Is it the Pump or the Motor?
In the classic battle of root cause analysis, it often comes down to electrical vs. mechanical with the motor or the pump being the primary suspects. A variety of tools…
Tip of the Week
5th Harmonic and Magnetic Center
Running a motor uncoupled will pull the motor rotor into a magnetic center, often marked on the shaft to ensure that the rotor is lined up on the magnetic center…
Keep an “EYE” on Your Rotor
Squirrel cage induction rotors with broken or cracked bars, if left unattended, will worsen with every start. Finding these issues early and taking action to repair the problem will prevent…
Motor Tripped?
Analyzing the motor current for transient In-Rush peak and Start-Up time is a standard approach to troubleshooting a tripped motor. An instantaneous trip might indicate a stator or trip set…
WRM – Pole Pass Frequency With No Rotor Bars?
A Wound Rotor Motor (WRM) is an induction motor typically found in cranes, hoists, compressors, conveyors, mixers, fans, blowers, mills, and pumps. However, unlike the very common squirrel cage induction…
ANSI/EASA Standard AR100
A commonly used and well-respected standard in the electric motor testing industry is the Recommended Practice for the Repair of Rotating Electrical Apparatus (AR100). Furthermore, this standard is provided by…
New Year Motor Reliability Tip – 2023
A new year reminds us it is time for an annual review of our test measurement alarm setpoints. We should annually review the setpoints to make sure they are not…
Humidity and Insulation Resistance
Humidity, like temperature can affect insulation resistance-to-ground measurements. Depending on the humidity level and ambient temperature, moisture may settle onto the cables, windings, motor frame, etc. This will affect the…
From Quality Assurance to Troubleshooting… Don’t skip the Baseline!
Equipment and Human Resource limitations such as technicians and analysts, play a role in our everyday lives as maintenance and reliability professionals. We are often in a position where we…
Split Peak at the 5th Harmonic
When analyzing current signature analysis, like the PdMA EMAX Rotor Evaluation Test, the primary focus starts at the Pole-Pass-Frequency (Fp) sidebands around line frequency. Elevated Fp sidebands can be indicative…
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