I am looking to add a subpanel to my house outside and next to the main panel. The main panel is 150 amp and I was told that I can run a 100 amp breaker from my main into a 125 amp subpanel. I was told to take out the AC breaker from my main and put the 100 amp breaker into the slot and the run the 2\0 wire from the breaker into the sub. Then I would take the AC breaker and put it into the sub and then fill in the rest with the new wiring from the basement. I am running three different circuits in the basement and then one out to the garage. Does any of this sound right? Thanks from Colorado

Pretty much right, except for the 2/0 part. WHO told you to run 2/0 to a 100A sub-panel.

Around here we use #2AL or #4CU. Some places would require #3CU or #1AL for 100A.

Are you aware of all the codes involved with doing this job?

In the previous question, I was asking if the way to wire up a sub panel was correct. I was questioned by the reply as to why I was running a 2/0 wire feed from the main to the sub. I was wrong in the size and type of wire. I have (UL) 600 volts AWG 4 Cu type MTW for the main wires and the ground is a AWG 6 CU. I hope that is better rated than the 2/0 wire I had said earlier. I was told by a hardware store employee that that is what he recommended but when I got home I went to another store and this is what I actually have. It is for a feed from the main 150 amps to a sub of 100 amps. The sub is rated for 125 but I don't see the need for the extra, unless it would be better in the long run . How much of a drain will it put on the system with this new sub panel?

WHy not just keep this information with the other existing thread? It gets very confusing this way.


Only you will know what the drain on the system will be. It will only be what you draw.