To solve the potential lubrication problem presented in Part 1 of this series, think about the fact this system is pumping a viscous fluid that changes viscosity in response to changes in temperature. This facility’s normal temperature swings might not seem like much, but they may cause the problems. Unless the production machinery is in a room with tight temperature control 24 hours a day, this “electrical problem” is probably a temperature-related viscosity problem.
Since you’ve ruled out other likely causes, this one should be high on your list of suspects. While your electrical training didn’t make you a lubrication expert, you now must address the lubrication issue of you are going to repair this system.
The first place to look is in the system documentation. What type of grease is this system rated for, and what type is it actually using? For example, it may be using NLGI#2 grease when it’s designed for the less viscous NLGI#1 grease. That would explain everything, and changing to a compatible (same base) grease of the correct viscosity would complete this repair.