DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (http://www.diychatroom.com/)
-   Electrical (http://www.diychatroom.com/f18/)
-   -   Adding a subpanel (lots of questions) (http://www.diychatroom.com/f18/adding-subpanel-lots-questions-38390/)

epeterson777 02-15-2009 12:12 PM

Adding a subpanel (lots of questions)
 
I am finishing my basement and want to add a sub panel. I have 150a service to the main panel and calculated that my service can easily handle the new load. I figured out that I need a 40a feeder breaker for the sub panel. My problem is that my main panel only has one open slot (the bottom right) on the main panel. I don't really want to get a whole new panel because I don't feel comfortable doing it and I don't want to pay an electrician if I don't have to. So, do they make slim 15a AFCI breakers, if they do I would think the easiest fix would be to take the 2 15a AFCI breakers on the bottom right and put them together in one slot and that would give me the needed 2 slots for the new 40a feeder breaker. I also see on the left side that there are two breakers taking up two slots. If the AFCI breaker fix doesn't work do they make a 20/15 double breaker so they could go together in one slot. Then I could move a few other breakers around to make the room, which would equate to a lot of moving around. Does the 40a breaker have to be double pole since I am not going to run any 220v circuits off the new sub panel? A single pole 40 would work without having to change anything. Any other suggestions? http://i126.photobucket.com/albums/p...77/elec003.jpg
My second question is since my main panel is outside of my garage (I sure wish they would have put it in the garage or basement - is this set up common, it's the first time I have seen it). The existing wires all come in from under ground, then into the bottom of the box. I was going to run my new wire from my basement through the garage (in conduit). When I get it to the box should I just poke it through the siding and come up into the bottom of the box, or is there a better way? If I do go through the siding like that, how should I make it clean and keep everything protected? I would think just slathering caulk all over would be a pretty crappy way of going about it. http://i126.photobucket.com/albums/p...77/elec004.jpg

Magnettica 02-15-2009 12:20 PM

You could get a quad circuit breaker for both of those double pole breakers and this way you'd have room for the new sub panel circuit breaker which in my opinion should be a double pole circuit breaker using a 8/3 with a ground. I know you don't want to but you might be best suited to hire an electrician for this job because the panel is already loaded. Plus installing that quad breaker can be tricky for the homeowner.

ctsmiths 02-15-2009 01:49 PM

Is there anything that ,once you put in the sub panel, you could move from the main panel to the sub, to make room in the main panel?

epeterson777 02-15-2009 02:12 PM

I could maybe move the circuit for the smoke detectors which would give me half a slot, which would open up enough room for the new breaker. I would still have to move a lot of breakers to make this work, but it's a possibility.

The circuit I could move is for the the smoke detectors. What would I do with the existing wire coming into the main panel. I know I could connect the ground and the neutral to the bus's but what about the black wire?

Off the top of anyone's head what do you guys think an electrician would charge to remedy something like this (if I ran the 8/3 wire to the box)?

Bob Mariani 02-15-2009 02:17 PM

Yes they make mini 15/20 combination breakers.

From the garage to the outside panel. Turn off main breaker first. Use a generator for your drill. Drill a hole at the bottom right side of the panel into the garage. Use a nipple into a LB to the conduit going to your sub panel.

It appears you already exceeded the number of allowed mini breakers... but check the label to be sure. As posted it may be a good idea to move some circuits to the new panel

No slim AFCI

Sub panel needs to have a minimum of 2P60 breaker. (code)

ctsmiths 02-15-2009 02:25 PM

Quote:

Originally Posted by epeterson777 (Post 230740)
I could maybe move the circuit for the smoke detectors which would give me half a slot, which would open up enough room for the new breaker. I would still have to move a lot of breakers to make this work, but it's a possibility.

The circuit I could move is for the the smoke detectors. What would I do with the existing wire coming into the main panel. I know I could connect the ground and the neutral to the bus's but what about the black wire?

Off the top of anyone's head what do you guys think an electrician would charge to remedy something like this (if I ran the 8/3 wire to the box)?

Is there anything like a hot water heater or furnace that is in the basement that you could rewire into the new sub-panel? Its hard to say as far as a price goes without seeing the job. Some guys won't do work on circuts that homeowners have worked on, they will rewire the stuff you already did and build that into the price, unless you know the electrician.

epeterson777 02-15-2009 02:42 PM

Actually the hot water heater and the furnace are both down in the basement. The hot water heater is gas though. I just looked at the furnace and the wire passes right by the new sub box, so that would be a very easy fix, but that is on a 20a that is only taking up half a slot. Which would open up the space but I would need to move around a lot of breakers still. If I went that way, what would be the standard practice for the old incoming furnace wire (that would no longer be live) that goes into the main panel, just coil it up and leave it unattached?

Bob M, I am not real familiar with breakers, but I am assuming a 2P60 is a 60a. Are you sure that is a code that I would need that as a minimum? I have been using the Black and Decker Complete Guide to Home Wiring (I know books aren't always perfect), but for the sub panel install example, they tell you to calculate the load that you will be using (which I calculated at just under 40a) to determine which size feeder breaker to use. They actually only use a 30 amp for their example, which has a 27.2 amp load.

ctsmiths 02-15-2009 03:03 PM

Quote:

Originally Posted by epeterson777 (Post 230765)
Actually the hot water heater and the furnace are both down in the basement. The hot water heater is gas though. I just looked at the furnace and the wire passes right by the new sub box, so that would be a very easy fix, but that is on a 20a that is only taking up half a slot. Which would open up the space but I would need to move around a lot of breakers still. If I went that way, what would be the standard practice for the old incoming furnace wire (that would no longer be live) that goes into the main panel, just coil it up and leave it unattached?

The code now states that you need to remove all old unused wireing unless it is in conduit and marked as such. If it goes into the wall you dont need to take the wall down but get rid of as much as you can, also in the main panel and any boxes that are accessible.

ctsmiths 02-15-2009 03:05 PM

What are those other doubles feeding?

epeterson777 02-15-2009 03:39 PM

The double on the top right is the dryer, the double on the middle right is the oven, and the double on the bottom right is for the air conditioner.

I also just noticed there is a breaker just for my sump pump that could also be put on the sub box I would think.

I am going to start flipping breakers and see what they power and make sure they are all labeled right. Then I'll shut off the whole panel and take a look at the wiring. If the wiring is clean and done professionally I think I can tackle moving the breakers around and making some space.

ctsmiths 02-15-2009 03:45 PM

Sounds like your on the right track now.:thumbsup:

epeterson777 02-15-2009 04:46 PM

I found out the that all the wiring does come in through the wall behind it, which is good.

Alright, so here is what I am thinking I'll do...
1. Moving the kitchen lights breaker to the open slot.
2. Move the sump pump to the sub box, and remove sump pump wiring from the main panel as best I can.
3. The move the kitchen plugs breaker (which was doubled with the sump pump) together with the kitchen lights in the open slot.
4. Move the breaker that is between those open slots down to above the A/C double breaker.
http://i126.photobucket.com/albums/p...inpanel005.jpg
-That will leave me with two open slots together on the left side. After calculating the new load I came to 51.52 amps, so I would go up to a 60 amp feeder breaker instead of the original 40 (which would satisfy the code that Bob is talking about). So I would use a 6/3 cable going from the main box to the sub box.

Does that all sound legit?

If so, before I get this inspected should I move the breakers, then put the new breaker in (leave it switched off), run the wire from the sub to the main (but not connect anything). And then just pop the cover off for the inspector? If he gives it the thumbs up, then I can connect it. Is that correct?

wirenut1110 02-15-2009 05:44 PM

Do you know what code cycle (05 or 08) your area is on. This will make a difference as to the wire size you can use.

theatretch85 02-15-2009 05:55 PM

Quote:

Originally Posted by Bob Mariani (Post 230745)
Sub panel needs to have a minimum of 2P60 breaker. (code)

Actually as far as I know, the 60 amp disconnect requirement is only for detached structures. If the subpanel resides in the same house as the main panel then there is no need for a disconnect at the sub panel. However, I would recommend a disconnect of some kinda at the sub panel if it is not located next to the main panel. A 100 amp mains panel would work just fine, the 100 amp main breaker would serve only as a disconnect and the breaker in the main panel would be your OCPD (Over Current Protection Device).

Bob Mariani 02-15-2009 06:25 PM

The sub panel will still need a disconnecting means. NEC 230.79(D) All Others (more than two circuits in a dwelling) The service disconnecting means shall have a rating not less than 60 amps. But as a practical matter it would not make any sense to run something smaller. Especially since most agree to move several circuits to the new panel. And future needs are to be considered by code and practice also.
For inspection all connections should be done. Panel covers better be on. You remove them when he is there and asks you to. Safety. Never leave a panel cover off if its hot. Be sure to separate the grounds and commons (ungrounded conductor) on the sub panel. And if you move the wires to a range or dryer that is electric these too need new plugs (4 wire not 3 wire)


All times are GMT -5. The time now is 12:22 PM.


Copyright 2003-2014 Escalate Media LP. All Rights Reserved