After moving the EE timing fanout from its direct connection to  the timing master over to the DTS fanout, we realised that if the DTS fanout unit was powered down this could cause H1 to go out of observation mode. This is because the Beckhoff SDF is monitoring the ACTIVE channels for all ports. If a client is powered down, the timing status would go RED. The only way to green it up, would be to reactivate the client or press the ACTIVE MEDM button, which would then take the IFO out of observation.

this morning I un-monitored the ACTIVE and SLAVE_NAME channels for port_8 on the master.

david.barker@zotws2: svn di h1sysecatc1plc1sdf_OBSERVE.snap

-H1:SYS-TIMING_C_MA_A_PORT_8_ACTIVE 1 Active 1
-H1:SYS-TIMING_C_MA_A_PORT_8_SLAVE_NAME 1 "Fanout Test Stand" 1
+H1:SYS-TIMING_C_MA_A_PORT_8_ACTIVE 1 Active 0
+H1:SYS-TIMING_C_MA_A_PORT_8_SLAVE_NAME 1 "Fanout Test Stand" 0