Electric

patrickkawi37

Well-Known Member
I have a 100 amp breaker on the main panel for my subpanel and 150 amp main breaker. I know I am getting close. Both the breakers are warm . I havent popped anything yet. How close is too close? I can put my Hand on them for more than 10 seconds. I just had an electrician come and rewire the subpanel with bigger wire. Does this mean I'm good to go?
 

adower

Well-Known Member
I believe you dont want to push over 80% of the max load. I have the same setup and my electrician said you dont want to run more than 80amps at once.

What size wire? I have 2 gauge going to mine.
 

patrickkawi37

Well-Known Member
I believe you dont want to push over 80% of the max load. I have the same setup and my electrician said you dont want to run more than 80amps at once.

What size wire? I have 2 gauge going to mine.
I think it's 1awg or something like that . I had 4 gauge before and it was sketchy af. I pulled it out and had the electrician redo everything . the other room is In veg right now so the lights aren't flipping one room on one room off. So I added the amps and got 140 total . Because I got 140 total I decided to go feel the breaker. She was pretty toasty . I am just worried If over time this is dangerous being borderline
 

patrickkawi37

Well-Known Member
5 dehu 38 amps
3 mini splits 40 amps
Lights 60 amps
Fans , pumps ect. At least 20 amps
Video games, TV , kitchen light , living room light, ceiling fans .
 

droopy107

Well-Known Member
If your load were equally balanced you would only be at 70 amps per leg. That being said, balance usually wont happen without conscious effort in the wiring department. Spread the load out as equally as you can in your sub panel and you're plenty fine with the 100 amp sub. 1 awg is good for 150 amps so you are covered back to the main box as far as the wire and main breaker go.

P.S. I'm assuming the feed to the sub is 240 volt.
 

patrickkawi37

Well-Known Member
If your load were equally balanced you would only be at 70 amps per leg. That being said, balance usually wont happen without conscious effort in the wiring department. Spread the load out as equally as you can in your sub panel and you're plenty fine with the 100 amp sub. 1 awg is good for 150 amps so you are covered back to the main box as far as the wire and main breaker go.

P.S. I'm assuming the feed to the sub is 240 volt.
The lights and acs and subpanels are on 240v
 

patrickkawi37

Well-Known Member
If your load were equally balanced you would only be at 70 amps per leg. That being said, balance usually wont happen without conscious effort in the wiring department. Spread the load out as equally as you can in your sub panel and you're plenty fine with the 100 amp sub. 1 awg is good for 150 amps so you are covered back to the main box as far as the wire and main breaker go.

P.S. I'm assuming the feed to the sub is 240 volt.
Electrician had mentioned we could use a bigger breaker than 100 if I have any problems . 125 would probably be best . But the main being warm is that bad? That means I'm getting close to max right?
 

CC Dobbs

Well-Known Member
I have a 100 amp breaker on the main panel for my subpanel and 150 amp main breaker. I know I am getting close. Both the breakers are warm . I havent popped anything yet. How close is too close? I can put my Hand on them for more than 10 seconds. I just had an electrician come and rewire the subpanel with bigger wire. Does this mean I'm good to go?
Bigger wires is better but I don't know much more about electricity except that is magic.
 

Carolina Dream'n

Well-Known Member
Your definitely pushing it man. I would have a 200 amp main installed if possible, shit a 300 if they'll do it. Upgrading the wire only does so much if the breaker itself is overloaded.
 

patrickkawi37

Well-Known Member
Is there a reason you're not asking your electrician? He is probably your best bet on solid info?
He says if you can put your finger on the breaker for more than 20'seconds your good. He's going to come out in next couple days and check. Problem is it's only running heavy at night and he's a busy dude so within the week.
 

patrickkawi37

Well-Known Member
Your definitely pushing it man. I would have a 200 amp main installed if possible, shit a 300 if they'll do it. Upgrading the wire only does so much if the breaker itself is overloaded.
I can't do an upgrade here this is as good as it gets . Shouldn't the breaker be good until it pops then you know you used too much? Electrician said that it's rated for 20% under so running at max isn't bad unless the breaker is popping. Is this correct ? I am hoping when I am not vegging it will be better. I will put a 125 amp breaker and see if that cools that one at least . The wire itself is not hot . Just the breakers are toasty
 

droopy107

Well-Known Member
Electrician had mentioned we could use a bigger breaker than 100 if I have any problems . 125 would probably be best . But the main being warm is that bad? That means I'm getting close to max right?
All electrical equipment will heat up during use. The heaver the load the greater the heat signature, but that would not be a reliable indicator of where you are at load vs. max capacity. I agree with your electrician about the touch test. That's a crude way to test, but for what it's worth to you, if you can touch it for 20 seconds it wont be starting any fires for you. How loaded is one leg vs. the other? That's useful info. have him clamp his amp meter on each leg under max load and you will know for sure where you're at. Wait until your sparky stops by. If he's competent he'll tell you the same thing I said here. Balance the load. Although There is nothing wrong with changing out the sub breaker either, it's just a little pricier, but you would gain capacity to your operation.

A 240 V breaker is just two 120V breakers designed to shutdown both if either leg reaches max amperage. On your 100 amp breaker it is theoretically possible to be unbalanced in a way that is pulling 99 amps from one leg and nothing from the other, effectively leaving 99 amps of capacity on the table, unused. That's why balance is so important to get the most out of your electrical design.
 

patrickkawi37

Well-Known Member
All electrical equipment will heat up during use. The heaver the load the greater the heat signature, but that would not be a reliable indicator of where you are at load vs. max capacity. I agree with your electrician about the touch test. That's a crude way to test, but for what it's worth to you, if you can touch it for 20 seconds it wont be starting any fires for you. How loaded is one leg vs. the other? That's useful info. have him clamp his amp meter on each leg under max load and you will know for sure where you're at. Wait until your sparky stops by. If he's competent he'll tell you the same thing I said here. Balance the load. Although There is nothing wrong with changing out the sub breaker either, it's just a little pricier, but you would gain capacity to your operation.

A 240 V breaker is just two 120V breakers designed to shutdown both if either leg reaches max amperage. On your 100 amp breaker it is theoretically possible to be unbalanced in a way that is pulling 99 amps from one leg and nothing from the other, effectively leaving 99 amps of capacity on the table, unused. That's why balance is so important to get the most out of your electrical design.
I believe the subpanel is pretty balanced. He moved a couple things from one side to the other before when we changed to bigger wire . Thanks for the info . I will have him test and see how much exactly I am pulling from each leg
 

Aeroknow

Well-Known Member
I believe the subpanel is pretty balanced. He moved a couple things from one side to the other before when we changed to bigger wire . Thanks for the info . I will have him test and see how much exactly I am pulling from each leg
Glad to see you finally upgraded the wire;-)
If i'm not mistaken, it is a very long run to that subpanel rite? Hopefully a 125amp breaker will be ok to install. That sparky should be able to tell you yes or no. If 125 is ok, I would just do it already.

Splitting up the load is easy. Everything 240v is already split up. Do a load calculation for everything @ 120v, and make sure it's split up. Easy peasy. Again, glad to hear you finally upgraded the main wires. They were very undersized before.
 

ttystikk

Well-Known Member
Smoke your sparky out and ask him/her questions. That's how I developed my own knowledge of electrical wiring- and it taught me what's safe for a DIY upgrade and when it's time to call him. In my case, he does the panels and I can take it from there.

Load balancing is important and again, only the 120V stuff is potentially unbalanced as your 240V equipment already pulls from both legs equally.

The only wires that don't heat up under an electrical load are superconductors- and I promise you don't have any of those! A warm wire at full load is not of concern, as long as you can keep your hand on it you're good. Breakers are similar. When you smell hot plastic that's when you drop everything and find out what's cooking! With any luck, your nose will lead you to the kitchen, where your girlfriend left the shrink wrap on the stove, lol
 

patrickkawi37

Well-Known Member
Glad to see you finally upgraded the wire;-)
If i'm not mistaken, it is a very long run to that subpanel rite? Hopefully a 125amp breaker will be ok to install. That sparky should be able to tell you yes or no. If 125 is ok, I would just do it already.

Splitting up the load is easy. Everything 240v is already split up. Do a load calculation for everything @ 120v, and make sure it's split up. Easy peasy. Again, glad to hear you finally upgraded the main wires. They were very undersized before.
It's around 100 feet of a run . I believe 125 is what the wire is rated for at this distance. I will have him add the 125amp breaker. I been adding dehus and pumps here and there so I slowly have been maxing it out. I didn't know that it's normal for breakers to be warm that makes me feel a lot better .
Smoke your sparky out and ask him/her questions. That's how I developed my own knowledge of electrical wiring- and it taught me what's safe for a DIY upgrade and when it's time to call him. In my case, he does the panels and I can take it from there.

Load balancing is important and again, only the 120V stuff is potentially unbalanced as your 240V equipment already pulls from both legs equally.

The only wires that don't heat up under an electrical load are superconductors- and I promise you don't have any of those! A warm wire at full load is not of concern, as long as you can keep your hand on it you're good. Breakers are similar. When you smell hot plastic that's when you drop everything and find out what's cooking! With any luck, your nose will lead you to the kitchen, where your girlfriend left the shrink wrap on the stove, lol
Good advise . I am helping the electrician in his grow so I'm going to pick his brain and try to learn more of this electrical stuff.
Thanks for the help guys I'll let you know what I find out.
 
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