Help for Bunch Charge Feedback and Laser PowerIF BEAM IS LOST

MPS shutter in

Turn off all feedbacks (set enable to 0 for all)

Check: fancy phase control = 1, overall feedback gain, bunch length gain, L3 phase=0,

Enter default values for L0B, L1S amplitude, L1S Phase

Enter desired phase for L2

Wait 5 seconds

Enter amplitude for L2 (suggested amplitude is on right)

Enter amplitdue for L3 (suggested amplitude is on the right)

Check that L2 and L3 actuator strengths are on scale. If not, need to add or remove klystrons

Beam to 1Hz

Open MPS shutter

Turn on feedbacks in order, wait for each to stabilize

Restore rate

To change L2 phase

Close mps shutter

Disable BC2 peak current and energy feedbacks

Set desired phase in L2

Wait 5 seconds

Set suggested L2 amplitude into L2 amplitude control

Wait 5 seconds

If L2 actuator strength is out of range add or remove klystrons

Beam to 1Hz

Open MPS shutter.

Turn on feedbacks (Note, do not use peak current feedback at non-standard L2 phase)

For Overcompressed mode:

Turn off BC2 peak current feedback (set to 0)

Adjust L2 Chirp for desired overcompressed mode ~ -3500MeV

Turn on more tubes if out of range (probably need 1)

Set NEGATIVE of desired current into BC2 setpoint

Negative peak currrent setpoint sets for overcompressed

Turn on feedback

Hard limits:

Normally hard limits should be set to 1 = turn on hard limits

Set to 0 for on-crest operation or any time you do not want to limit control range

Note that with limits disabled feedback may run away.

Internal Limits:

In energy_feedback_new.m the software limits are set near line 255. These can be edited if desired, but use caution.

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