Garfish ( and others using similar set-up's ): Even if you have four 20 amp breakers, you do realize that these are being fed by a single 30 amp breaker. As such, you are limiting the total current capacity of the sub-box to 30 amps total, regardless of how many breakers and their ratings in the secondary box.
From my line of thinking, you should have had the electrician tie the secondary breaker box into the mains. This would bypass the 30 amp breaker and allow you to pull as much as you needed from the mains. The only limitation at that point would be the master breaker on the smaller secondary box. In order to do this though, you would need to replace the 10 gauge wiring that goes from the AC mains to the secondary box with something heavier.
In my opinion, 8 gauge is sufficient to handle 30 amps continuously, so you would need at least 4 gauge for an 80 or possibly 100 amp service. That is, if you were ever going to pull that much power on a steady-state basis. The reason that they can get away with using smaller gauged wires in most installations is due to the fact that most people aren't pulling that hard on all of the circuits at the same time, so momentary overloads are not that big of a deal.
Please bare in mind that i am NOT a certified electrician and building / electrical code may vary from location to location. As such, the info that i or anyone else posts to a thread like this should always be verified at the local level prior to taking it for "gospel" and acting upon it.
As i've mentioned before, PLEASE correct me if i suggest something wrong, as this is NOT just a matter of opinion on stuff like this. It can be a matter of life, death and /or personal property loss. None of these are matters where mistakes should be allowed to slide as far as i'm concerned and those that are knowledgable and / or skilled professionals should chime in ASAP in such cases. I would much rather have a boot to the head than be responsible for possibly helping someone to kill themselves or harm their gear. If you don't know what you are doing with electricity and wiring, DON'T try this stuff on your own. Sean
>
PS... Unlike 9 volt batteries, you should never put AC wiring into your mouth and touch it to your tongue to see if it is live : )
From my line of thinking, you should have had the electrician tie the secondary breaker box into the mains. This would bypass the 30 amp breaker and allow you to pull as much as you needed from the mains. The only limitation at that point would be the master breaker on the smaller secondary box. In order to do this though, you would need to replace the 10 gauge wiring that goes from the AC mains to the secondary box with something heavier.
In my opinion, 8 gauge is sufficient to handle 30 amps continuously, so you would need at least 4 gauge for an 80 or possibly 100 amp service. That is, if you were ever going to pull that much power on a steady-state basis. The reason that they can get away with using smaller gauged wires in most installations is due to the fact that most people aren't pulling that hard on all of the circuits at the same time, so momentary overloads are not that big of a deal.
Please bare in mind that i am NOT a certified electrician and building / electrical code may vary from location to location. As such, the info that i or anyone else posts to a thread like this should always be verified at the local level prior to taking it for "gospel" and acting upon it.
As i've mentioned before, PLEASE correct me if i suggest something wrong, as this is NOT just a matter of opinion on stuff like this. It can be a matter of life, death and /or personal property loss. None of these are matters where mistakes should be allowed to slide as far as i'm concerned and those that are knowledgable and / or skilled professionals should chime in ASAP in such cases. I would much rather have a boot to the head than be responsible for possibly helping someone to kill themselves or harm their gear. If you don't know what you are doing with electricity and wiring, DON'T try this stuff on your own. Sean
>
PS... Unlike 9 volt batteries, you should never put AC wiring into your mouth and touch it to your tongue to see if it is live : )