Can someone explain what the amp ratting on electric breaker box means. I
think mine is 100 AMP. Is that a limitation of the box or the power coming
in to my box? What does it take to upgrade to get more ampage? My house is
full of electronics including 2 fridges, 1 freezer, 2 AC units, plus tons of
DJ / computer equipment. I am always seeing voltage drops and I am afraid
its just the entire power system is inadequate. What is involved in
upgrading my system?
When do you see voltage drops? When some big appliance, like A/C
kicks in? Keep in mind that it is not unusual, especially in hot weather
when you and your neighbors on the same transformer, are all using a lot of
power. The problem me be outside your home.
What is the rated amps for those two A/C units?
I wound not be too quick to upgrade your power. To do that you will
need a new panel and likely a new drop from the electric companies
transformer. It can be expensive.
The limit is set by the size of the wire feeding your house, and the main
circuit breaker. For most houses, 100A is adequate and has been for many
years. Central Air being one of the larger uses, followed by an electric
range, then a dryer.
There are other limitations of the system though. You can have 200A or 600A
coming into the main box, but if the distribution is a bottleneck, you will
still get voltage drops on a given line. I have about the same number of
"stuff" as you have, but add a wine cooler too, plus 3 AC units total. .
The motor driven appliance take a lot of power compared to the electronics.
When the AC compressor kicks in, I do see a slight dimming of the lights ON
THAT circuit for a second.
You really need to check out how many breakers you have, what is on a given
circuit, and, what is the real voltage coming in from the street. I get a
full 120v most of hte time, but if you are some distance from a sub-station,
you may be getting less, especially in the summer. That adds to the
You can buy a volt meter fairly cheap. That would be my first step. Voltage
can and will vary in many places.
Then I'd look at the distribution to wee what is on each circuit. In older
houses, it was common to have three for an entire house, where 12 - 16 is
not uncommon now. If a new box was installed in an older home, it may have
been difficult or impossible to break down the lines to multiple circuits.
Well I have one larger AC not sure of the AMPs but its one of the larger
window models. What I did was convert an old 220 line that was under that
window to 110. Changed the breaker and the box on the wall. So it has its
own direct line with nothing else attached. What happens is my backup ups
system trigger and the lights dim every time the AC kicks in. Since that
has its own circuit I figured it was the main power that was not handling
the current. I also notice the same affects when the microwave is used and
other appliances kick in that are on diffent lines.
I took a GFI tester and tested all my outlets including the one I converted
and they are said good except for one that had a bad ground but I don't use
Not sure what to do next.
I'd try connecting that air conditioner to the other leg in your panel
(move the breaker down one slot usually does this) in case the total
load is imbalanced and the grounded service conductor (neutral) is doing
too much of the work.
I'm probably wrong, but it's an easy test.
Some years back, I had this problem. The local electric company
(central NJ) nicely put a recording volt meter on my line. They
re-routed me to a different transformer. There was building in the
area, and additional houses made a difference. I was out at the end of
the drop. No cost to me, and simple answer.
I'm suspecting the pole transformer is not handling the load. I'd
call the electric company and have them do some tests it.
You could also throw a meter across your mains (wires entering the
house), but then you got to sit there and watch it. The power company
usually has a recording meter. I am not sure exactly how they work
but somehow they record the voltages during a period of time. That
sounds like a tool I'd like to own, but I can imagine the price.
Hey, I like the sound of that.....
How does it record the data on the computer?
Does it create a graph, or is it a text file with the time of day and
voltage reading, which is read at pre-determined intervals?
That is the total amps available at 240v. If you have gas appliances
like the stove, water heater and furnace this might not be
unreasonable. The A/C units are probably the biggest load. To upgrade
you will need a new meter base, new service panel and new wiring,
possibly all the way back to the pole.
YMMV on cost, depending on where you live.
Your use does not seem excessive from what you describe, I used to
double that usage from your description. You need to do your own energy
audit to see what you realy use, a Kill-A-Watt and good clamp on digital
amp meter is a good place to start. I would guess upgrading to 200a you
are looking at 1-2000$. Your voltage drops could be individual circuits
being overloaded. Maybe you just need things split up and a few new
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