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In alt.engineering.electrical Michael A. Terrell wrote:
| wrote:
|
| In alt.engineering.electrical Michael A. Terrell wrote:
| | wrote:
| |
| | In alt.engineering.electrical Michael A. Terrell wrote:
| |
| | | The central air kicks on without my lights dimming, and I am in North
| | | Central Florica.
| |
| | I bet it's on its own branch circuit, too.
| |
| |
| | So what? The meter is on a pole on one side of the driveway ( two
| | feet from the property line, because Progress Energy does not allow
| | drops to cross a driveway anymore.), and an outdoor breaker box is on
| | the remaining four foot stump of the old pole on the other side of the
| | paved drive, about 40 feet away. The 60 A breaker for the AC is in that
| | box, along with the 100 A main breaker that is used as a disconnect for
| | the house. That box is over 125 feet from the pole pig, on a 150 A
| | service. That box also feeds another underground line to the laundry
| | building,, and well pump. The main breaker box for the house is another
| | 20 feet from the outdoor box. Now, tell me how it can have no effect on
| | the line voltage. I still see very little flickering, usually only on
| | hot summer days when everyone in the subdivision is using the AC and
| | their kitchen stoves at the same time. That is usually followed by a
| | blown 60 A fuse in the 7200 volt line, feeding my street.
|
| If it were not on its own branch circuit, that would (in addition to being
| a code violation) more likely cause other stuff (whatever else is on the
| same circuit) to experience dimming. The fact that it is onis own branch
| circuit doesn't mean there isn't a big voltage drop. But only the A/C would
| be getting it, and it wouldn't matter (much).
|
| It can have no (or very little that cannot be noticed) effect on the line
| voltage because you have good wiring and the transformer has a high enough
| capacity and low enough impedance. This is stuff you know.
|
| Blowing a 60 amp fuse at 7200 volts is not a small neighborhood.
|
|
| 48 lots, 47 with homes. That gives 7200*60/240 or 1800 A @ 240 V for
| 47 homes gives an average 38.29 A per home which is the reason that fuse
| can blow more than once a week, along with it's explosive discharge that
| sounds like a shotgun every time it blows.

Yup, big neighborhood. It wouldn't take much after 47 home central A/C's
are running to go over the fuse rating. Any guess what the curve on that
fuse is? E.g. how long can you go at 105%? 125%?

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