Table of Contents

Venting/pumping Intermediate Image box and filling PPACs with gas

The procedures to vent/pump the S800 Intermediate Image box, and/or filling the PPAC detectors with gas must be done carefully to ensure that the PPACs are not damaged. For instance, before venting the chamber, we have to make sure that the PPACs are empty and equalized with respect to the vacuum in the chamber. In order to avoid errors, an automated gas handling system (II-GHS) was designed to perform these tasks safely. The system is schematically illustrated in the figure below. It shows the status of the valves (red: closed, white: open) when the intermediate image chamber is under vacuum and the PPACs are filled with gas (NOTE: This figure was taken from the A1900 GHS included in Barney. A similar GUI for the S800 II PPACs is not yet available):

Gas Handling System of S800 Intermediate Image

The II-GHS equipment (valves, flow-meter, pipes, isobutane gas bottle. etc.) are located on the west balcony of the top level in the S3 vault (see figure below):

Gas Handling System of S800 Intermediate Image

Vent Intermediate-image chamber

Requirements: PanelMate files S3_Gas_Handling and S800Vac

S800vac Panel Mate.

Pumping Intermediate-image chamber

Requirements: PanelMate files S3_Gas_Handling and S800Vac