A motor failed at your facility. Now what?
In an earlier blog, I outlined six best practices of a motor management plan. This post takes a deeper look at how a solid motor failure policy limits your risk exposure.
When a motor fails, you have two options: to repair it or replace it. The best option for a given motor depends on a variety of factors. Today’s expense to repair or replace plays a relatively small role in the big picture.
Knowing your game plan before a motor fails enables you to make informed decisions that consider safety, risks, and costs. A motor failure policy helps you manage risks and control expenses simply by making your motor management decisions data-driven. Based on your organization’s needs, the following guidelines may aid your decision-making process:
- Determine your horsepower breakpoint.
Based on your electric rate, repair cost, distributor discount on new motors, the efficiency of your failed motor, and its annual run-hours, it may be more cost-effective to replace your motor than repair it. Once a year, evaluate these costs for common motor sizes and calculate the break-even point where it becomes more cost-effective to repair a motor. These calculations inform your facility’s particular rule of thumb — i.e., that motors falling below this horsepower breakpoint (e.g., 50 Hp) are throw-away (replace) and everything at and above it, repair.
I recommend including full life-cycle costs and your company’s payback or IRR criteria in this analysis. After all, energy expenses comprise the clear majority (90% – 97%) of a motor’s life-cycle cost. Even a one-point rise in efficiency translates into tremendous savings over the motor’s service life. Since many motors lose efficiency when repaired (that is, unless your shop is ANSI/EASA-accredited), considering full life-cycle costs may sway your decision to repair vs. replace. Since new motors will likely last longer than a repaired motor, consider costs that the new motor will incur over the expected lifetime of the repaired motor.
- Identify improperly spec’d motors.
Since the capital cost on new motors can be prohibitive, I recommend using motor failures—this point in time where you must make a motor management decision—as an opportunity to evaluate the appropriateness of a motor in its application.
Identify motors and locations with frequent failures, then perform (or ask your preferred repair shop to perform) a Root Cause Failure Analysis (RCFA). Once you identify the reasons behind chronic motor failures, you can build the business case and initiate appropriate corrective action. For example, if your harsh environment causes frequent motor failures, replace the motors with severe duty motors — increasing motor reliability and reducing downtime. Similarly, a motor with damaged windings may indicate an electrical issue at the plant.
Replacing oversized, under-loaded motors — those running at less than 50 percent of their capacity — with smaller, premium efficient motors that better match your load requirements reduces the cost of your capital expenditure and increases the motor’s operating efficiency, reducing your energy spend.
- Communicate your plan.
For critical motors, the cost of downtime will far exceed the cost to either repair or replace your motor. But that doesn’t mean you don’t have time to apply these principles.
To ensure business continuity, I recommend making your motor failure plan transparent to all equipment operators and maintenance technicians. Place easily identifiable tags on each motor to communicate the correct course of action upon that motor’s failure. Use the tag to identify whether to repair or replace this motor. If replacing, indicate where to find its spare, whether on-site or stocked off-site with a contracted vendor. At the very least, establish a retainer agreement with your preferred motor supplier and repair shop to respectively ensure local availability of spares and guaranteed repair turnaround times.
Establishing a solid motor failure policy helps you reduce downtime, increase productivity, and save money. To learn more on how our software can help you monitor your motors — and proactively plan for future motor failures — contact us at info@motorsatwork.com.