I think one of my five AIUs has failed. The five were daisy-chained to my TIU. When I set up my new WTIU last weekend, I daisy-chained the five AIUs to the WTIU. While using the updated DCS app, I accidentally tapped the “all” icon for accessories and then tapped “on.” As result, I turned all accessories on, including high amperage 497 and 397 coal loader motors.
Afterwards, I could not turn off several of the accessories, for example, the 497 coal loader. Through a process of elimination, I determined that AIUs 2-5 were no longer responding. AIU 1 is working normally. Turning all accessories on at the same time may have damaged either AIU 1 or AIU 2 failed. I checked all my connections and switched cables around the AIUs; however, AIUs 2-5 still did not respond. Reprogramming switches and accessories did not solve the problem.
I reinstalled my TIU, but it found no AIU’s. When using a DCS handheld, the “read” function shows whether a TIU is installed and how many AIUs are present. Is there a similar function in the app? If so, I cannot find it. If I remove AIU 1, and daisy chain AIU’s 2-5 to the WTIU, the app should indicate how many, if any, AIUs are present. If none is present that might suggest that AIU 2 is the problem unit.
If you have any suggestions, please, let me know.
