Have you checked the insulation system of your electric motor recently?
Conducting regular preventative maintenance helps companies improve the longevity of their electric motors — reducing the amount you need to spend on repair, or replacement solutions. While many components contribute to the lifespan of a motor (like the bearings, and rotors), the insulation system is one of the most prone to failure.
In fact, the insulation system of an electric motor is so critical that it has its very own diagnostic test — known as “winding analysis.”
Why Do Engineers Need Winding Analysis?
The first thing to note about winding analysis is that it’s a form of non-destructive testing. This means that engineers don’t need to take a motor apart to ensure the insulation system is working properly. Using innovative techniques and tools, motor winding analysis can detect insulation failures before an electrical breakdown occurs — giving businesses the chance to correct faults, and take preventative action.
Winding analysis enables engineers to discover potential problems early, reducing the risk of serious problems when harsh work-site conditions (and other elements) weaken the insulation system. The result is greater efficiency, reduced heat build-up, and a slower breakdown of the motor overall.
Performing a Winding Analysis
Typically, companies approach highly-skilled professionals to conduct a winding analysis — look for someone who has trained extensively to understand the complexities of the technique. A professional can create a report about the internal workings of the motor; displaying potential issues, even if the equipment hasn’t shown any noticeable signs of damage. When conducted by a trained professional, a winding analysis can be enough to detect the slightest imbalance between aspects of a motor insulation system.
Usually, winding analysis is performed when there’s scheduled maintenance, or downtime for the machine — this saves companies from having to shut down their processes at a time critical to business operations. The process involves the use of three equally important tests, to establish the condition of your winding insulation:
- Online Tests — used to evaluate Voltage/Amps per phase, and the Rotor Bar Test
- Electrom TIG 12-D Offline Tests — a series of tests including phase-to-phase resistance reading evaluation, ground insulation testing to evaluate micro-amp leakage at increasing DC voltages and time intervals, Surge Comparison and Partial Discharge testing.
The combination of these tests can provide evaluation information to reduce motor failure, lost production, and even safety hazards. Ideally, the test information may indicate no further action needed, winding insulation reconditioning is indicated or the winding insulation replacement should be scheduled. The same testing program can also troubleshoot problems that appear to be causing inefficiency within the motor; or simply ensure that the motor windings aren’t the source of a complete machinery failure.
Some engineers use winding analysis as a trending tool, to monitor the complete dielectric strength of insulation over a certain period of time — therefore informing more conclusive preventative maintenance programs.
When Should You Use Winding Analysis?
Your best bet is to use winding analysis as part of your preventative maintenance program; because it’s often simpler (and less expensive) to correct a problem during its initial phases, rather than after it’s become catastrophic. In electric motors, winding failures can occur for a variety of reasons — including everything from variations in load, to environmental conditions, and more.
With motor winding analysis as part of your predictive maintenance strategy, you can avoid disruption and failure; and ensure your machinery remains in excellent condition longer, improving your company’s profit and productivity over time.
How often do you conduct a winding analysis on your motor? Do you use it with other preventative maintenance measures? Let us know in the comments below!