The reason why the DET_MAIN node was stuck in SHUTTER_CHECK_CLOSED (see 47138), was because the node was waiting for the Vbias of the B1_PD2 photodiode to be engaged.But the B1_PD2 photodiode could not be rearmed any more since the last unlock at 06h33 utc this morning.
First we commented in DET_MAIN all the B1_PD2 checks, which allowed to make DET_MAIN happy and to lock the ITF in LN1.
Then we realized that by increasing the maximum current limit of the photodiode from 7.8 to 8.0 in the configuration file of SDB2_dbox_bench_LeftDown, we could rearm the photodiode.
This allowed us to restore Low Noise 3.
The checks involving B1_PD2 in DET_MAIN have been restored.