8-pack control system working group meeting

21 January 2002

In attendence: Chestnut, Frisch, Kim, Nelson, Rock, S Smith, Young

Notes by: J Nelson


(This look a lot like last week’s, but the contents are different.  I promise.  Unchanged contents are prefaced with (no change).)



-Progress from Kukhee: PMAX and PMIN work now.  It’s another week or two of work until the ADC channels are fully implemented.

-Kukhee reported the database displays for PWR ADC channels are done.

-Janice figured out an old action item from Steph concerning the load out versus hybrid out naming convention was moot.  Steph was confused.  We have the right number of PWR PVs for the hardware.

-Janice reported she added diagnostic plot buttons for the powers to the klystron panel.  The plot can also be selected from the pwr database display (>db button).



-No new progress.  They’re done we think.

-Steve informed us that we do indeed have enough DACs for 4 klystrons.


DAC/ADC Issues

-Phase wraparound was discussed.  It was decided that one could input any number but then it’d be given the equivalent value between +/- 180.

-Steve said that no, we don’t need a gold phase for each klystron/time step.

-The trickle down of the SLED variables was discussed.  This was specified at a previous meeting (numbers on SLED panel need to trickle down to I/Q and A/P PVs).  For processing, we might want this feature functional sooner rather than later. 

-After the meeting, Janice and Steve discussed the trickle down of the variables on the power distribution panel as well.  There are 4 PVs there called Klystron Sled-in phases.  These need to trickle down to the phase DACs as well.  This phase is to be added to the channel phase angle (IQ calib panel) and to the timestep phase before going out to the DAC.



-Andrew emailed a channel assignment for the DIO.  Joe pointed out we’ll need a spare out channel to give a TTL pulse to reset his kludged interlock until the “real” interlocks are working.

-We discussed what the mux panel select panel should look like.  After the meeting, Steve and Janice discovered it already exists on the IQA module panels.

-On IPL, the mux select for all four IQAs should come up as channel 0.

-Andrew said he’d fix the slow rise time problem

-(no change) The following item was deferred for a few weeks:

LLRF + NLCTA Ops need to sort out what the LLRF enable and the mod off buttons do


SCP Configs

-Janice reported that there are now config regions for all 4 klystrons (not just the two) and gold configs for all of the 8-pack epics regions.

-Steve requested that the calibration numbers for each klystron be removed from the individual klystron config regions and put into their own special region.  Janice will work on that this week.



-Ron and Kukhee reported they think all the necessary waveforms are in the database.  On Wednesday, Janice did a check and found 36 that didn’t exist yet and sent the list to Ron and Kukhee.

-(no change) Joe has one of the modules otherwise they’re all out in the crate

-(no change) We deferred the following: longer term issue: what to do if reading out an SIS when a fault occurs?

-(no change) Right now the SISes are paused and read out with a user request only.  A read when a fault happens will also be added to this.




-Janice sent a list of waveforms to be archived to Bob et al

-(no change) SWE plans to implement the following two features requested by LLRF (Joe’s email):

have waveforms archived on (1) every trip and (2) when a save is requested by the user

-(no change) Later SWE will work with Joe on his other two requests: archive every few minutes and when a change occurs in a selected set of values in EPICS (a pseudo-trip if you will)

Other analogs

-(no change) Lee Ann got the list from Judy and told Janice the values were being saved to Oracle

-(no change) Bob will switchover NLCTA/8-pack to Oracle sometime this week



-we think we’re done.



-Each IQA channel has 6 or 7 calibration numbers that are module dependent.  Gain/offset I,Q, quadrature angle and overall phase.  These numbers are used to change the SIS waveforms from I/Q to A/P.  These numbers will go on the IQA module panel. 

-Steve will provide the equations for this calculation

-These 6 (or 7) numbers x 8 channels x 4 IQAs need to be archived at a fault.  The panel interface could just be one table for each IQA with 8 rows for the 8 channels and 6 columns with the calibration variables.


Processing algorithm

-(no change) Ron and Kukhee reported that the work is ongoing


Peak Power Meter (PPM)

-The names were chosen as CHAN1-4 plus an extra string that will be saved to errlog when it gets changed.  This string will ideally hold some descriptive text about what physical signal is being input to that PPM channel.

-We need database for the usual PPM PVs (NLCTA list) plus a waveform for each channel.  Janice will send this list to Ron.

-(no change) Tonee will tweak the labview program to send the waveform to epics once we have names

-(no change) Tonee and Janice will set up the necessary hardware in ESB (Enet box, cables, etc)

-Janice had made some panels but with these new specifications will change them. 



-(no change) We’re currently waiting for Dick’s setup to settle down then we’ll do one more iteration of getting list, changing database, changing panels, programming the dcm, changing alarm handler and archiver stuff as needed



-Judy will make sure crate profile on web is up to date for next week

-Janice will continue to work with Bob Fuller for a dead man switch for epics (Bob will be invited next to our meeting next week).

-Janice will work with NLCTA Ops to sort out if we need to read out the bucking coil current different from other analogs (next week)

-(no change) we deferred the following:

-public/private matlab issues to be resolved at a later date

-LLRF needs to decide what the reset button does.

-Steve requested that the digits after the decimal points on the phase panel go away.