Dear fellow researchers,
We are currently operating a Philips XL30 Scanning Electron Microscope (SEM) equipped with a tungsten filament and have encountered a significant issue.
Recently, our SEM experienced an air pressure drop due to a compressor failure while the system was in operation. This incident triggered an error message: "Fatal PCLB Error: Pressure below 3 bar."
Following the repair of the compressor, we have been unable to activate the high tension (HT). When attempting to engage the HT via the software interface, we receive a "HT Button disabled" message. Additionally, pressing the HT button on the control panel yields no response, despite the system achieving the requisite vacuum level of 10^-6 bar. Notably, the indicator light on the HT button also fails to illuminate.
Our troubleshooting efforts have included inspecting the relays on the rear panel and tracing the electrical pathway of the HT button as far as our limited electrical schematic allows. However, our investigation terminates at one of the circuit boards due to incomplete documentation.
We would greatly appreciate any insights or experiences from those who have encountered similar issues. Furthermore, if anyone has access to comprehensive electrical diagrams for the Philips XL30 SEM, sharing these resources would be immensely helpful.
Thank you for your assistance. Best regards, Nicolai Schneider
The best source of information would be the manufacturer; whether or not you have a service contract. Phone them up and see if a Service Engineer can help you with a fix with your above information (I do this fairly regularly).
We have solved the problem. It looks like A box-shaped cover is fixed to the back of the electronic column with two screws. Beneath this cover is a microswitch, actuated by a pressure rod attached to the cover housing the Wehnelt cylinder of the electron gun. The microswitch, which signals to the SEM whether the cover is fully closed, was defective. After replacing the microswitch, the HT switch now reacts properly. It appears that the occurrence of this fault, along with the pressure drop, was merely a coincidence without any causal relationship.
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Materials Science