Otis · DSD 412 Elevator System
This fault is detected by the PCU Diagnostics function (Function #998) and indicates that one or more SCRs (Silicon Controlled Rectifiers) or doubler packs within the DSD 412 drive are open, meaning they are not conducting current as expected.
Click steps to track your progress.
Remove power from the drive.
Consult Section 5, MAINTENANCE, to identify and replace the open SCR(s).
Repeat the PCU Diagnostics function to confirm the issue is resolved.