CS0401 Stator - MCEMAX™ Identifies Turn-to-Turn Faults
Motor reliability is critical for this large fossil fuel electric generating station located in the southeast United States. This facility uses the PdMA MCEMAX™ tester for predictive maintenance on both energized and deenergized motors. Click here to read more.
CS0402R Rotor - EMAX Diagnoses Broken Rotor Bars in 2 Pole Motor
Florida Power & Light Company (FPL) is an electric utility company based in Juno Beach, Florida. During routine EMAX testing in June 2003, Motor Engineer Enrique Rodriguez observed that the peak level of the pole pass sideband was 0.7419, which exceeded the alarm set point of 0.3. Rotor bar problems were suspected, however, when vibration analysis was performed the results indicated a healthy motor. Click here to read more.
CS0404 VFD - EMAX Identifies Misfiring Transistor in a VFD
A utility has four identical motors all driven by VFD’s. One motor runs well at lower frequencies, but develops a vibration when it reaches a high frequency level. The drive manufacturer suggested checking for motor insulation degradation. Click here to read more.
CS0801 Stator - RIC Diagnoses Stator Fault In New Motor
During the practical portion of the Introduction to MCEMAX™ course a brand new motor was brought in for testing. The motor was destined to replace another unit that was presenting bearing problems during routine vibration testing. Click here to read more.
CS9111 Power Quality
During routine maintenance, EMAX dynamic testing was performed on a motor driven by a variable frequency drive. Testing was performed from both the load and line side of the drive. The data collected on the load side indicated an abnormal current waveform on all three phases for a six-pole rectifier. Click here to read more.
A large vacuum pump motor was discovered to be running at higher than normal temperatures. Vibration data was checked and it was determined that levels were elevated as well, though readings were not conclusive enough to identify the source of the fault. PdMA was called in to perform EMAX testing. Click here to read more.
A wound rotor motor was sent for a routine overhaul. Before reinstallation, quality assurance testing with MCE was performed. The rotor failed the polarization index test and the inductive imbalance was 99%. Click here to read more.
CS9603 Power Circuit
While on third shift, a jet water motor was shut down for standard maintenance operations. After completion and on a restart, the primary bus circuit breaker tripped. Repeated start attempts produced similar results. Click here to read more.
CS9604 Power Circuit This motor was running hotter then expected and exhibited excessive vibration. A similar motor, Chiller #2, was tested at the same time and provided "normal" readings for comparison. The Space Shuttle was scheduled for an immediate launch, limiting the test window. Therefore, the initial readings were taken with the power factor and surge capacitors still in the circuit. Click here to read more.
After finding unacceptable vibration levels of 4 Mils on a large compressor motor, attempts were made to balance the rotor with a 2-lb. weight. Initially, the weight reduced the vibration to an acceptable 1.5 Mils. However, levels climbed again until they reached 10 Mils at no-load. Several technologies were employed to locate the source but provided no conclusive results. Click here to read more.
While operating under normal load, this 1000 hp coke heater feed pump tripped and opened two fuses. The maintenance history showed that this motor had been rewound eleven months earlier at a cost of $24,000. Click here to read more.
DC Commutator Testing
This case study demonstrates the importance of using advanced technologies for testing critical motor components. During a routine DC motor recondition, an Alabama motor shop using PdMA's MCE™ bar-to-bar tester potentially saved a southern paper mill hundreds of thousands of dollars in unexpected motor repair costs and downtime. Click here to read more.
Online and Offline Motor Analysis
During routine EMAX testing in June 2003, it was observed that the peak dB level of the pole pass sideband was 0.7419 dB, which exceeded the alarm set point of 0.3 dB. Rotor bar problems were suspected, however, when vibration analysis was performed the results indicated a healthy motor. Click here to read more.
Desbalance Resistivo Anormal
Durante rutina de MCE se detecto alto desbalance resistivo en prueba estándar realizada desde MCC. Haz click aquí para leer más.