Differences

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--- installation_fp_sci [2017/06/20 17:15]
pereira [Vent focal-plane chamber]
+++ installation_fp_sci [2018/04/11 16:11]
pereira [Pumping focal-plane chamber]
@@ Line 3: / Line 3: @@
 ===== Vent focal-plane chamber =====
   * Open the [[hv_bias|HV Remote Control]] GUI and ensure that the focal-plane detectors are unbiased
-  * Open the [[gas_handling_system#labview_control_program|Labview gas handling system]] and verify that there is no gas in the CRDCs and IC. Open valves **4** (IC supply), **5** (IC bypass), **6** (IC focal-plane bypass), **20** (CRDC supply), **21** (CRDC bypass), and **22** (CRDC focal-plane bypass). The rest of the valves should be closed
+  * Open the [[gas_handling_system#labview_control_program|Labview gas handling system]] and verify that there is no gas in the CRDCs and IC. Open valves **4** (IC supply), **5** (IC bypass), **6** (IC focal-plane bypass), **7** (Ion Chamber vent), **20** (CRDC supply), **21** (CRDC bypass), and **22** (CRDC focal-plane bypass) and **23** (CRDC vent). The rest of the valves should be closed
   * Ensure that the manual venting valve located on the south side of the chamber is closed (see figures below)  {{:wiki:fp-venting-valve-Daniel.jpg?350|FP chamber manual venting valve}} {{:wiki:fp-venting-valve.jpg?350|FP chamber manual venting valve}}
   * Ensure that the FP ion gauge (I264IG) is off (see details [[vacuum_control|here]])
@@ Line 11: / Line 11: @@
 {{:wiki:fp-pirani.jpg?350|FP chamber manual venting valve}}
   * Wait until the chamber is vented (few hours). The **I261PG** Pirani Gauge should read slightly above atmospheric pressure (due to the dry N2 flow pumped to the chamber). The window **VENT STATUS** in PanelMate should display "VENT VALVE OPEN". The window **PUMPDOWN STATUS** should display "PUMPDOWN STOPPED"
-  * When the chamber is fully vented, select **VENT STATUS** and click **STOP VENTING PROCEDURE**. This will automatically close the vent valve ***I260VV*
+  * When the chamber is fully vented, select **VENT STATUS** and click **STOP VENTING PROCEDURE**. This will automatically close the vent valve **I260VV**
   * Close the manual vent valve
@@ Line 45: / Line 45: @@
 ===== Pumping focal-plane chamber =====
   * Make sure that the pressure-relief valve and the manual vent valve (see above) are closed.
-  * Make sure that manual valve of the mechanical pump is opened {{:wiki:ManualValve-fp.jpg?350|Manual valve pump}}
+  * Make sure that manual valve of the mechanical pump is opened (the valve **I260RV** will be automatically opened in the next step) {{:wiki:ManualValve-fp.jpg?350|Manual valve pump}}
-  * Open PanelMate **S800vac** and go to page 07. Make sure
+  * Open PanelMate **S800vac** and go to page 07. Make sure that the venting valve **I260VV** is closed (see last step of the [[#Vent focal-plane chamber|venting process]] described above)
   * Select window **PUMPDOWN STATUS** and click on button **START PUMPDOWN**. The **PUMPDOWN STATUS** and **VENT STATUS** windows should display "PUMPDOWN IN PROGRESS"
-  * Wait for some hours until vacuum is good
+       * After the rough valve **I260RV** is automatically open, the mechanical pump will start pumping.
+       * The pressures in the mechanical pump (from **I259PG**) and beam chamber (from **I261PG**) will jump momentarily to very high values. They should go down slowly after few seconds (otherwise, the chamber is not properly closed).
+       * When pressure in the chamber (from **I261PG**) gets below 100 mTorr (at least 30 min), **I260RV** will close. Foreline valve **I260FV** will open followed by the turbo gate valve **I260GV**.
+  * Wait for few hours until vacuum is good. You can then turn on the ion gauge **I264IG**

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