when there is current on. I got one at Home Depot that morning and was happy to try it out. The thing went off and kinda scared me. Turns out that this one transformer was tied in to a completely different power source and was fully functioning. It could have been bad.
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