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Polished&Waxed
05-25-2009, 01:05 PM
I want to add some more breakers in my box to go to my garage. I have a ?200 main? (the big one at the top) and all the breakers add up to 200 in the box? can I get a bigger main and then add some 15 or 20 amp breakers? the box itself has a ton more slots that arent being used.

artm3
05-25-2009, 01:50 PM
the mains (lugs & bus bars) are rated for 200A, so you can`t change the MCB



if you have space you can add some CB`s

maybe some already installed are spares?



chances are everything in the box is not on all the time, eg, furnace & AC...

and breakers are only loaded up to a max of ~80% of their rating...most of the time less...



think of a receptacle circuit...they usually have 8 or less receptacles to get to the 80%, yet very seldom are more than a few have something plugged in, or even less on...



how many breakers do you want to add?

what will they serve?



look at your electric bills, see if they tell you your peak demand...this is usually the most power you used in a 15 minute sliding window...



multiply x 1000 and divide by 240...this is ~ the max amps you`ve drawn...

I bet it`s less than 100 A

Polished&Waxed
05-25-2009, 01:59 PM
I have an average daily use in KWH which is like 5-10 on average



I want to add 4+ but 2 or 3 would do.



lights, buffer, steamer, vac, radio, air compressor, extractor im having a tough time with one 15amp right now. hehe

Setec Astronomy
05-25-2009, 02:01 PM
look at your electric bills, see if they tell you your peak demand...this is usually the most power you used in a 15 minute sliding window...



A demand meter on a residential application?

artm3
05-25-2009, 02:09 PM
I have an average daily use in KWH which is like 5-10 on average



I want to add 4+ but 2 or 3 would do.



lights, buffer, steamer, vac, radio, air compressor, extractor im having a tough time with one 15amp right now. hehe





that`s very low usage...

I have a heat pump...no gas, all electric house

last month was 880 or ~30 kwh/day

my highest being 2400 in Jan, or 80 kwh/day...

over 8 hrs (less sleep & work) that equates to 10 kw, or 40 A at 240 VAC...

double that for peaking factor and you still only have 80A...



the only thing that would concern me is the compressor...

what HP? what voltage?

adding a 2 pole for the compressor, and 2 20A single poles should be no problem...

artm3
05-25-2009, 02:15 PM
A demand meter on a residential application?



most of the new type digital meters have it...

it`s very simple, it`s already calculating the load, and integrating/totalizing it...

a couple lines of code and a buffer to store the highest...

reset when read...



aren`t some areas using it as an incentive to lower bills?



whether they set it up to display or put it on the bill is another matter...





Pacific Gas and Electric (PG&E; San Francisco, California) is deploying its SmartMeter program. PG&E contracted with ESCO Technologies Inc. (St. Louis, Missouri, U.S.) to install the TWACS Network Gateway with advanced transponders. With more than 5 million electric and 4 million gas customers, it is estimated the deployment will cost nearly $2 billion. The SmartMeter program will introduce time-of-use rates, demand-response features through programs like Critical Peak Pricing, and provide capabilities such as outage detection and assessment and remote connect/disconnect for electric customers.



here`s a utility that offers residential demand service:

Black Hills Power - Products & Services (http://www.blackhillspower.com/demand2.htm)

Polished&Waxed
05-25-2009, 02:21 PM
http://www.homedepot.com/catalog/productImages/400/c6/c6c16f46-879f-4682-969d-0c74b7d32b99_400.jpg



120volt 15 gal

Setec Astronomy
05-25-2009, 02:23 PM
My utility hasn`t gotten into demand monitoring/charges for residential customers; I`m only familiar with it on an industrial basis.

artm3
05-25-2009, 02:31 PM
My utility hasn`t gotten into demand monitoring/charges for residential customers; I`m only familiar with it on an industrial basis.





it`s still not common, but as utilities replace meters, and costs go up, it will be...

plus, it`s another revenue stream...lol



the next big thing is cell phone communicating residential power meters, reporting automatically to the utility...



techology run amuck :spot