Failed Repairs

A repair that isn't done correctly is a failure waiting to happen. Some common errors include:

• Poor hygiene. Lay disassembled parts on a clean surface, such as cloth for that purpose. At every step, prevent the introduction of grit, chemical contaminants, and water. Even finger oil on contact surfaces can create problems later.
• Misapplication of lubricants. No, it's not okay to spray breakers with a handy can of spray lubricant. A spray lubricant doesn't have the "body" to adhere to high pressure points of contact. Use only the lubricant specified by the manufacturer. Don't over lubricate.
• Re-using old fasteners. For control wiring and other low-torque applications, this is usually acceptable. If you need more than a screwdriver to tighten the connection, replace the hardware.
• Misapplication of spring-type fasteners. Belleville washers are commonly misapplied. The errors are usually over-tightening or use of the wrong size. Replace after each use with the correct size, and follow the installation instructions for a reliable connection.
• Improper torqueing. Improper tightening of motor mounting bolts is a leading cause of replacement motor vibration problems. Use the torque value specified for the fasteners you’re using, not the value from a generic table.

You can prevent most "failed repair" problems by addressing potential failure causes in your repair procedures. Ask a few key questions, such as: For breaker X, what lubricants do we use? For feeder bus 06E, which Belleville washers do we use?