I see this has been asked several times already. So one more time won't hurt.

Here is the scenario. I've added a 900 square ft. addition to the back of my attatched garage. I piped 1 1/2" conduit from the main 200 amp panel to the location of the new 100 amp sub panel. This addition is a mother in law suite complete with gas furnace and 1 1/2 ton a/c. seeing how this is in conduit am I correct in not using ser 2/2/2/4?

What are my options? Are there any pro's to using copper instead on aluminium? The existing panel has a vacant 100 amp breaker which I will use to feed the sub panel.

On a side note this is in ohio- does every breaker other than gfi protected need to be arc fault?

Thanks

You are correct, you will not want to pul SER cable through conduit.

You can use 3- #2 Al XHHW and 1 # AL XHHW pulled through the conduit.

AFCI must be used to protect all 120 volt outlets (the word "outlets" means all receptacles, lighting fixtures, and smoke detectors) located in, and I quote from the 2008 NEC:

"family rooms, dining rooms, living rooms, parlors, libraries, dens, bedrooms, sunrooms, recreation rooms, closets, hallways, or similar rooms, or areas".

GFI protection covers the remaining areas of a home, such as kitchens, bathrooms, unfinished basements, garages.

Would be good to consult with your local city or state code for changes or waivers to the national electric code.

You are correct, you will not want to pul SER cable thru conduit.

You can use 3- #2 Al XHHW and 1 # AL XHHW pulled thru the conduit.

AFCI must be used to protect all 120 volt outlets (the word "outlets" means all receptacles, lighting fixtures, and smoke detectors) located in, and I quote from the 2008 NEC:

"family rooms, dining rooms, living rooms, parlors, libraries, dens, bedrooms, sunrooms, recreation rooms, closets, hallways, or similar rooms, or areas".

GFI protection covers the remaining areas of a home, such as kitchens, bathrooms, unfinished basements, garages.

Would be good to consult with your local city or state code for changes or waivers to the national electric code.



All I ever hear about these arc fault breakers is how they are a nusiance and very exspensive.

So even dedicated outlets for fridge and microwave etc need to be arc fault?

Seeing how gfi would be cheaper, is that the wrong way of thinking?
I suppose I could change the breakers afer inspection:)

Also, I've been informed that I will need to run 3-3-3-6 copper or #1 AL

Because supposedly 2-2-2-4 AL is not sufficient, a joke in my eyes.

GFCI and Arc Fault are looking for very different conditions.

A GFCI is looking for a difference of current between the hot and neutral conductors. If the amperage has a difference of 0.6 of an amp, it cuts the circuit off. Its purpose is to protect a person from getting electrocuted.

An Arc Fault is looking for the electrical signature caused by an arc.

Its purpose is to protect against fire. Arcs can generate heat and spark.

If an Arc Fault is constantly tripping, then you need to get busy and take a long hard look at the conductors and splices served by that breaker.

So if I have an outlet dedicated to a microwave above the stove is it a gfi or an arc fault?

Likewise for a disposal and dishwasher? Fridge? Outlet for a washing machine?

No, the one exception in the kitchen is the refrigerator, does not need to be GFI or AFCI protected.

Anything safety related can be a nuisance. I personally do not have nay experience with AFCI breakers, don't do any residential work lately. I know GFI were a problem in the beginning, but they have gotten much better, that if it trips, there is a real problem, usually because of a cord or an appliance that got wet.

Suing GFI receptacles help just protect the device plugged in, and not the entire circuit.

An AFCI will see an arc or spark in a loose connection, switch, or light. These can be eliminated, but sometimes like looking for the needle in a haystack. AFCI was originally proposed to help shut off power when arcing was occurring on lamp and appliance cords, that get stuck behind furniture and dry out and the insulation cracks and falls off.

Currently, as far as I know, only breaker type AFCI devices are made. AFCI receptacles have not be marketed yet, for some reason. Getting the protection closer to the usage will help with nuisance trips.

Also,


so if i have an outlet dedicated to a microwave above the stove is it a gfi or an arc fault?

likewise for a disposal and dishwasher? fridge? outlet for a washing machine?

No, GFI not needed.

The kitchen counter and other general purpose outlets, not specific stationary appliances.

Also,



No, GFI not needed.

The kitchen counter and other general purpose outlets, not specific stationary appliances.

I understand that your stating the fridge does not need to be gfi-
But under the new code wouldn't it need to be an afci breaker?

My same question arises for the over the stove microwave and if the disposal is not hard wired that question arises also

Thanks

No the kitchen appliances do not need any special protection, including AFCI, as they are not listed in the NEC requirements I posted:

"family rooms, dining rooms, living rooms, parlors, libraries, dens, bedrooms, sunrooms, recreation rooms, closets, hallways, or similar rooms, or areas".

Not to beat a dead horse but how about the outlet for a washing machine in the laundry rm? And the light fixture in the laundry rm?

The washer does not need AFCI at all or GFI protection, generally.

If the washer is in an unfinished basement, or within 6 feet of a sink, it will need GFI protection.

The light does not need AFCI protection. It can be on a local lighting circuit that happens to be AFCI protected.