J. Kissel, R. Bork, B. Abbott, D. Barker

In order to determine a good threshold for the new SUS Hardware Watchdog, we've shaken the ITMY chamber vigorously in various states of excitation. 
In summary, with 
- the HEPI and SUS user watchdogs disabled (actuator and inertial sensors set to un-tripably high values)
- ISI damping, SUS damping, and HEPI loops OFF (I just left the ISI tripped the whole time) and 
- driving HEPI at the limit of its DAC range (in Y, RX, and RZ), 
we shook the suspension (and ISI) enough that I would say "Wow, that's a *lot* of motion; it's giving me the willies. We should cut off SEI excitation after 10-20 minutes of this." 

This level of excitation produces roughly 110 [mV] RMS* from the RMS circuit of the SUS Hardware Watchdog. 
* The Hardware Watchdog currently does not expose the output RMS variables, either to analog or digital, so we've replicated what we believe is the SUS Hardware Watchdog's signal chain in the IOP model for the h1susb123's computer, based on the limited documentation available (namely Fig 4 of T1200306), and the DC gain of 31.2 [V/V] from the SUS Hardware Watchdog Chassis, measured on an identical setup in the H1 DAQ Test Stand (thanks Ben/Rolf!).

My figures of merit were 
- the ISI BLRMS Performance matrices, in which 
     - ST1 was solid red above the 0.3 [Hz] band in XYZ, 
     - ST1 was solid red in all frequency bands, and 
     - ST2 was solid red in all bands in all DOFs
- the QUAD M0 OSEM speed dials (the raw ADC input version), in which (for these particular DOFs of excitation from HEPI)
     - F1, F2, and F3 (which are the L, P, and Y sensors) were swinging quickly over *most* (not all) of their range (which is 0.7 [mm])
     - LF, RT, (which are the V and R sensors) showed signs of abnormally large movement, say 25% of their range
     - SD was moving minimally
- The DAC saturation counter screen for HEPI, which was showing several channels off-and-on saturating
- The ITMY Optical Lever, which was not swinging out of its range, but moving abnormally large, say 50% of its range



For future forensics, the rough times that I had this large excitation going was roughly between 
GPS: 1073411801 and 1073412182
UTC: Jan 10 2014 17:56:25 - Jan 10 2014 18:02:46
PST: Jan 10 2014 09:56:25 - Jan 10 2014 10:02:46 

Drive was 0.1 to 10 [Hz] "uniform" white noise, using three independent awggui sessions, driving channels
H1:HPI-ITMY_ISO_Y_EXC    100000 [cts]
H1:HPI-ITMY_ISO_RX_EXC   100000 [cts]
H1:HPI-ITMY_ISO_RZ_EXC   100000 [cts]

The QUAD, ISI, and HEPI survived admirably (as expected), and after the excitation was turned off, SUS and ISI damping loops were immediately functional again, and it quieted down to normal damped motion with ambient input motion from an unisolated chamber. All software watchdog values have been set back to their nominal values.