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Discussion Starter · #1 ·
I posted on this issue before but didn't realize the my current subpanel is only 120V. Here is a quick summary of what I'm doing:

I am moving a wall that currently contains an old subpanel. I will put in a new subpanel on the new wall and will run a new feed wire from the main as well as new wires to the first junction boxes downstream (that's a term we use in the water industry, not sure if it translates to electrical industry) of the subpanel.

I've researched subpanel topics on this website and it seems that all of them are 240 volts. My problem is that my current subpanel is only 120 volts and it is fed from a 30 amp breaker in my main. Attached is a picture of my main and the wiring diagram. Is there a way for me to rearrange my breakers so that I can get 240 to my subpanel? If not, does it really matter if my subpanel is only 120? I'm not changing or adding any load - I'm just upgrading the panel and some wires.

Also, I showed what I've changed since taking the picture. I connected two of the breakers together (they weren't when the picture was taken), and I changed the two 50-amp breakers to two 30-amp breakers for my dryer. Not sure why they were 50-amp before.

Thanks!




And here is the old subpanel that I am replacing

 

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The first thing you need to convert a 120 volt subpanel to 120/240 volts is another hot wire. Practically you need to run a new cable with 3 conductors plus ground.

On a typical panel, a double wide breaker will give you 120/240 volts but not all possible positionings in the panel will work for all brands of panels. You can move a single breaker up or down to get a pair of slots that give 240 volts for the double wide breaker. In your case you might move the lower left breaker to the top left and put the subpanel breaker set at the lower left. Measure the voltage between the two fins in the adjacent vacant slots to be sure you get 240 volts.
 

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Discussion Starter · #4 · (Edited)
Thanks for the tips - it seems easy enough! :)

By the way, on the wiring diagram, what do the different number of lines mean? For example, 1 2 3 and 4 come off of one line but 5 and 7 are two lines that branch off of one. Do those lines indicate where I can have two pole breakers or do they show where I can have mini breakers?
 

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A "Handy Husband"
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Thanks for the tips - it seems easy enough! :)

By the way, on the wiring diagram, what do the different number of lines mean? For example, 1 2 3 and 4 come off of one line but 5 and 7 are two lines that branch off of one. Do those lines indicate where I can have two pole breakers or do they show where I can have mini breakers?
Diagram shows where you can use the slim (mini) breakers; 1-4 are full size only, the rest are full or slim.

You panel is a mess, take the time to clean it up. Splice the wires out to make them longer so the wires stay out at the edges of the panel and not run across the face. Don't make the wires too long so that you have to deal with a bunch of slack.That cable sheath should not be in the box, strip it back to the NM cable connector.
 

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Discussion Starter · #8 ·
Diagram shows where you can use the slim (mini) breakers; 1-4 are full size only, the rest are full or slim.

You panel is a mess, take the time to clean it up. Splice the wires out to make them longer so the wires stay out at the edges of the panel and not run across the face. Don't make the wires too long so that you have to deal with a bunch of slack.That cable sheath should not be in the box, strip it back to the NM cable connector.
I think you are right - a good cleaning is definitely needed!
 

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Discussion Starter · #9 ·
So, here's the plan:

- Move all the breakers on the left side of the main down one slot to make room for a two pole breaker.
- Install 60 amp two pole breaker at main.There isn't a need to upgrade but I figured I might as well since I'm running new feeder wire.
- Run new 6/3 copper to new subpanel
- Install new flush mount subpanel inside
- Make sure that ground and neutral in subpanel are separated
- Install new breakers (AFCI as needed) in subpanel
- Run new wires to first junction boxes off of subpanel
- stand on a wood chair, say three hail mary's, close my eyes, and flip the breaker. :laughing:

Anything else?
 

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A "Handy Husband"
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So, here's the plan:


- stand on a wood chair, say three hail mary's, close my eyes, and flip the breaker. :laughing:
Do it right and take your time and this will not be necessary. Before I activate a new circuit, I take the time to use a multimeter (ohmmeter) and make sure there are no grounds or shorts any place not called for. No continuity between the hot conductors or from the hot conductors to ground and neutral.
 
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