Maintenance, Repair & Operations

Electrical Troubleshooting Quiz — Dec. 18, 2018

Dec. 18, 2018

Why do the electric lift trucks lack power and don't run long enough?

The lift truck drivers have been complaining that the electric lift trucks lack power and don’t run long enough. The problem has been affecting operations. Additionally, the central office wants electric trucks to comprise a larger portion of each plant’s lift truck fleet, so adding more LPG trucks is not an option.

The plant engineer reviewed the battery maintenance procedure and the actual practices. He found no problems. Figuring that deep cycling causes the batteries to age faster, he issued a work order to identify and replace the 25% that were the oldest. This had only a moderate effect, and now he wants you to solve the problem.

What’s the first step you should take?

Check how each specific battery is being charged. Lift truck batteries come in different voltages (e.g., 12V, 36V, 48V). If a 36V battery is being charged by a charger set for a 12V battery, it isn’t going to charge. If the charger is set for a 48V battery, the 36V battery will cook.

Measure the charging voltage(s) of each battery charger while charging. If you’re trying to charge a 12V battery and the charger is applying 15V, that battery will cook.

Examine each battery. Are the case and connections clean? Before taking a battery off its maintenance charge, connect a digital multimeter (DMM). Then, monitor the voltage for a few minutes after disconnecting from the charger. A fully charged 12V battery, for example, should read 12.6V.

About the Author

Mark Lamendola

Mark is an expert in maintenance management, having racked up an impressive track record during his time working in the field. He also has extensive knowledge of, and practical expertise with, the National Electrical Code (NEC). Through his consulting business, he provides articles and training materials on electrical topics, specializing in making difficult subjects easy to understand and focusing on the practical aspects of electrical work.

Prior to starting his own business, Mark served as the Technical Editor on EC&M for six years, worked three years in nuclear maintenance, six years as a contract project engineer/project manager, three years as a systems engineer, and three years in plant maintenance management.

Mark earned an AAS degree from Rock Valley College, a BSEET from Columbia Pacific University, and an MBA from Lake Erie College. He’s also completed several related certifications over the years and even was formerly licensed as a Master Electrician. He is a Senior Member of the IEEE and past Chairman of the Kansas City Chapters of both the IEEE and the IEEE Computer Society. Mark also served as the program director for, a board member of, and webmaster of, the Midwest Chapter of the 7x24 Exchange. He has also held memberships with the following organizations: NETA, NFPA, International Association of Webmasters, and Institute of Certified Professional Managers.