How to care for your electric motor

Discover all the secrets of effective electric motor care here, including tips on handling, storage, installation and operation.

In order to get the highest level of performance and longest possible service life from your electric motor, there are certain steps you can take. Here’s Gibbons’ guide to looking after your motor.

Handling and storage

Wherever possible, store your motor in its normal operating position. The area should be clean, dry and free from vibration.

Motors stored for long periods may have been exposed to moisture. If this is the case then before installation, check the insulation resistance of the windings against the frame (earth) with a Megger (maximum DC voltage 500V).

Installation and operation

When installing your electric motor, it’s vital to check:

• Rated voltage and frequency
• Ambient temperature does not exceed 40°C, unless motor specially designed to withstand extreme heat
• Altitude does not exceed 1,000 metres above sea level
• Correct connection (see diagram inside terminal box)

Ensure that air can flow in and out unhindered. The space between the air intake and the nearest wall should be roughly equivalent to the shaft height of the motor. Design foundations to ensure that when the motor and driven machine are running that vibration is avoided.

Condensate drain plugs must be located at the lowest point of the motor casing. Clean the motor shaft with a solvent prior to mounting the transmission parts.

You must secure your motor to a level surface otherwise you risk causing mechanical deformation.

Unless previously agreed with your supplier, rigid coupling systems are not allowed. Use only coupling systems that are elastic with respect to centre offset, angular displacement, longitudinal shift and torsional strain.

If direct coupling is employed, check centre offset and angular offset with screwed-on test arm and dial gauge.

Be sure not to exceed the following deviations:

•  Centre offset (radial measurement) 0.03mm in two-pole motors, 0.05mm in motors with more than two poles.
• Angular offset (axial measurement) 0.1mm.

Alignment should always be checked at normal operating temperature. If your application involves belt transmission, avoid unnecessary wear on bearings by positioning the shafts parallel to one another and keeping the pulleys perfectly aligned.

Ensure the belt tension is stretched enough to prevent slipping. If the pulleys are too small then the motor shaft is likely to bend – this must be avoided.

Cleaning, lubrication and maintenance

Regular checking of the starting system during preventative maintenance is recommended in order to prevent serious issues such as corrosion and poor electrical contact.

Regularly clean the intake and outlet openings as well as the channels between the cooling fins – this prevents clogging which can lead to overheating.

Some motors have sealed bearings and are not designed to be lubricated except when disassembled. Others can be periodically greased or may feature an oil sump, so consult your motor’s specification to be certain.

Gibbons Group not only distribute high-efficiency electric motors, we also provide a comprehensive rewind and repair service, so if the worst should happen then we’re here for you. For all enquiries, call 01621 868138, email paul.scott@gibbonsgroup.co.uk or visit our Electric Motors and Rewinds & Repairs pages.