SAMS Stability Test
Purpose: Measure degradation of mirror array and what are the leading causes of it: Temperature, Motion, Wind, etc.
When to do: Currently, during cloudy nights but no threatening weather. This may change in the future as needed/requested.
Testing Modes: Static or Dynamic:
- Static: No motion at all. The structure and tracker stay in the same position during entire test.
- Dynamic: Commanded motion at some point. Either with a structure move or tracker motion or some combination.
Instructions:
- Record times at all steps. At the start and end of the test record all temps, louver state, wind speed and direction. You will be emailing a timeline to Hanshin when done. An example is below.
- Stack like normal and save reference and SCS ttp files. You can drop the HEFI measurements. Mark as ‘engineering’.
- In SCS, switch Move Authority to ‘None.’ Leave SAMS in closed loop (Operate mode).
- In Wavescope console, enter ‘Degrade X’ where X is the number of minutes you’d like to run the test without moving anything, between 10-30 minutes total. So, for a 10 minute test, you’d type ‘Degrade 10’. For an 18 minute test, ‘Degrade 18’. Run for however much you think you can get in addition to getting a 'Tighten-up' stack.
- If you’re doing a dynamic test, do not move until the Degrade command is done as it will create false measurements, if not crash the test. For example: For a test taking a total of at least 20 minutes, run ‘Degrade 10’, move, return to CCAS and realign, run ‘Degrade 10’ again.
Record the time of when you command the motion and where you moved to.
- When the test finishes, return SCS to SAMS authority and let the SAMS measurements go through then do a ‘tighten-up’ stack. Mark as engineering as well and save reference and SCS ttp files. You can take HEFI measurements if time allows. After finishing the tighten-up stack, restart the wavescope software before stacking again to reset values.
If you’re clouded out all night, taking multiple tests in different conditions/motions/temps/wind speeds would be great.
Email the timeline of steps and whatever motions made with the subject line “SAMS Stability Test (static or dynamic) taken ([date])” to Hanshin and cc Steven J and Cassie. Email example below.
Any questions, call Cassie: Home-403, Cell-828-755-7590
Timeline Email Example
To: lee@…
CC: janowiecki@…, ccrowe1@…
Subject: SAMS stability test (dynamic) 9/23
02:23-02:33; Degrade 10
02:33-02:40; Move to 180 az and back to CCAS
02:40-02:52; Degrade 10
02:52-03:02; Tighten up stack
Louvers: Fully open
Outside temp: 22.8→22.6
Internal temp: 23.4→33.3
Truss: 23.5→23.3
Average Wind: 14-9
Wind Direction: 182->178
