Feedback Installation Status

Fast Feedback Installation PLAN

The Fast Feedback project will be rolling out installation of feedbacks on the new feedback IOCs in the following order (can be negotiated!):

• DONE: Injector Launch Feedback - 10Hz feedback on TS4 only (FB01:TR02)   lclshome | Feedback | IN20
• DONE: LTU Launch Feedback - 120Hz feedback using fast PAU controlled LTU magnets (FB03:TR01)    lclshome | Feedback | IN20
• in-Progress: Longitudinal Feedback - 120Hz feedback using fast PAU controlled RF stations (FB04:TR01)   lclshome | Feedback | Global
• DONE: Gun Launch Feedback - 10Hz feedback on TS4 only (FB01:TR01)       lclshome | Feedback | IN20
• DONE XCAV Launch Feedback - 10Hz feedback on TS4 only (FB01:TR03)      lclshome | Feedback | LI21
• DONE L2 Launch Feedback - 10Hz feedback on TS4 only (FB01:TR04)       lclshome | Feedback | LI21
• DONE: L3 Launch Feedback - 10Hz feedback on TS4 only (FB02:TR01), a channel access only feedback since BPMs are not on FNET
• DONE: LI28 Launch Feedback - 10Hz feedback on TS4 only (FB02:TR02) , a channel access only feedback since BPMs are not on FNET
• DONE: BSY Launch Feedback - 10Hz feedback on TS4 only (FB02:TR03)
• DONE: Undulator Launch Feedback - a 1Hz feedback on TS4 only (FB02:TR04) requires special code for energy changes
• DONE: Bunch Charge Feedback - a slow feedback on TS4 only (FB02:GN01) requires special code for waveplate control

NOTES for operators during commissioning phase

LTU and Longitudinal Feedbacks: The Update Act Refs and Restore Acts buttons will update/restore Actuator References and the actuator PAU Offsets, since these feedbacks use multiple patterns and offsets. The Zero Act Offsets button will set all actuator PAU offsets to zero.

MATLAB transverse feedbacks: You can return to a matlab feedback by clicking the 'Switch to Matlab Feedback" button on the feedback Detailed display. This runs a script to reconfigure alarms for the feedback. once the script is done you can turn on the matlab feedback.  The 'switch to Fast Feedback Test " button will let you switch back to the Fast Feedback.

MATLAB  6x6 Feedback: Switching between the matlab 6x6 (Joe's) and the 120Hz Fast Longitudinal is different. There is a 'Switch to Fast Longitudinal' button, and a 'Switch to Joe's 6x6' button. The following describes how to change manually:

When the Fast Longitudinal is running you can return to the matlab 6x6 feedback: by turning off the Fast Longitudinal, then go to the User Dev Displays | 6x6 feedback control, set the BC1 and BC2 Peak Current setpoints to the same as the Fast Longitudinal setpoint values, and then turn on each 6x6 loop individually (set to 1). 'fancy' phase control must be On (1) as well. 

To go from the matlab 6x6 to Fast Longitudinal you need to turn off the individual 6x6 loops (set to 0), but keep the "fancy" phase control ON (1), set the BC1 and BC2 peak current, and the DL2 Energy setpoints the same as the 6x6 setpoint values, then turn on the Fast Longitudinal.   The 'fancy' phase control must be ON for BOTH of these feedbacks.

Linac BPMs LI25 through LI30: These BPMs are not on FNET, so feedbacks in this region ( L3 and LI28) must remain on Channel Access until the switches here are upgraded. The L3 Feedback and LI28 Feedback must run at 10Hz or less.

ALL FEEDBACKS:  always turn OFF all fast feedbacks before rebooting a feedback hard IOC. The feedbacks must be OFF, not just disabled/compute mode. If the feedbacks are not OFF before a reboot, then you may encounter the problem described in the next item.

ALL FEEDBACKS: if a hard IOC has a power failure, it may not be able to connect to the feedback devices when it returns to operation. If you see the error message "cannot connect to <PV name>" on the feedback Detailed Display then you may need to switch to the old matlab feedback for awhile (try switching to the fast feedback again in an hour, or 4 hours, or one day later ??).