911

SHORTED SCRS/DOUBLER FAULT

Otis · DSD 412 DC Elevator Drive

What does 911 mean?

One of the SCR/Doubler packs has a short circuit between the SCRs. This condition is checked only upon request through the PCU #998 Diagnostics CDU function. The optional handheld PCDU can also identify the specific SCR pair that is faulty. A DSD Power Down is required.

Common Causes

  • A short circuit has occurred within an SCR/Doubler pack.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Initiate a DSD Power Down for the drive.

  2. 2

    Run the PCU #998 Diagnostics CDU function to identify the specific shorted SCR/Doubler pack.

  3. 3

    If available, use the optional handheld PCDU to identify the exact shorted SCR pair.

  4. 4

    Replace the identified shorted SCR/Doubler pack.

Browse all codes in this manual (48)
Verified technical data. Last updated: March 2026

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Source: Otis DSD 412 DC Elevator Drive