Section R. 408.41727 - Switches, circuit breakers, disconnectors, transformers, and boxesRule 1727.
(1) Each switch, circuit breaker, and disconnector shall meet all of the following requirements: (a) Be marked to indicate its purpose unless it is so located that the purpose is evident and it is secured against displacement.(b) Be of the weatherproof type where damp or wet conditions exist.(2) A box for disconnecting means shall have dead fronts or covers, which shall be kept in place or closed when the panel is energized, or the requirements of R 408.41723 and R 408.41724 shall be complied with.(3) An arc shield shall be provided on a disconnect of 60 ampere capacity or larger.(4) A disconnecting means shall be provided to disconnect all energized conductors in a building or structure from the service entrance conductors.(5) An energized transformer and other related energized equipment over 150 volts to ground shall be protected to prevent accidental contact. The protection shall be an individual housing or an electrical substation fence. A metallic enclosure shall be grounded. Access to this equipment shall require a key or tool. A transformer mounted on a utility pole at a height of more than 12 feet is excepted from the requirements of this subrule.Mich. Admin. Code R. 408.41727