0. Safety

The RED light on the generator indicates that X-rays are ON (being generated)
The YELLOW lights on the "light tower" indicates shutter status - when lit the shutter is OPEN
The shutter cannot open while the enclosure doors are open - keeping the doors open largely guarantees you are safe from inadvertent irradiation - always keep the door open when you are inside the enclosure and only close them when you are ready for

1. Cryo system

> Dry air source, lN2 levels in dewar, program the cryo control box
Turn on the dry air unit and check that the flow gauge reads something like 15. (Dry air unit is the white box on the floor next to the generator)
Check the liquid nitrogen level as displayed on the fill control box. If it is < 6, refill the small dewar from the large one. Attach the large dewar (as necessary), verify that the pressure is < 25psi on the large dewar, then open the valve on the filler hose that connects to the large dewar. Flip the toggle switch from the fill controller from Close to Open. DO NOT LEAVE A FILLING DEWAR UNATTENDED AT ANY TIME. Fill the small dewar from the large one until the reading is 13. Do not overfill the dewar. If the large dewar is less than 1/4 full, take it to be refilled. Currently I have the fill control set to Auto, which does auto-fills for you but you still have to make sure there's enough nitrogen in the big dewar.
Turn on the cryo controller. Program the contoller so that you ramp from the current temperature to 100K at a rate of 120K/hour. It will take something like 1.5 hours to do that, so do this sooner rather than later. You should program the controller so that once it reaches 100K, it performs a Hold, and also program an End sequence in advance. Press Start to begin execution of the program. This will cool the system to 100K, keep it at 100K and then execute the end sequence when you hit Start again. See programming notes on the controller itself.

2. Optics Vacuum

The small silver-and-black vacuum pump that keeps the X-ray optics pumped down must be on at all times. You will damage the multilayer optic with out it. Just verify that it is working (it will be hot) and check that the manometer attached to the vacuum tube is reading its lowest value (all the way counter-clockwise, < 30 mmHg). The pump sits on the floor behind the generator to the right, on the enclosure wall side of the small cryo dewar.

2a. Helium

No longer needed

3. X-ray Generator

> Turn it up to full power slowly
The generator should be sitting at 20kV 10mA. It's full power setting is 50kV 100mA but you need to turn the power up slowly or it will trip out. Do it in several stages, increasing both the voltage (in 2kV steps) and current (in 4mA steps) at the same time, waiting at least 15 seconds between each step. Monitor the filament current (the ammeter on the front panel) which should NEVER EXCEED 1 AMP, and the voltage readout for the vacuum (LED on far right of front panel) which should remain relatively stable and not spike when you increase the power. The system should run at full power at less than 0.1 volt on the vacuum readout.

When steps 1-3 are completed, and the cryo system has cooled down completely to 100K, the machine is ready for use.

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Returning the IV++ System to the Idle State

1. X-ray Generator

> Turn down the power slowly
Return the generator to 20kV 10mA from full power in small steps (2kV; 4mA). Leave the X-rays running at 20kV 10mA.

2. Optics

> Do not change anything about the optics or the vacuum - just leave it as it is.

3. Cryo

> Press Start again to ramp the system up to 293K. Once it is warm, it will turn off the N2 flow by itself. When it reaches this point turn off controller, turn off dry air unit. DO NOT TURN THE DRY AIR UNIT OFF BEFORE THE SYSTEM IS AT ROOM TEMPERATURE.