While inspecting bus duct for thermal anomalies can be challenging, it is certainly not impossible. The primary concern is the thermal gradient one encounters that often masks the severity of a high resistance connection. If, however, you take good care to understand the physics behind what is creating this gradient, you'll soon realize that the temperature detected on the outside surface of the duct is often times much warmer on the interior at the point of failure. Knowing this helps the thermographer better understand the severity of the problem and allows them to better diagnose problems detected on a bus system.

Read this month's tip on considerations for inspecting bus duct.

Tip Provided By: Jim Fritz, The Snell Group