Ask These Questions Before Trusting a Repair Shop with Your Motor - HECO

Are you sending the electric motors and equipment that serve as your operational lifeblood out to a repair shop you haven’t evaluated?

The urge to get things off our desks and off our plates can lead to short-sighted decision making. It’s easy to send equipment out to the vendor who delivers weekly donuts, but it might not be in your plant’s best interest since being top-of-mind and having top-of-the-line capabilities do not always go hand in hand.

There are hundreds, if not thousands, of motor repair shops that will knock on your door and promise that they can handle everything in your plant from electrically testing your motor and lifting it to providing documentation before and after the motor repair. Electric motors are expensive, and specialty motors are even more expensive and have long lead times. Do yourself and your company a favor and visit the shop before you send something to them.

Knowing what to ask about and evaluate will help you navigate the vetting process. Whether you leave the assessment to HECO or ask the tough questions yourself, there are a number of questions to ask a prospective repair shop before entrusting them with your electric motor systems.

Logistical & Technical Considerations

Make sure the repair shop has the ability to handle your equipment and the expert ability to test and restore it by asking:

• Do you have a truck big enough to haul the motor or do you contract transportation out?
• Do you have sufficient insurance to cover the replacement cost of a motor if there is an accident and the motor is damaged or destroyed?
• Once the motor arrives at your shop, do you have the crane capability to safely lift the motor off the truck?
• After unloading, are you able to perform full voltage testing or do you just use equipment that gets it “close enough?”

After unloading and testing the motor, it’s time for cleaning. Be sure to ask:

• Do you have the equipment required to clean the motor safely with a crane large enough to lift the components in the cleaning booth?
• Is your oven large enough to properly bake the rotor and stator?
• Does your oven have chart recorders to prove what temperature and length of time the components were baked?
• Once everything is baked out, do you have a lathe large enough to make the repairs to the rotor or a balance machine large enough to spin the rotor?
• Is your testing and measuring equipment calibrated on a timely basis? More importantly, is your shop EASA Accredited?

Let’s explore rewinds a bit. Ask the shop:

• Does the stator require a rewind?
• Do you have a burnout oven large enough for the stator?
• Can you perform before and after burn core loss tests with an infrared camera?
• Are your burnout ovens equipped with chart recorders to ensure the temperature does not exceed the maximum temp of the lamination insulation?

Once a stator has been burnt out and pre- and post-burn core loss tests have been done, it’s important to know how the repair shop would proceed by asking:

• Do you have the experience to take the winding data and verify it is correct for that design?
• Do you have a VPI tank or is that being farmed out, too?
• Does your coil supplier provide an insulation system that is compatible with your VPI resin?

After the coils have been supplied by a reputable supplier, winders with enough experience to do the job have been utilized, the stator is rewound and has been VPI’d and baked, the testing process is key. Evaluate the repair shop’s capabilities by asking:

• Will I, as the customer, play a role in what voltage levels the stator is tested at?
• Do you document the tests and will you provide me with the final report?

Don’t forget to ask about what happens when all is going well, and the motor is assembled and being test run.

• Do you have adequate vibration data collection equipment?
• Is the motor being run at full voltage just like it will be in my plant? For example, running a 4,160-volt motor at 2,300 volts is not a full-voltage test run.
• How long will the motor be run for testing?
• Will it be run long enough for the bearings temperatures to stabilize?
• Do you provide a complete final motor report?

We could literally go on for pages on what to look for in a repair shop. The salesman being a nice guy who brings in donuts is not enough to deem a shop worthy of sending a motor worth hundreds of thousands of dollars or even an inexpensive motor with extreme criticality to. Do yourself a favor and know where your motors are going.

All Systems Go

HECO has been in business since 1959, bringing decades of experience and expertise to servicing, selling, monitoring, and storing electric motors and rotating equipment to each project.

Contact us to put our expertise to work for you. We can help you evaluate vendors and avoid costly setbacks, delays, and compromised repair quality.

Posted in Equipment Management, Repair