Experimental Physics and
Industrial Control System

"Shen, Guobao via Tech-talk" <tech-talk at aps.anl.gov> · Thu, 20 Feb 2020 14:40:50 +0000

> the target delay must always be set so that it is greater than the physical delay, including internal delays. Otherwise some events will be missed

That's interesting and good to know.
It seems a firmware issue. Did you get any response from Jukka?

> We are starting the commissioning phase soon so we will have better results.

Would love to know your experience.

Thanks,
Guobao

On 2/20/20, 2:40 AM, "Javier Cereijo García" <javier.cereijogarcia at ess.eu> wrote:

    Hi all,

    Yes, here at ESS we have done some tests in the lab in the past, 
    although they were quite simple. I can share what we have learnt. These 
    tests were done using mTCA-EVR-300 and mTCA-EVM-300, not VME.

    The first feeling is that everything works as expected, and changing the 
    target delay works smoothly, as well as changing the length of the 
    optical fiber. There is one thing though that seems strange to me, and 
    it is that the target delay must always be set so that it is greater 
    than the physical delay, including internal delays. Otherwise some 
    events will be missed. Even when using a 230-series EVG with the delay 
    compensation disabled on the EVR side the target delay needs to be set 
    correctly.

    We didn't perform any complex jitter test, although monitoring the "DC 
    lock" shows that it gets unlocked from time to time, usually recovering 
    quickly. We didn't worry too much at that moment, the measured delay 
    wasn't changing that quickly, I think that the lock monitor is quite 
    sensitive. I can't recall from the top of my head if we were using the 
    EVM's fractional synthesizer or an external RF source, so this may 
    easily disappear in a more stable environment.

    We are starting the commissioning phase soon so we will have better results.

    Best regards,

    Javier

    On 19/02/2020 18:17, Michael Davidsaver wrote:
    > On 2/18/20 10:43 AM, Shen, Guobao via Tech-talk wrote:
    >> Hi all,
    >>
    >> Is there anyone who has been using MRF EVM-300 delay compensation function for any purpose, in the lab, test stand, real machine, etc?
    > ESS did some testing as well.
    >
    >> If yes, would you mind to share us your experience?
    > As I recall, it worked well on a test stand.  My personal knowledge ends there.
    >
    >
    >> Thanks,
    >>
    >> Guobao
    >>
    >>   
    >>
    >> --------
    >>
    >> Guobao Shen
    >>
    >> gshen at anl.gov <mailto:gshen at anl.gov>
    >>
    >> Controls Group Leader
    >>
    >> Advanced Photon Source
    >>
    >> Argonne National Laboratory
    >>
    >> 9700 S. Cass Avenue, Lemont, IL 60439
    >>
    >>   
    >>
    >>   
    >>
    -- 
    Javier Cereijo García

    Embedded System Engineer
    HW&I group, ICS division
    European Spallation Source ERIC

    Mobile: +46 (0)72 179 23 34
    E-mail: javier.cereijogarcia at ess.eu

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System