J. Kissel

E.J. identified recently that there were some filter modules which were requested to be ON, but had no filter in them -- see LHO:70179.

Between lock stretches, I reviewed the H1SUSZM1 and H1SUSZM2 filters,
Bank                              Filter Module          Bank Function
SUS-ZM1_M1_WD_OSEMAC_RMSLP_LL     FM6                    To low-pass the 0.1 to 10 Hz band-limited RMS signal 
                                                         of the top mass OSEMs. Only one filter is needed, and 
                                                         by convention that "10s" filter is in FM1
SUS-ZM2_M1_LOCK_L                 FM6                    The *infrastructure* is there generically for longitudinal 
                                                         ISC control for cavity locking, but ZM2 is only a steering
                                                         mirror, not a part of any cavity.
and found that these *must* have been turned on by mistake (and then blindly accepted in the SDF as such).

I've turned these FM6 filter requests OFF and accepted that "offness" in SDF to reduce confusion.
Note that both of these suspensions' channels live in the h1sussqzin model, so it's the same SDF file. 
Further, the h1sussqzin model is one of those models where the safe.snap and OBSERVE.snap are the same file,
so accepting the changes in the "safe.snap" from the SDF GUI interface accepts it in the OBSERVE.snap as well.

Importantly, having these filters mistakenly ON has no, zero, nada, zilch impact on anything. I merely turn them off for peace of mind and preservation of sanity.

In addition to turning off ZM2_M1_LOCK_L bank's FM6, I've also turned off the bank's input, since it's physically impossible for anything but zero to be fed into this bank -- the input is connected only to a "electrical ground" symbol in the front-end model, which is the advligo rts symbol for a fixed value of "0.0."