Slitting Line Bracket Breakdown

Slitting Line Bracket Breakdown – Siemens Step 7 Programming Software, S7-400 PLC

Issue:
A fault occurred on a sheet metal slitting line involving Box 1 bracket actuators. The brackets failed to open, disabling both automated and manual operation.

Diagnosis & Resolution:
Our engineers attended site and initiated fault tracing using the system schematics. We identified the manual operation button and traced its cable to a PLC input. Using Siemens Step 7 software, we located the relevant rung of code linked to input I55.4, which was inhibiting manual bracket closure.

The input was labelled in the schematics as “Motor Side – Slide Box 1 High.” When queried, the operator was unfamiliar with the component’s location or function. Leveraging our experience with mirrored mechanical layouts, we conducted a physical inspection and discovered a pair of concealed sensors—one of which was inactive.

Upon securing the sensor on the mirrored side, the signal transitioned to high, restoring full bracket functionality and resuming both manual and automated operations.