1. BLM “sunglasses” Filter Box

2. Current layout: BLM crates CIBU units Rack BY02 / SR8 BIC crate ( UA83 ) User_Permits Maskable channel Unmaskable channel User_Permits

3. Proposed solution: 4 th crate BLM crates CIBU units Rack BY02 / SR8 BIC crate ( UA83 ) User_Permits Maskable UnMaskable channel User_Permits “BOX” 3 rd CIBU Maskable Rack BY03 / SR8 Injection pulse signal

4. Proposed solution (newer version): 4 th crate BLM crates CIBU units Rack BY02 / SR8 BIC crate ( UA83 ) User_Permits Maskable UnMaskable channel User_Permits Standard Beam Permit Permits UnMaskable Maskable Rack BY03 / SR8 1.Channels with injection signal beam permit signal dependence in new crate grouped 2.UnMaskable Beam Permit in 4 th crate set to true during injection (new VME card or implemented on present combiner card)

5. (basic) Functional Block Diagram Combiner card Output Time-out counter Output CIBU input TRUE FALSETRUE FALSETRUE FALSE FALSE state “masked”

6. Should have equivalent SIL level to both BLM & BIS systems Fail safe design Fixed time-out duration (no remote way to modify it) RF pulse period: Maximum repetition fixed by Hw Cross-check with the Energy value Remote monitoring of the input and output signals Etc.... Seems to be sensible to insert the “Filter box” into the BLM crate as an additional card (TBC) Thanks to VME-bus interface => Monitoring via dedicated FESA class. First brainstorming for the requirements:

7. The VME board (i.e. the “Filter Box”) will be studied, developed and tested within a closed collaboration between BE/BI/BL & TE/MPE/MI A specification is going to be produced If wished, study advancement could be regularly presented to this committee When proposal will be mature, it will be presented to MPP. If required, a (mini)Review could be organised What next?