Helium lamp operation

Turning on the lamp

1. First check for wave guide connections and the setup in general.
2. Check water cooling is ON.
3. Open the helium line. If the line is not being used for long time, please purge the line.
4. Open the helium cylinder nob, open the control nob to pressure of about 1 bar.
5. Open the valve before the needle valve.
6. Open the needle valve slowly, and monitor the pressure. The FG1 in the VUV PCU should reach ~1 ✕ 10^-1 mbar. Roughly two full rotation in the needle valve, there is a blue mark.
7. Turn on the electronics of the helium lamp. Wait for few minutes.
8. If there is any red light/sign on the interlock, press the reset switch. It should clear all warnings/red lights.
9. Switch ON, and immediately OFF the HV ON/OFF switch to turn on the filament only. Wait for 1 minute.
10. Then switch ON the HV ON/OFF switch, and look in the viewport if there is peach color light (a color between orange and yellow). If not switch off the high voltage, and adjust the Helium pressure.
11. Check the reflection from wave guide. It should be close to zero. Otherwise, adjust the helium pressure.

Turning off the lamp

1. Switch off the High Voltage.
2. Press the reset button to switch off the filament, if not needed.
3. Close the helium needle valve.
4. Close the valve before needle valve.
5. Close the valves in the cylinder.
6. After switching off the filament, wait for about half an hour.
7. Once the filament temperature is below 40 °C, switch off the whole electronics.
8. Water flow can be closed, or left it running.