Energy & Operating Cost Savings

Maximize Your Electrical Investment - Maintaining Electrical Equipment

AS SEEN IN THE FEBRUARY 2014 ISSUE OF OIL MILL GAZETTEER

February 25, 2014

Maintaining your electrical system can have a huge impact on maximizing your investment. Inspection, cleaning, verification, and testing can extend the life of your investment.

Inspection - A periodic walkthrough and inspection is important to make certain that equipment is in good condition. It is particularly important to ensure that hazardous area equipment is in working order. Check that equipment is not damages, that all bolts and hinges are in good repair, and that the seals and wiring are in good condition as these items are important to the overall safety of your facility. Often overlooked is the facility's grounding system. Check that the grounding is operating correctly by test and inspection to be sure the faults are cleared quickly and safely.

Cleaning - Over time, equipment gets dirty. Dust build-up can interfere with equipment operation. This could mean equipment won't trip when it is supposed to, or it could short out if insulators become covered. Making sure that the mechanical components of electrical equipment are clean, lubricated, and exercised periodically will ensure they will operate when needed.

Verification - Changes to equipment settings can impact the arc flash exposure for employees and could cause additional nuisance trips and downtime for your facility. It is important to ensure settings have not been changed since equipment was installed, that it is loaded appropriately, and that documentation is up to date. Maintaining documentation ensures that your lock out/tag out programs are up to date and allows for quicker troubleshooting.

Testing - Many test could be preformed on your electrical system. The initial focus of your testing should be on critical equipment. Four common tests are infrared scans, transformer oil testing, breaker testing, and megger testing.

Infrared scans are a quick and easy way to see if equipment is showing increased heat. Areas of increased heat are often found in loose connections, failing contacts, or overloaded equipment. A yearly scan can find many issues before they become failures.

Liquid-filled transformers should have periodic oil sample tests to monitor for signs of internal breakdown. Since the loss of a transformer would cause a plant shutdown, monitoring its condition is an important predictive maintenance process.

Breaker testing ensures that breakers will operate as expected and that internal components of the breaker are intact and properly calibrated.

Wiring can also be tested through Megging or Hi-Pot testing. These tests ensure that the wire insulation is intact. One caution with this type of testing is that it does stress the wire, which could result in failure. Newer testing methods, such as VLF (very-low frequency) testing, are less destructive and gaining popularity.

Finally, emergency lighting should be inspected periodically so that you can be sure it will function when it is needed for people to safely exit the facility. Check that batteries or generators are maintained and tested so they stand ready when needed.

Maintaining your system is one the biggest impacts you can have to maximize your electrical investment. NFPA (National Fire Protection Association) 70B and NETA (International Electrical Testing Association) Maintenance Testing Specifications are good references for your electrical maintenance program.