Because the H1:PSL-PMC-REF slider was adjusted to land on a value with much larger precision than the SDF file can deal with, it was in alarm out to the 10e-16 digit which could not be cleared with the ACCEPT button. The correct way to clear this bug is to write the epics slider to a smaller precision value (truncate it to the 10 e-8 or something digit). However, we are all the way back to Nom LOW Noise, and didn't want to risk this minute slider adjustment - SO, we set the channel to be NOT MONITORED until the next lock loss, when we should:
- Set this channel (H1:PSL-PMC-REF) to be MONITORED again in SDF
- Type in the SDF setpoint value (1.18615) into the slider value and check that it is no longer in error on SDF.
This was actually a temporary change we had to make to help the PMC lock that I had forgotten about. This setting can be reverted to its orginal value of 1.35V once the channel is set to be MONITORED again in the SDF.