Motor Repair or Replacement Decisions

If you have filled you car up with gasoline (or diesel) lately, you know that energy is getting expensive. As equipment operators we want to make sure that we maintain the efficiency of the equipment that we maintain and operate to get the most out of the energy we purchase. The decision to repair or replace a motor with a higher efficiency one has always been a key consideration. A friend recently referred me to an article (http://www.plantservices.com/articles/2008/069.html) that challenges some of the old considerations about the repair or replace decision. The author advocates considering a high quality repair or rebuild as an alternative to replacement because the technology and methodology has greatly reduced the loss of efficiency during a rebuild. While the author makes an excellent point regarding the need to consider a rebuilt motor, I would recommend that you maintain a database of all of your motors using MotorMaster (http://www1.eere.energy.gov/industry/bestpractices/software.html#mm) and have a pre-planned approach to how you operate your motors and which ones to repair or replace to optimize your plant efficiency.

Once the determination has been made on a motor rebuild vs. replacement, please consider your selection of a motor rebuild shop very carefully. I recommend a written contract and specification of the exact standards that the rebuild should conform to. Here is a link to an industry specification for motor rebuilds: http://www.easa.com/sites/default/files/AR100-2010_1010-2.pdf. Also consider a personal tour of the motor shop to observe their work in progress and, most importantly, don't select a service provider on price alone. A loss in efficiency will cost you everyday you run the motor.

Other excellent information on motor ownership and maintenance can be found here: http://www.easa.com/sites/default/files/eemtr_repair1107.pdf