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Breaker Panel Question

So I am almost out of space on my main panel and I have a few circuits to add. I have decided to have my main panel replaced but when looking at new panels I find specs that define the number of spaces (easy enough) and the number of circuits. Whats the difference?
Example: 100 amp 20-Space 30-Circuit

Re: Breaker Panel Question

It means the buss in the panel is rated for 100A, it has (20) 1" spaces but will accept up to (10) 1/2" breakers.

If your existing SE panel is 200A (typical home) and not overloaded, you may be able to add the panel , you mentioned, and have it fed by a 100A breaker in your existing panel.

This could save you a lot of money and downtime.

Maurice Turgeon, thesemi-retiredelectrician.com

Re: Breaker Panel Question

so the 100 amp service limit defines the max current draw for the house

the 20 space limit defines the max number of 1" breakers

the 30 circuit limit defines the max number of circuits where I can not exceed 30 breakers when using any combination of 1" and 1/2" breakers. (30 trip points)

for the record, my breaker panel is about 40 yrs old and it has only 8 slots. I have a gas stove, dryer, hw heater and boiler so I wont need any big appliance circuits but the 8 slots I have is too small for this old NYC colonial house. ConEd is delivering 100 amp service to the house and its been fine thus far but a few more circuits with the panel described above would make a big difference with the updates I am doing. Con Ed says I can have the panel replaced only by an electrician but I can use any panel I want so long as the service breaker is not more than 100 amps. I also found out that most of the wiring can be done by me since this is a private house, so long as all work conforms to NEC and the supplemental NYC code mods, which is 99% the same for single family houses.

Re: Breaker Panel Question

Sounds like your whole house is gas and most of your loads are either lighting or air conditioning.

How many free spaces do you have?
Is your SE panel in good shape?
How many square feet is your house and the planned addition?
What are your other electrical loads?

Maurice Turgeon, thesemi-retiredelectrician.com

Re: Breaker Panel Question

I have 8 total and 1 space free.
The panel seems to be ok as is, no dents, punctures or rust. Just a little small.

Im not adding to the house I am just renovating. House is total 1577 sq ft with basement, 2 floors and attic.
With that, I have the kitchen, a 1/2 bath and dining room all on one ckt and a full bath shares the same ckt as 2 bedrooms. So you see my small dilemma :)
After that, I am going to finish a walk up attic and wire that for a few outlets and some ceiling lights. It has none now. Attic will remain as storage only and a place for my 9 yr old to play with his Lionel Trains. (I just want to finish it up a little and add drywall + insulate) So Im not adding to the house, just bringing it up to 2011. I am updating the kitchen and baths so I am going to wire them all correctly as long as Im at it.

As far as loads go, I have lighting, 3 small window AC's, fridge, dish washer, washer unit (all new stuff) and a fair amount of computer equipment that will have an iso ground ckt. Thats about it.

Re: Breaker Panel Question

(3) window units 12A
lighting 10A
fridge 3A
DW 13A (drying)
clothes washer 3A
computers 3A
trains 1A
45A (max @120v)

Sounds like you're a prime candidate for a 125A 120/240v 24 space MLO panel. Move at least one of the circuits from the existing panel to the new panel, then feed the new panel with #2 copper from a 100A 2 pole breaker.

You're only using 45A but have 100A available and even if you
add another 35A you will only be at 80% of the continuous
load, of the new breaker.

I would suggest adding two separate 20A circuits to the
counter tops in the kitchen and another 20A to the bath room.
These should be on GFCI protection.

All the other new circuits should be on AFCI breakers.

All new receptacles should be tamper resistant.

This will bring you lots closer to the 2011 Code.

If you have any questions, just ask. Good Luck

Maurice Turgeon, thsemiretiredelectrician.com

Re: Breaker Panel Question

I was thinking to just replace the old panel with the new one and migrate the circuits off the old panel. Then renovate one room at a time, adding new compliant circuits as needed and retire the old circuits one at a time.

Re: Breaker Panel Question

Replacing the old panel would be a little more money and require pulling the meter and possibly being without ***** overnight. But you would have a much better job when done. I would upgrade to 200A for the very small adder.

Also, you would probably need to replace the service drop, meter box and ground rods.

Some jurisdictions will allow the home owner to DIY, after passing a short test.

Maurice Turgeon, thesemi-retiredelectrician.com

Re: Breaker Panel Question

Thanks Maurice. Its nice to get advice from someone who knows what they are doing.
So I spoke to a rep at Con Ed and I cant get my drop upgraded because my drop is shared by me and my neighbors house although we have our own meters. (this is typical of Brooklyn and Queens with row houses) In any case, the rep from Con Ed said my service is good for 150 amps between the 2 houses but my panel can not exceed 100 amp with the drop as it is now. Which I am ok with since my load here is not so high anyway. All I need to do now is get a qualified electrician to swap it out and for how much I do not know. Seems the panel itself is not so bad at about $100 from the home depot and includes 8 breakers.

Re: Breaker Panel Question

Your welcome, dephcon5, glad to help.

Maurice Turgeon, thesemiretiredelectrician.com

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