Michael Leach wrote:
> So back to my question, if you have only 200amp service then you have
> problems? Does this mean you need two electric meters from the power
> company (i.e. two services). Or do they just rip out the main 200amp
> main breaker add a 300 or 400amp breaker and jack up the power to your
> house from the transformer on the pole?
I suspect it depends on factors such as local building codes, and the
state of the existing electrical service. I recently added a reasonably
large attached garage/shop to my house. The local building code
required that there be only one service entrance (maybe they're afraid
of illicit duplexes), so I asked the power company about my options. A
power company rep came out and took a look (before any construction had
begun), and advised that the existing transformer and (underground)
service lines were sufficient to support 400A service, so "all" I needed
to do was to replace the existing meter base with a 400A
disconnect/meter, and wire both the existing house breaker panel and the
new garage/shop panel as sub-panels (i.e. install 4-wire runs from the
disconnect/meter to both of those panels). Now, I'm not entirely
convinced that either the transformer or the service wire will _really_
support 400A, but that's their claim and if there's a problem, it's
PP&L's problem, not mine (yes, everything was permitted and inspected).
> Does the tranformer have enough
> amperage to supply your house and your neigbors house (i.e they usually
> share transformers between two houses) and your shop?
Again, this will likely vary by locale and age of installation. The
newer installations in this area appear to dedicate a transformer to
each residence.
> The moral to this story is I don't
> beleive any one person shop is going to ever match what my friend has
> accomplished with one 200amp service.
The worst-case load I considered was:
electric force-air heat on (Natural Gas is not an option for me)
22A ("5 hp") Compressor on (due to minor air leaks and/or catch-up)
50A welder on
lights
I got very tired of switching between the welder and compressor in my
previous shop. I figured 100A would be enough, but there wasn't a
significant cost difference between a 100A panel and a 200A panel
installation after the service entrance upgrade.
Harry Phinney harry@cv.hp.com
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