MOTOR600V>200-A Motors, 3-Ph, 600 Volts or 200 Hp and Above - Annual

                                                      Man Hours 6
Special Instructions:

1.  Schedule shutdown with operating personnel as necessary.
2.  Coordinate this maintenance with the motor controller and
    the driven equipment.
3.  Some units require removal of access screens or plates.
4.  Review manufacturer's instructions.
5.  De-energize, tag, and lock out power circuits.
6.  Ground electrical circuits in the unit prior to cleaning or servicing to
    discharge any capacitors.
7.  Record and report deficiencies.
8.  Cleaning:  Without disturbing adjacent areas or redistributing dirt, dust,
    and contaminants, use a small vacuum cleaner to enter into narrow openings,
    such as end bells, ventilation ports, etc.
10. Do not spray liquid solvents onto motor windings.  If solvents must be used,
    only those approved for electric motor cleaning should be used.  Wipe with
    damp but not wet rags.  Several wipings may be required for heavily soiled
11. Lubrication:  Use lubricants specified by the manufacturer only, or get
    approval from the regional office for substitutes.

Items to Check & Initial Completion:

1.  All Motors:

    a.___ Clean ventilation ports of accumulations of dirt, dust, and other
          foreign  material with vacuum cleaner (see special instruction no. 7).
    b.___ Closely examine condition of all motor covers, screens, protective
          shields, inspection plates, and motor lead connection compartments.
    c.___ Inspect for proper anchoring coupling, mounting, grounding, and ground
          connection.  Look for signs of loose or broken bolts, motor housing
          cracks, broken motor support brackets, and any evidence of abnormal
          rust or chemical action on mechanical and electrical parts.
    d.___ Inspect bearings for signs or wear and deterioration.  Where journal
          bearings are used evaluate bearing condition and clearance.
    e.___ The lubrication system of all bearings should be inspected for
          satisfactory and normal operation.  Change oil and grease.  Do not over
    f.___ Ground motor windings according to manufacturer's instructions or 30
          minutes prior to performing electrical testing, and 30 minutes after
          completion of the test.
    g.___ All protective devices should be tested in accordance with all
          applicable procedures.

2.  Synchronous and wound rotor motors:

    a.___ Clean and check condition of slip rings and indicators.
    b.___ Check condition of all brushes.  Look for chipped, cracked, broken, or
          otherwise defective brushes.  Inspect brush pigtails for damage
          resulting from wear and environmental effects.
    c.___ Inspect all brushes for satisfactory operation and correct length.
    d.___ Check brush box, look for signs of brushes binding due to carbon dust.
    e.___ Measure the brush contact pressure of all brushes.  Using
          manufacturer's instructions, verify the amount of brush pressure to be
          applied per square inch.
    f.___ Clean and visually inspect resistor bank associated with motor.

3.  Shaft Driven Exciters:

    a.___ Measure distance from brush box to commutator on all brush boxes.
          Refer to manufacturer's specifications for the correct clearance.
    b.___ Check spacing between each brush box for equal spacing around
    c.___ Inspect commutator surface for indication of sparking, threading, drag
          grooving, feathering, etc.
    d.___ Inspect commutator for chips from broken brushes which may get stuck
          between commutator segments.
    e.___ Check mida insulation between segments.
    f.___ Resurface commutator if necessary, by hand stoning, sandpapering, etc.
    g.___ Check the runout of the commutator at several points to verify the
          accuracy of the commutator surface.  Look for high bars and out of
          round conditions.

4.  Non Shaft Driven Exciters:

    a.___ Remove access covers and vacuum the unit.
    b.___ Tighten all connections and look for signs of overheating.

5.  Electrical Tests (All Motors):

    a.___ Perform dielectric absorption or polarization test on all windings
          including exciter windings.
    b.___ Conduct dielectric absorption test for a ten minute duration.
          Sixty/thirty ration test shall be for a one minute duration.
          Polarization test shall be for a ten minute duration. Record test
          results.  Evaluate test results on motor condition.  NOTE:  On
          synchronous motor with solid state excitation, disconnect exciter
          circuits for motor before performing tests.

Tools and Materials:

1.  Standard Tool Kit
    Plus  Insulated pliers and screwdrivers
          Wire strippers
          Wire crimpers
          Voltmeter - Ohmmeter - Milliammeter
          Clamp on meter(volt - ohm - amp meter)
          Soldering kit
          1/8" 25' fish tape
          Burnishing tool
2.  Megger
3.  Vacuum cleaner with attachments
4.  Grease gun and fittings
5.  Oil can and funnel
6.  Cleaning material, rags, sandpiper, small brush, etc.  Consult the Material
    Safety Data Sheets (MSDS) for hazardous ingredients and proper personal
    protective equipment (PPE).

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