Look at all the clams you'll find.

And maybe the inspector will get crabs.

 

I can only hope.

 

My understading is you can have to buy a kit to convert a "main breaker" panel to a sub-panel. The kit address the isolated neutral bar and you remove a jumper.

You can have a 200 A breaker in the sub, but the panel would be fused at the main panel say at 60 A.

You do have to separate ground and neutral all the way back to the main panel.

Out buildings require a ground rod primarily for lightning. They don't get the ground/neutral bond.

The number of circuits and/or convenience determine whether you want a "main breaker" in the sub-panel.

 

Panels without a main breaker is called a "straight buss" panel. A panel called a"split buss" panel is a panel that takes 6 double pole breakers (breakers must be 30 amp or larger), on the top of the panel, of which One of those breakers feed the lower part of the panel which operates 20 amp or less amp branch circuits which are either 240 volts or 120 volts. The rule is basically this, You may have up to 6 movements of your hand to turn off all the electricity without having a Main breaker. ( which takes only 1 motion of the hand). The panel described above usually cost less than a panel that has a main circuit breaker. If you feed a sub panel with # 6 wire, then a 60 amp breaker is needed in the service entrance main panel. A 60 amp breaker is not needed in the sub panel. Only branch circuit breakers are needed. When 2 same size breakers protect something like a sub panel, motor, air-conditioner, the furthest breaker away usually trips before the closest breaker for some reason. The closest breaker is usually, more used ,as a disconnect for service, so the service man can visually see the breaker is off and that no one could turn it on without him knowing it. Thats just one advantage. That would be the reason a sub panel would have a main breaker unless someone didn't know any better. The sub panel main breaker has to be the same amperage or less than the breaker at the power source, not larger. If you make it less an advantage of this would be that the smaller breaker size will now trip first if there is a problem, like a short circuit or overload.

 

I The sub panel main breaker has to be the same amperage or less than the breaker at the power source, not larger. If you make it less an advantage of this would be that the smaller breaker size will now trip first if there is a problem, like a short circuit or overload.

I'm virtually 100% certain the sub panel main breaker can be anything. The one in the main panel does the wire protection anyway. A higher amperage breaker just becomes a disconnect. A lower amperage breaker "trips first". The important thing is to assure the wire is current limited by the breaker at the source end of the wire.

You need the "kit" to convert a "main breaker" to a "sub-panel". The sub-panel w/o a breaker is known as a "Main Lug". It's a sub-panel by default.

Sub-panels have separate neutral and ground buses.

You can read the NEC online. I haven't done it in a while.

The "6" rule is what I remember.

 

My understading is you can have to buy a kit to convert a "main breaker" panel to a sub-panel. The kit address the isolated neutral bar and you remove a jumper.

You can have a 200 A breaker in the sub, but the panel would be fused at the main panel say at 60 A. This is incorrect. A 200 amp breaker must be feed with 200 amp wire. Now, if you installed a 200 amp staight buss panel, (no main) then you might be able to get away with that. A 60amp sub panel should not have the ability to have 32 or 40 circuits. I think a 12 circuit panel for 60 amp would be best. I have never seen what you described, not that it hasn't been tried. Whatashame out

You do have to separate ground and neutral all the way back to the main panel.

Out buildings require a ground rod primarily for lightning. They don't get the ground/neutral bond.

The number of circuits and/or convenience determine whether you want a "main breaker" in the sub-panel.

 

Just to add this. A 100 amp panel is not allowed to have more than 24( branch circuits) circuit breakers. The max circuits allowed for 200 amp panel is 42 circuits. Everybody usually breaks this rule. The NEC is guide lines for new construction, not old work, but try telling an inspector that. It's in black n white in the code book.

 

I'm virtually 100% certain the sub panel main breaker can be anything. The one in the main panel does the wire protection anyway. A higher amperage breaker just becomes a disconnect. A lower amperage breaker "trips first". The important thing is to assure the wire is current limited by the breaker at the source end of the wire.

You need the "kit" to convert a "main breaker" to a "sub-panel". The sub-panel w/o a breaker is known as a "Main Lug". It's a sub-panel by default.

Sub-panels have separate neutral and ground buses.

You can read the NEC online. I haven't done it in a while.

The "6" rule is what I remember.

No they can't. A main breaker must be fed with same amp wire as breaker indicates. Just lugs, and no breaker, maybe so.