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Mike

On Tue, 22 Jan 2008 12:19:32 -0500, wrote:

On Mon, 21 Jan 2008 16:34:20 -0600, Steve IA
wrote:

If you have more comments/questions, fire away

Steve

To add to what has been said, I would still be concerned about the
mysterious days when power spiked. There is a 90% chance that it is
explainable, but I'll relate what happened when we first moved into
our 1960s house in Florida.

The house had a 150 amp entrance. I didn't give a second thought
about that, since it had obviously worked for over twenty years. It
also had an seven year old heat pump, a pool pump, a sprinkler pump,
lots of incandescent and halogen lighting, an electric dryer,
dishwasher, and some other lesser loads.

During the first summer, I noticed that our electric bill was a lot.
I had no way of being sure why this was the case, so I began poking
around. When I went outside near the meter, I could smell something
hot, like hot electric wire insulation. I then felt the breakers,
which felt a little warm but fine, then moved on to the meter, and
discovered that the conduit leading from the meter box to the breakers
was too hot to touch.

I called in an electrician, and he was able to open things up. The
aluminum wire between the meter and the breaker box had been heated to
a point that it had begun to seriously corrode and add resistance of
its own, and had _almost_ burned away enough insulation between the
wires to create a direct short.

What had happened? The age and type of the wiring was, of course, a
factor, but the issue we had not considered was that during the summer
we might run all of the major power users at the same time. The pool
needed cleaning, it was hot in the house, the lawn was getting dry,
and because we were sweating and drinking lots of water, the laundry
and dishes were being done, all during the late afternoon. The
_cumulative_ draw was enough to damage the connection to the aluminum
wire and the added resistance was overheating both the connection and
wire.

Had I not been sniffing around, we would have had an electrical fire
at a spot where it would be impossible to shut off the current without
either the fire or power department breaking into the transformer box,
and we likely would have had severe damage to the house.

Once the wire was replaced and connections repaired, our power usage
went down by a significant amount.

The moral of the story? Don't let those high power usage days go
unchallenged.

No, the moral is, you just wrote a load of total bull****.

If you have a high resistance joint anywhere in your supply then total
power consumption will always fall. Hot joints in extension leads
are just the same, you'll loose 3/5 of 5/8 of bugger all in a normal
joint and if its resistance rises you'll loose more but the volts are
dropped across that high resistance joint and therefore the downstream
loads will always use less. If downstream devices use switch mode
supplies (such as computers or tv's) then the consumption of those
devices will stay almost the same

You could have a joint in your supply line that glowed bright red in
daylight and if anything it would reduce the consumption of your
washing machine, dishwasher and fridge, and accordingly reduce the
reading on your electricity meter. If the high resistance joint was
on your side of the meter then, with the exception of switch mode
supplied devices you'd consume the same overall amount of metered
electricity but the high resistance joint would usually waste that
heat.

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