Changing Entire Panel (Details)

**molo** · 09-04-2011, 11:14 AM

Hello,

I have an older 100 amp panel. I am considering changing it. The panel serves a 3-bedroom home. Is it within code to use another 100 amp panel? Is it required to go larger?

Thanks,
Bill

**cacher_chick** · 09-04-2011, 12:24 PM

100 amps in a 3 bed would be pretty common. If you run the numbers you will probably see that it is fine, which saves you from having to replace the feeders. I would look for a minimum of 24 circuit capacity for a 1000-1500 sq home.

If you have a lot of devices requiring 220V- electric water heater, air compressor, welder, hot tub, central air, cooktop, oven, etc, etc, then I would seriously consider going to 150 or 200A with more space for additional circuits.

Remember, you only want to do this once.

**jadnashua** · 09-04-2011, 12:34 PM

If you ever want to remodel the kitchen, bath, or upgrade anything, you'd probably want more room in the panel than a typical 100A one would provide. Now, you may not need more actual power capability, but generally, you'd use a larger supply on a larger panel (you could always buy a 200A main panel, but substitute a 100A main breaker to match your supply). Most modern kitchens have all sorts of power devices: microwave, frig, stove, vent, dishwasher, the counters, garbage disposal. Now, they all don't need their own dedicated supply branch, but many of them are recommended to have them by the appliance manufacturer. It also makes life easier when it comes time to do any repairs - you can shut only that one thing off while you deal with the problem without impacting potentially numerous other things. Modern codes often require more circuits, but replacing the panel would be grandfathered, most places meaning you wouldn't need to run new circuits unless you were also remodeling say the kitchen. It would be nice to acutally have the space for them, though.

**molo** · 09-04-2011, 04:43 PM

1.Yes, I recently saw a panel in a new Homewood Suites room (with kitchen). It appeared there was a circuit for nearly every appliance and outlet!

2.I like your point about using a 200 amp box and putting a 100amp main allowing for upgrade to 200 amp in the future.

3. per cacher-chick's statement; Is there enough room for 24 circuits in a 100 amp box?

Originally Posted by jadnashua

If you ever want to remodel the kitchen, bath, or upgrade anything, you'd probably want more room in the panel than a typical 100A one would provide. Now, you may not need more actual power capability, but generally, you'd use a larger supply on a larger panel (you could always buy a 200A main panel, but substitute a 100A main breaker to match your supply). Most modern kitchens have all sorts of power devices: microwave, frig, stove, vent, dishwasher, the counters, garbage disposal. Now, they all don't need their own dedicated supply branch, but many of them are recommended to have them by the appliance manufacturer. It also makes life easier when it comes time to do any repairs - you can shut only that one thing off while you deal with the problem without impacting potentially numerous other things. Modern codes often require more circuits, but replacing the panel would be grandfathered, most places meaning you wouldn't need to run new circuits unless you were also remodeling say the kitchen. It would be nice to acutally have the space for them, though.

**cacher_chick** · 09-04-2011, 08:20 PM

Here's a list of available Square-D QO panels to help you see what is available.

http://www.schneider-electric.us/doc...in-breaker.pdf

**jwelectric** · 09-05-2011, 05:47 AM

Size the service by the calculated load that the service will see.

I have always used a 30/40 panel of which ever brand name I was using at the time. This panel will hold 30 1 inch breakers or up to 40 by using the mini breakers.

**Jim Port** · 09-05-2011, 07:32 AM

Adding a subpanel is also an option when only more breaker spaces are needed.

**Lakee911** · 09-05-2011, 04:36 PM

You should really run a load calc to determine the correct size. For an average 3 bedroom all gas house 100 is probably fine.

Jason

**molo** · 09-06-2011, 08:58 PM

Decided on a Cutler Hammer 100amp BR model with 30/30 (with 6 20 amp breakers and a double-pole 30 amp breaker) $81
The electrician said it was fine, and it would be easy to find breakers for it.
Question: Can this panel be updated if necessary in the future to a 200amp by buying a 200 amp main breaker? My guess is no, but I'm hoping the pros can answer this. (I asked the electrician and he rattled off an answer that I didn't quite follow)

Thanks,
Bill

**jwelectric** · 09-07-2011, 05:17 AM

No! .

**nukeman** · 09-07-2011, 05:50 AM

You could go the other way, though. It would cost a little more for the 200A panel and then you'd have to also pickup a 100A main breaker. The 200A breaker that comes with the panel could be kept on hand for a future upgrade to the service.

**jadnashua** · 09-07-2011, 04:00 PM

In theory, the bus bars are sized for the max load, so a 100A panel's bus bars and other internals would be too small to support 200A at full load. WHether that is always the case is another issue, but the labeling would make it a violation, regardless.

**mrmedic** · 09-07-2011, 04:45 PM

If you are thinking of getting a new 100 amp box, Most of the time the only difference in changing out the 100 and going with a new 200amp might be the down feed wire and meter box. Price should not be that much different. At least around here it isn't. What was the electrician going to charge for the new 100 amp set up? I would just go with the new 200amp.