It is my understanding and training plus field work that a disconnect must be installed in the shed to shut off all power to the building. This disconnect must be immediately inside the shed at the entrance point of the branch circuit from the house. If you are using a multi-circuit panelboard in the garage and have no more than 6 breakers in the panel, these breakers may be used as the disconnecting means. More than 6 breakers, you must have a main breaker in the panelboard.
If you are running a single 15 or 20 ampere branch circuit from the house to feed lights and outlets, you may use a separate single-pole switch (such as a standard light switch) as the required disconnect because of the location requirements of 225.32 and provided for by the 225.36 exception. This switch must be the first device that is on the circuit once it enters the shed, and it may be used only as a disconnect, it cannot be used to control lights or other equipment. You also are required to mark this as the disconnect on the box cover.
This is my understanding and experience in the field, though I do see the breaker in the house panel as the disconnect quite often I believe this is not the intent of the NEC as the required disconnect.
Last edited by Stubbie; 08-27-2007 at 04:24 PM.
Reason: changed garage to shed