about grounding values

[James Sentman]

On Oct 9, 2013, at 4:31 PM, George Handley <ghandley at kc.rr.com> wrote:

> As a further indication that I do have a poor ground, I can report that when our AC goes on, some lighting circuits will blink. I'd seen this for years here, but drew no connection.
> 

I am interested in this... at the house here there is no flicker of the lights at all when the AC comes on, but at a good friends of ours house there is a considerable dimming of his lights (which I am slowly helping him automate) when his AC cycles on. I never really paid it much attention thinking that his entire service must be smaller or something to cause such a dip in the overall voltage when starting up the compressor. 

I can't quite get my head around how a bad ground could cause your lights to flicker when a large load is applied? Whats the story with that? I cam imagine a loose neutral perhaps? Or just an undersized feed, or perhaps the voltage is low at the end of your run anyway so it has less overhead? But help me to understand how a bad ground can cause it?

Now that I've asked the question I can wax about my own experience with the electric company like this. Some years ago I started to notice a regular, about every 40 seconds flicker in the lights. All the lights. I put my own meter on any socket and I could actually see the dip in the line voltage almost perfectly regularly every 40 to 45 seconds. It lasted just enough time for the meter to make one low reading and then went back to normal. This drove me crazy! I turned off every circuit breaker in the house and measured at one that has only a single outlet at the meter on it and the flickering continued. I called the electric company and they thought I was crazy, but happily sent out a guy with a logger device who logged it over a few days, and then they ran me an entirely new underground feed wire from the transformer to my service drop entrance. I have no idea what was going on underground, but that fixed it. So stranger things have happened :)

Thanks,
 	James


James Sentman                       http://sentman.com		http://MacHomeAutomation.com