The Problem
An Applied Biosystems real-time PCR system required repair after its plate tray stopped moving correctly and generated mechanical loading errors. The fault prevented reliable loading and unloading through the instrument software.
Diagnostics
Mechanical and control checks isolated the failure to an optical sensor responsible for detecting tray position. The sensor was no longer providing the feedback needed for the tray mechanism to complete its movement sequence.
Repair and Verification
The optical position-sensor assembly was removed, rebuilt in-house, and reinstalled. The tray guide rails and related mechanical components were lubricated and checked for smooth travel.
The instrument was then connected to its control computer and exercised through a full software test run. Tray movement and the tested instrument functions completed normally.
Result
The real-time PCR system returned to normal operation with reliable plate-tray movement. Rebuilding the existing sensor assembly resolved the fault without requiring a replacement part.
