1-7.5 Hp Man Hours .5
7.5-50 Hp Man Hours 1
50+ HP Man Hours 1.25
Special Instructions:
1. If necessary, schedule shut-down with operating personnel.
2. Review manufacturer's instructions.
3. Deenergize, tag, and lock circuit serving motor, when applicable.
Preventive Maintenance:
Items to Check & Initial Completion:
1. ___ Check ventilation ports for soil accumulation, clean if necessary.
2. ___ Clean exterior of motor surfaces of soil accumulation.
3. Lubricate bearings according to horsepower ratings:
a.___ Remove filler and drain plugs (use zerk fittings in place of filler
plug if not installed).
b.___ Free drain hole of any hard grease (use piece of wire if necessary).
c.___ Add grease - use good grade lithium base grease unless otherwise noted.
4. ___ Check motor windings for accumulation of soil. Blow out with air if
required, air pressure must not exceed 30 psig.
5. ___ Check hold down bolts and grounding straps for tightness.
Predictive Maintenance:
The following electrical tests are to be done on motors rated at 10 horsepower
and greater, and is to be accomplished at the motor control panel and should be
completely non-destructive.
Items to Check & Initial Completion:
1.___ The electrical circuits and the motors shall be non-destructively tested
from the load side of either 1) the fused side of the disconnect or 2) the
secondary side of the breaker.
Testing shall be done to establish the present operating parameters of the wiring
and the motors for the following aspects a through h.
a.___ Resistance imbalance (hot spots) with results expected to be less than
0.05 ohms in each phase;
Note: A wheatstone bridge tester will give these results.
b.___ Total inductance imbalance with results expected to be less than 35%
from a phase to phase analysis on the system. Note: A surge tester
will give these results.
c.___ Leaks to ground with results expected to be greater than 5 meg ohms in
each phase;
Note: A megger may be used to give this result.
d.___ Report on any visual findings of significance or conditions found from
testing that need further investigating.
e.___ Three phase dynamic testing of AC motors in operation will be done on
all systems operating at 600 volts or less. Record each phase voltage
balance with results expected to be less than 1% imbalance;
Results: Phase 1 _______ Phase 2 _______ Phase 3 ______
Note: Volt meters will give these results.
f.___ Capacitance imbalance when capacitors are part of the installation with
results expected to be less than 10% imbalance.
Note: "Capacitance Measurement Bridge" will give these results.
g.___ Record amps at full load or at maximum design load to be on system with
results expected to be less than nameplate full load amps.
Results Full Load:___________________
Note: An ammeter will give this result.
h.___ Record the power factor of the system under load, using a power factor
meter. Results: ________________
2.___ Compare the results of each test performed in step #1 with the previous
year's results and consider how serious the combination of problems are,
and what priority they have for repair or correction.
3.___ Restore all equipment as it was when this work was started. Remove tags
and return to service. Clean up work area.
Tools & 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. Tachometer
3. Cleaning equipment and materials. Consult the Material Safety Data Sheets
(MSDS) for hazardous ingredients and proper personal protective equipment
(PPE).
4. Lubricants. Consult the MSDS for hazardous ingredients and proper PPE.
5. Wheatstone bridge.
6. Surge tester.
7. Megger.
8. Volt meter.
9. Capacitance Measurement Bridge.
10. Amp meter.
11. Power factor meter.
Table of Contents | Next