Minutes of an interlock meeting held on 30th of September 2010

Agenda:

1. Proposal for a beam interlock system for Linac4 and PSB (B. Mikulec)
2. Related discussions (all)

1. Proposal for a beam interlock system for Linac4 and PSB

The presentation of B. Mikulec can be found at this link.

2. Related discussions

The following points have been discussed or came up after the meeting (page numbers refer to the presentation):

• Page 5: The BIS is asynchroneous. This means that the status of the BEAM_PERMIT can change at any time depending on the status of the connected user systems, also outside beam production. In such a case we do not want for example that the chopper reacts and pulses continuously. It has to be assured that for the BIC actions the required information on the cycle timing is included where needed (reminder: actions are foreseen on the H- source RF, pre-chopper, chopper, PSB RF, extraction kickers).
• Page 7: One additional input signal might be required giving information on the H- source status. R. Scrivens has been contacted to comment on this point.
• Page 8: As an additional safety, to avoid problems in case the timing modules would fail that translate the information of the destination from the telegram, the fifth destination 'L4DUMP' will be added. As a by-product this will also facilitate the reading of the Master BIC 'Choppers'.
• Page 9: The Linac4 RF input (OR of the status of the 19 klystrons) should be moved to a maskable BIC position (input number 9).
• Page 10: After the meeting it has been decided to use 2 BICs for the PSB injection permit. This will not only allow to add another system if needed, but will also leave more freedom to define correctly which input should be maskable or unmaskable. The output of one of these 2 BICs will be connected to an unmaskable input of the other BIC.
• Page 10: The BT line vacuum valves will be added to the BI and BR vacuum valve status (OR of all vacuum valves of BI, BR and BT).
• Page 10: The logic of the beam stopper should be changed as for a slave BIC all the entries have to be 1 (simple AND logic). Therefore we will rename the condition to 'Beamstopper OUT' and change the 0 to 1 on pages 7,8 and 10.
• The distribution list of the EDMS document will be extended.

The EDMS document will reflect the above-mentioned changes and will be released next week.

-- BettinaMikulec - 30-Sep-2010

• L4BeamInterlocks_Sept2010.pdf: Proposal for a Beam Interlock System for Linac4 and PSB