We have a 300 ton (refrig.) CVHE Trane chiller with a Reliance adaptive frequency drive. We can't start the unit. We traced the problem to the Rockwell Automation 485 comm module. This device is especially made for Trane corp's adaptive frequency drives by Rockwell. Looking at the board Q1, U3, and U5 took some heavy duty heat. Has anybody got any experience with Rockwell's RS485 DF1 comm modules? What could cause this type of failure (these are expensive units!).
hughes838
485 Comm circuit board
Re: 485 Comm circuit board
