The Benefits of an Electric Motor Testing Program
We’re all familiar with the fallout from an electric motor failure; when the production or packaging line stops, so does the company revenue. Fortunately, you can minimize the downtime and unplanned repair/replacement costs by establishing, and then following, an Electric Motor Testing (EMT) routine as a part of your comprehensive reliability program.
The main goal of any EMT program is to reduce maintenance and emergency repairs costs by increasing the mean time between failures (MTBF). With regular inspections and thorough testing protocols, most electric motor issues can be predicted, prevented, or resolved with a minimal disruption to your packaging or production lines.
While each EMT program will be unique for your business and location, there are five essential steps used by companies looking to minimize electric motor repairs while maximizing their lifecycle.
Develop a Tracking System
Never rely on the motor manufacturer’s nameplate for tracking your electric motors. Instead, attach an embossed metal tag with a specific tracking code or reference number assigned on site. You should be able to look up the motor number and see its history from the time it was delivered to your location, until you send it off to the scrap yard.
You can create a tracking system using a basic spreadsheet program. One of the perks to this option is the flexibility, you can add, delete, or rearrange the cells, columns, and rows to create the perfect tracking program for your specific business and equipment.
There’s also no shortage of facilities management and predictive maintenance apps and programs available, either. But before you commit to one platform over another, consider where you plan to be in the next 3-5 years. Could that program handle your equipment tracking needs if your business doubled, or tripled in that timeframe?
Upon Receipt Inspections
In your tracking system, the first entry for each motor should be its “upon receipt inspection.” Every motor should be checked immediately for visible damage, such as.
- Cracked or damaged cooling fins.
- Shaft not properly supported during transit.
- Transit damage from impacts or mishandling.
The second phase of a receipt inspection focuses on the quality of work performed by the motor manufacturer or repair facility.
- The grease fittings should be installed and capped.
- The nameplate must be legible.
- Check castings for cracks.
- Verify the fan shroud is correctly installed.
- Check wiring connections inside the connection box.
After passing the receipt inspection (visual), it’s time for the motor acceptance tests (electrical testing). This series of tests can detect shortcuts taken during the manufacture or repair of your electric motor. These tests normally include.
- Rotor influence check (RIC)
- Phase-to-phase testing (resistance and inductance)
- Surge testing
- “Megger” testing (no path from insulation to ground exists)
These tests can identify issues that could contribute to a premature motor failure, such as.
- Insulation weakness in the electric motor windings
- High-resistance connections
- Turn-to-turn shorts
Electric Motor Storage
Your electric motor storage area must be vibration free, since vibrations can lead to false-brinelling in the bearing assemblies. A climate-controlled environment will eliminate temperature swings, which contribute to condensation build-up within the motor.
Arrange your stored electric motors so the connection box remain accessible for testing purposes. All electric motors, whether in storage or in service, should be routinely inspected and tested. And lastly, rotating the stored motor shafts every 30-90 days (depending on the motor size) protects against rotor sag and false-brinelling.
Choose the Best Vendor and Repair Facility
Choosing the right vendor and repair facility will lead to fewer motors failing the receipt or acceptance tests while extending the MTBF to reduce maintenance costs and downtime, simultaneously.
Of course, you’ll want an electric motor vendor with decades of experience, and one that is EASA Accredited (Industry Association) since you’re trusting that shop with keeping your business up and running. In addition, the best electric motor repair facility will also provide the following but not limited to:
- Vibration analysis for current running motors to help diagnose a problem before you experience a catastrophic failure.
- Motor pulling services and equipment.
- Assistance with motor alignment.
- Help customers reduce maintenance costs.
- Tracking system assistance and possible storage of motors.