80459-641-01, Rev. 09

Modifying Removable Units

  1. Turn off all power supplying this equipment before working on or inside the equipment, and follow lockout/tagout procedures. Always use a properly rated voltage sensing device to confirm the power is off.

  2. Remove the MCC unit from the structure. See the procedure for Maintaining the Control Unit of this manual.

  3. Perform the required modifications. Use thread-forming screws to mount devices. Do not use bolts and nuts, as they could loosen over time and cause property damage or personal injury. The hardware must not extend beyond the back of the MCC unit saddle more than 0.25 in. (6 mm) or beyond the sides and bottom pan by more than 0.125 in. (3 mm).

  4. Maintain proper electrical spacings

    • Through air between live parts (301–600 volts)—In motor control units: 0.375 in. (9.5 mm); in other MCC units: 1.0 in. (25.4 mm).

    • Over (insulation) surface between live parts (301–600 volts)—In motor control units: 0.5 in., (12.7 mm); in other MCC units: 2.0 inches (50.8 mm).

    • Between live parts and grounded metal (0–600 volts)—in motor control units: 0.5 in. (12.7 mm); in other MCC units: 1.0 in. (25.4 mm).

    Spacing values above can also be used at lower voltages. For conditions other than those noted, contact Schneider Electric. * in the unit.

  5. Use a vacuum cleaner to remove all debris left in the unit as a result of the modifications. Do not use compressed air to blow out the unit, because all debris may not be fully removed.

  6. Perform the recommended maintenance procedures beginning in Maintaining the Control Unit of this manual.

  7. Ensure that vertical bus closing plugs are in place (with the exception of one plug where the MCC unit will stab on the vertical bus). If other vertical bus closing plugs are not in the proper position, ensure that all power is removed from the vertical bus and reinstall the vertical bus closing plugs.

  8. Use a megohmmeter to perform an insulation test as outlined in Insulation Test.

  9. Look for and clear any obstructions that would not permit proper energizing of the MCC unit.

  10. Reinstall the MCC unit and follow the procedures for Energizing the MCC of this manual.

QR Code is a registered trademark of DENSO WAVE INCORPORATED in Japan and other countries.

Was this helpful?