OHIO CAT
POWER SYSTEMS SERVICES
MCEmax Testing Overview
•MCE –
Test motors and circuits off line (with the
motor de-energized).
•Emax -
Test motors and circuits on line (with the
motor energized and in operation).
•MCEmax- Combination of the MCE and the Emax test
capabilities in one unit.
MCEmax Combination
Online & Offline Test
System
Why Test My Motors
Eliminate unexpected failures
Reduce production downtime
Understand the condition of your motors
Quality control for repairs & spares
Reduce electrical maintenance costs
Increase overall plant reliability
Predictive vs. Reactive
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Summary of Motor
Failures
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What Shortens a Motors
Life?
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Thermal Stress
Mechanical Stress
Electrical Stress
Vol t age and Cur r ent Ti me Domai n - - PUMP #2
Cur r e nt
( A)
12/ 11/ 2003 10: 47: 48 AM
Vol t a ge ( V)
1000
600
800
400
600
400
200
200
V 1-2
- 400
- 600
0.
10
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09
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08
- 200
0
0.
07
0
- 200
- 400
- 800
- 1000
- 600
Environmental Stress
Environmental Stress
Motor Testing Benefits
Motor Reliability
Quality Control
Trending
Troubleshooting
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PROGRAM
IMPLEMENTATION
Electrical Reliability Program
Implementation Steps
• Establish a criticality ranking of the
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motors that are to be tested.
Determine frequency of testing.
Construct a database for the motors
in operation as well as spare motors.
Review failure history of motors
Identify how your motors have failed.
Identify staff to perform the testing.
Criticality & Test Frequency
Assessment
Criticality Level
Result of Failure Test Frequency
-Plant Shutdown
Safety/Environmental
-Environment Release & Safety
3 month cycles
-Large Asset Replacement Value
Mission Critical
Process Critical
Non critical
-Partial Plant Shutdown
-Significant Production
Loss
3-6 month cycles
-Process Shutdown
6-12 month cycles
-Production Loss
-No Production Loss
-System Redundancy
12 month cycles
MCE Offline Testing in the
Field
MCE Test
Instrument
MCE
Offline
Test
Leads
How we communicate
and relay information
about your motors?
Fault Zones
Power Quality
Power Circuit
Stator
Insulation
Air Gap
Rotor
Fault Zone Analysis
Power Circuit
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Power Circuit Testing
Online Emax Test – Voltage & Current

Current Imbalances & Voltage Imbalances
Offline MCE Test – Applied Voltages
Resistive Imbalance
 Inductive Imbalance

Test location – Switchgear and/or motor
Have you seen this
before?
Insulation
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Insulation Testing
• MCE Testing Only
- Resistance to Ground (Mohms)
- Polarization Index Testing
- Step Voltage Testing
• Test Location
- Switchgear
- Motor
- Cables Only
MCE
Polarization Index
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10 minute test
RTG readings graphed
every 5 seconds
Ratio of value at 10 min.
to value at 1 min.
Dielectric Absorption
Ratio
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•
•
1 minute test
RTG readings graphed
every 5 seconds
Ratio of value at 60
seconds to value at 30
seconds
Insulation
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Insulation Failure
Stator
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Stator Testing
Emax Online Tests
- Impedance Imbalance
- Current Imbalance
- Inrush/Start up tests
• MCE Offline Tests
- Inductive Imbalance
- Rotor Influence Check
- Average Inductance
Stator Failure
Rotor Influence Check Example
Stator Failure Examples
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Rotor
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Rotor Testing
Emax Online Tests
- Current Signature Analysis
- Current Demodulation
- Inrush Start/up current test
• MCE Offline Tests
- Average Inductance
- Rotor Influence Check
- Inductive Imbalance
Rotor
Cast Rotor Porosity
Rotor
PdMA Corporation
AirGap
PdMA Corporation
Eccentricity Air Gap
Testing
Emax Online Tests
•
Current Signature Analysis
• MCE Offline Tests
•
Rotor Influence Test
How do we manage this data?
Answer: Ohio CAT
Conclusion
Reduce failures & increase motor life
Reduce maintenance cost
Reduce motor repair cost
Understand condition of installed motors
Manage & communicate motor data
Test safely
Increase overall plant reliability