User Tools
playground:alpha
Differences
This shows you the differences between two versions of the page.
| Both sides previous revision Previous revision Next revision | Previous revision Next revision Both sides next revision | ||
|
playground:alpha [2010/07/16 20:26] 184.57.89.126 |
playground:alpha [2010/07/16 20:32] 184.57.89.126 |
||
|---|---|---|---|
| Line 17: | Line 17: | ||
| You need to determine what the state of the source is before you do anything. Depending on the electrical and vacuum status the source will be starting from cold, warm, or standby. | You need to determine what the state of the source is before you do anything. Depending on the electrical and vacuum status the source will be starting from cold, warm, or standby. | ||
| - | The first check you need to make is on the vacuum status of the source. The source pressure should be less than 5x10-6 torr. If it is not find out why before going any further. | + | The first check you need to make is on the vacuum status of the source. The source pressure should be less than 5x10<sup>-6</sup> torr. If it is not find out why before going any further. |
| If the control power for the machine, and/or for the source are off, or if the sodium canal supply is off or at zero current, you are starting from the cold state. | If the control power for the machine, and/or for the source are off, or if the sodium canal supply is off or at zero current, you are starting from the cold state. | ||
| Line 38: | Line 38: | ||
| 1. Check the vacuum in the low energy extension is less than 5x10<sup>-6</sup> torr then open the tube gate valve on the ion source vacuum control panel. | 1. Check the vacuum in the low energy extension is less than 5x10<sup>-6</sup> torr then open the tube gate valve on the ion source vacuum control panel. | ||
| - | 2. Check valve on gas supply bottle is open and regulator set for ~5 psig. Note this will be the case unless work has been done on the gas supply systems, the supply bottle is very low (causing the regulator to read high), or you are changing between 4He and 3He. See instructions below on running 3He. If is suspected that there is air or another contaminant in the gas lines then they should be roughed out and purged three times using the roughing pump on the leak checker. | + | 2. Check valve on gas supply bottle is open and regulator set for ~5 psig. Note this will be the case unless work has been done on the gas supply systems, the supply bottle is very low (causing the regulator to read high), or you are changing between <sup>4</sup>He and <sup>3</sup>He. See instructions below on running <sup>3</sup>He. If is suspected that there is air or another contaminant in the gas lines then they should be roughed out and purged three times using the roughing pump on the leak checker. |
| On the way back to the control room: | On the way back to the control room: | ||
| Line 48: | Line 48: | ||
| 1. Turn source magnet up to ~0.2 A. (likely already set, and it can be as high as 1 A) | 1. Turn source magnet up to ~0.2 A. (likely already set, and it can be as high as 1 A) | ||
| - | 2. Turn up the source gas until the pressure on the source tc gauge is between 300 and 500 microns (sometimes higher pressures are needed to start the source). | + | 2. Turn up the source gas until the pressure on the source tc gauge is between 300 and 500 microns (sometimes higher pressures are needed to start the source, but the source will run as low as 150 microns and the lower the pressure the better the quality of the beam and the less gas is used: a consideration when running <sup>3</sup>He). |
| 3. Set the Arc Voltage to 150 V. | 3. Set the Arc Voltage to 150 V. | ||
| Line 280: | Line 280: | ||
| ** 3He operation ** | ** 3He operation ** | ||
| - | This assumes the source is running on 4He already and that the regulator on the 4He bottle is set for no more than 5 psig. | + | This assumes the source is running on <sup>4</sup>He already and that the regulator on the <sup>4</sup>He bottle is set for no more than 5 psig. |
| Turn down the source gas until the pressure on the source tc gauge is ~10 microns.� Stop pressing the button when the pressure is 100 microns to allow the tc gauge to catch up.� The pressure response is delayed.� Do not over-drive the source gas control as it could damage the leak valve. | Turn down the source gas until the pressure on the source tc gauge is ~10 microns.� Stop pressing the button when the pressure is 100 microns to allow the tc gauge to catch up.� The pressure response is delayed.� Do not over-drive the source gas control as it could damage the leak valve. | ||
| - | Go out to the vault and make sure a 3He bottle is ready for use. It MUST have its main valve closed at this point. | + | Go out to the vault and make sure a <sup>3</sup>He bottle is ready for use. It MUST have its main valve closed at this point. |
| - | Shut off the manifold valve near the floor that is connected to the 4He. | + | Shut off the manifold valve near the floor that is connected to the <sup>4</sup>He. |
| Start the roughing pump that is attached to the manifold and open the manifold valve leading to the pump. | Start the roughing pump that is attached to the manifold and open the manifold valve leading to the pump. | ||
| - | Open the manifold valve to the 3He regulator, also open the valve on the regulator output. | + | Open the manifold valve to the <sup>3</sup>He regulator, also open the valve on the regulator output. |
| Rough for a minute until the TC gauge on the pump is about 10 microns. | Rough for a minute until the TC gauge on the pump is about 10 microns. | ||
playground/alpha.txt · Last modified: 2012/11/27 08:57 by jacobs
Page Tools
Except where otherwise noted, content on this wiki is licensed under the following license: CC Attribution-Noncommercial-Share Alike 3.0 Unported
