Perform an Air0 from terminal

How to perform an air zero from terminal on a series 5 refractometer.

The steps below are for performing an air0 from the firmware (backend) when the status bar displays there is something on the prism and all other possible causes have been eliminated as a possible cause.

1. Clean and cover the prism
2. Connect a keyboard to the instrument
3. Press and hold the Alt key then the F4 key
   1. This will open a window
4. Select Terminal
5. On the keyboard and within 3 seconds, type the following sequence. You may have to try this a couple of times if you don’t get it the first time.
   1. Esc, Esc, Ctrl+C, 1,2,3,g (remember to hold down the Ctrl key and press the C key then let go of the Ctrl key)
6. The terminal window should open displaying CMD> with a blinking black box. If you only see the black box, the key strokes of step 4 has to be performed.
7. At the terminal window type air0 (air and the number zero with no space). It may not appears that anything happened but give it about 30 seconds
8. Type Exit
9. Press the red X on the upper right corner to close the terminal window
10. Select Back to Refractometer
11. Confirm if the quality status bar resets and the instrument is working normally.