This afternoon the DET_MAIN node got stalled in SHUTTER_CHECK_CLOSED.

We suspect that the cause of the problem was a change in the electronic offset on the B1_PD3 photodiode (correlated with the detectiion lab humidity control test performed during the maintenance).

We adjusted the B1_PD3 offset by +0.0002 mW at 15h22 utc. Then after, performing a successful SHUTTER_CHECK_OPEN (since the shutter was actually opened), we performed a SHUTTER_CHECK_CLOSED to restore the standard conditions of DET_MAIN.