Bad maintenance practices tend to sneak into the way things get done. Here are two more items to guard against:
Bad Practice #6 — Leaving Motor Starters Out of Motor Preventive Maintenance Programs
A motor is really a system (see the NEC, Figure 430.1 for a simplified overview). Conducting motor winding insulation resistance tests and greasing the thrust bearing are good, but they aren't motor maintenance. The starter has its own detailed maintenance procedure, as do other system components. A failure at the starter can mean far more damage than just loss of the motor.
Bad Practice #7 — Engaging in Guesswork Repair Follow-Up
Following a repair, it's a best practice to perform PM before returning the equipment to service. Unfortunately, this often means performing what can be done quickly and easily so you can check off the box. Instead, make a PM list based on potential problems most highly correlated to the failure. The ability to do this accurately depends upon familiarity with the equipment, which is yet another reason to have different techs train deep on different equipment.
