Tips for keeping DC motors healthy

An effective maintenance program prolongs the lifespan of DC motors and prevents expensive and unnecessary repairs.

By David Manney, L&S Electric January 5, 2017

Cutting operating costs while increasing the bottom line is a sensible move for any facility. This is why an effective maintenance program is essential to achieve these goals. Because DC motors are more tedious and critical to maintain compared to AC motors, creating an effective maintenance program that prolongs their lifespan and prevents expensive and unnecessary repairs is crucial.

Perform regular visual checks

Make a habit of monitoring a DC motor’s condition. Keep a record of any performance inconsistencies. This reveals a significant problem bound to happen in the future. Inspect the motor’s appearance and look for corrosion or dirt buildup. These are telltale signs that it is not in top condition.

Also, check for a burned smell originating from the motor windings. This reveals an overheating problem. Damages occur to the motor winding under such conditions, so be sure to conduct a winding test to detect issues that may need immediate solutions.

It is also important to prevent dirt from accumulating on every surface of the motor. Debris functions as a heat insulator and triggers heat damage. This is why the cooling fan should be checked, as well as any dirt-blocking passages. Use a rag or vacuum the passages to remove blockages.

Check for vibrations or strange noises

Perform an auditory inspection of DC motors and their components. Listen for sounds or vibrations during normal operations. A noise in the mechanical or electrical parts of the motor is a sign of poor bearings, loose windings, misalignments or imbalances. Vibrations may reveal items caught in the shroud or vent. Brush sparking and overheating also may result due to constant vibrations.

Since noises either pertain to a mechanical or electrical issue, determine which one it is. Vibrations that take place even when the motor is not powered present a mechanical problem. Those that stop upon disconnecting the motor from a power source present an electrical issue.

Keep the brush and commutator in great condition

A DC motor can perform well if its brushes and commutator are well-maintained. Inspect the brush connections making certain they are free from chipping or debris, aligned properly, clean, and secure. If old brushes appear worn when compared to new ones, immediately replace them.

A commutator must have a smooth, polished appearance. Scratches and grooves signal a brush sparking or excessive wear. If this is the case, replace the commutator. If dirt is accumulating, remove it using a fiberglass cleaning brush with an electric motor cleaner.

Keeping a DC motor in optimal condition helps extend its life and can spare a facility from unnecessary repair costs. Incorporate these techniques into a maintenance program. Doing so avoids massive headaches due to unplanned downtimes and lower productivity rates. 

– David Manney is a marketing administrator at L&S Electric. This article originally appeared on L&S Electric Watts New Blog. L&S Electric is a CFE Media content partner.

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