Locating the MCC

DANGER
Hazard of Electric Shock, Explosion, or Arc Flash Apply appropriate personal protective equipment (PPE) and follow safe electrical work practices. See NFPA 70E, NOM-029-STPS, CSA Z462, or local equivalent. This equipment must only be installed and serviced by qualified electrical personnel. Turn off all power supplying this equipment before working on or inside equipment. Always use a properly rated voltage sensing device to confirm power is off. Replace all devices, doors, and covers before turning on power to this equipment. When moving MCC sections, follow the instructions in Handling the MCC. The MCC has a high center of gravity, which may cause it to tilt. Failure to follow these instructions will result in death or serious injury.

DANGER

Hazard of Electric Shock, Explosion, or Arc Flash

Apply appropriate personal protective equipment (PPE) and follow safe electrical work practices. See NFPA 70E, NOM-029-STPS, CSA Z462, or local equivalent.
This equipment must only be installed and serviced by qualified electrical personnel.
Turn off all power supplying this equipment before working on or inside equipment.
Always use a properly rated voltage sensing device to confirm power is off.
Replace all devices, doors, and covers before turning on power to this equipment.
When moving MCC sections, follow the instructions in Handling the MCC. The MCC has a high center of gravity, which may cause it to tilt.

Failure to follow these instructions will result in death or serious injury.

MCCs are designed for use in non-hazardous locations. Choose a location for installation that is well ventilated and free from excess humidity, dust, and dirt. The temperature of the area must be no less than 0°C (32°F) and no greater than 40°C (104°F). Protect the MCC from the entrance of water or any moisture. If necessary, protect the MCC from condensation by ordering internal space heaters.

Space Requirements

Install MCCs in an area with a minimum of 3 ft. (0.9 m) of free space in front of front-of-board construction. An additional 3 ft. (0.9 m) is necessary in the rear of back-to-back construction. This free space provides adequate room to remove and install units. (More space may be required for some applications; refer to applicable local and national installation codes.) Provide at least 0.5 in. (13 mm) of space between the back of front-of-board MCCs and a wall. For damp locations, provide at least 6 in. (152 mm).

When selecting a location for the installation of an MCC, carefully consider accessibility, overhead clearances, and future expansions. Considering these factors minimizes many difficulties during this and future MCC installations.

NOTE: Model 6 MCCs with the arc-rated option have pressure-relief roof flaps for top venting of arc fault gases. These MCCs require a minimum of 28.5 in. (724 mm) from the top plate of the MCC to the nearest obstruction (minimum ceiling height of 10 ft. (3 m) including base channel). See Required Obstruction-Free Area concerning the required clearance above the equipment.

DANGER
Burn hazard from HOT GASES Apply appropriate personal protective equipment (PPE) and follow safe electrical work practices. See NFPA 70E, NOM-029-STPS, CSA Z462, or local equivalent. Keep the area directly above the equipment clear and unobstructed for 28.5 in. (724 mm) from the roof. Failure to follow these instructions will result in death or serious injury.

The shaded area (see Required Obstruction-Free Area) above the arc-rated MCC must be free from obstructions.

Required Obstruction-Free Area

Aligning the MCC

Provide a smooth, level surface for installation. An uneven foundation may cause misalignment of shipping blocks, units, and doors. The surface under an MCC must be of a non-combustible material unless bottom plates are installed in each vertical section.