ran out of circuits breakout box?


Old 11-01-10, 01:08 PM
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ran out of circuits breakout box?

I'm purchasing a house that's breaker box is full and I need to install some more circuits in the home. Can I just install a breakout box then add more circuits or do I need to have the electric company come out and turn off the power so another panel can be installed? I'm looking to add about 6 20 amp circuits in the home. Mainly for my servers, aquarium, garage, home theatre, and wood working area. I've been starting with Home Automation with insteon and these circuits project interference so is it possible to have them powered completely seperate from the main panel?
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Old 11-01-10, 01:43 PM
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If the panel can support them, tandem breakers (two breakers in the space of one) are the cheapest option. However not all panels can use these.

The second option would be to add a subpanel adjacent to the main panel for more space. This is a good way to go if you just need more space for breakers, but not a significant increase in power. The cost is quite a bit less than replacement of the main panel.

The most expensive option is to have the main panel replaced. This may be necessary if you need more space and more power, such as to support a new spa, large machine, or tankless water heater. It may also make sense to go this route if the existing panel is obsolete or in poor condition. Sometimes this would be an advanced DIY job, but most people should hire an electrician to do it.
Old 11-01-10, 02:03 PM
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So I'd basically get a tandem breaker then run the power from that to the subpanel? Do they make things like 100amp tandem breakers? I'm afraid we might need more power. I really can't have the aquarium or servers turn off because I'm using the table saw and a friend's using the radial arm saw.
Old 11-01-10, 02:25 PM
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No, tandem breakers may be an option to replace your existing breakers. Tandems allow two breakers to fit in the slot of one, essentially increasing the available slots in the panel. Not all panels can accept this type of breaker, however so we would need to know the panel make and model or a couple good pictures to give you more guidance on this.

There is a process called "demand load calculation" used to determine if your existing service can supply enough amps for your need. Usually an aquarium or small woodshop is not enough to require an upgrade, but if you have an old service it could be a problem. You can Google for information how to do this calculation or post back the current size of your service, size of the house and list all of the major electrical appliances (existing and planned) we can help to figure it out.
Old 11-01-10, 04:45 PM
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Main breaker is SquareD QO e8 150 amp

I figure min needed is:

20 amp server room
20 amp wood working
10 amp aquarium
10 amp garage
10 amp home theatre

3000-3500 sq ft 4 bdrm home

electric water 50 gal
electric range
electric dryer
A/C but gas heat

I could consolidate some circuits and I know currently the aquarium, server, and home theatre are on seperate panels. The main problem is the aquarium runs about 500w at night and 1000w during the day and server's run 1000w+ 24x7. I'll likely be using a saw, while the compressor(in garage) is on, while listeing to whole home music (home theater).
Old 11-01-10, 05:25 PM
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If the circuits are properly designed for the loads they are expected to handle there should be no problems. If the circuit for the workshop trips it does not mean that it will take out the aquarium, unless they are on the same circuit.

Look at the loads and plan approppriately.

Yes you can get a 100 amp 2 pole breaker, but not a tandem 100. It will be costly and you don't need that much power anyway for the subpanel.

The smallest circuit you will be installing will be a 15 amp circuit. This does not mean that you will be using all 15 tho.
Old 11-01-10, 07:15 PM
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It sounds like your best option would be to install a subpanel with a 60A feeder. Move a few of the smaller loads into the new sub and leave the larger loads in the main. You may want to purchase a 100A panel and feed it from a 60A breaker.

As long as you're comfortable working in the main panel (remember, the mains are always live), it's certainly an (advanced) DIY project.

See the sticky at the top of this forum for an overview of installing a subpanel and of course if you have any questions there are always people here to help!

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