BIS 1 23 and SFP test loop The
BIS 1. 23 and SFP test loop The BIS 1. 23 and the SFP test loop - BIS 1. 23 project roadmap - The SFP introduction within the BIS - Status of the tests and results - Future plans Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop The BIS 1. 23 and the SFP test loop - BIS 1. 23 project roadmap - The SFP introduction within the BIS - Status of the tests and results - Future plans Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop The current BIS (in operation since 2006) has constantly shown a high level of reliability and availability. Today, the only identified concern is the optical part, which constitutes the weakest part of the present BIS V 1. A redesign of the BIS (BIS V 2), to improve the functionality (if required), the optical parts and also to address the components obsolescence, is foreseen and has to be deployed during LS 3 (2024 ->2025). Considering the resources within the MI section, the present work focusses on providing a reliable solution in order to operate the BIS V 1 up to the end of Run 3 (end 2023). The BIS 1. 23 addresses these issues without having the pretention to be a new version. At the same time the BIS 1. 23 allows to study new technologies which can possibly be retained after LS 3. Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop The current CIBO (optical daughterboard) in operation As the CIBO card is currently the “bottleneck” of the BIS, the aim is to replace this CIBO by another solution without other hardware modifications of the BIS: The CIBO is a home-made optical transceiver board realised with an Eled optical transmitter and a photodiode optical receiver. The drawbacks of the current CIBO are: • CIBO • Very low power margin • Typical output power -19 d. Bm • Maximum received sensitivity -28 d. Bm • LHC maximum fiber attenuation 6. 5 d. B (UA 27 to UJ 33) High gain drift versus temperature (no feedback compensation circuit for Eled) • • Christophe Martin TE-MPE-MI n: i g r ma B ! w d Ra 2. 5 - 0. 16 d. B / °C No monitoring of: • Real output power • Real receiver sensitivity • LHC fibers attenuation er w po n ? C i LH arg m 03/10/2017
BIS 1. 23 and SFP test loop The BIS 1. 23 and the SFP test loop - BIS 1. 23 project roadmap - The SFP introduction within the BIS - Status of the tests and results - Future plans Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop How to increase the BIS optical availability ? After some studies, the SFP (Small Form Pluggable) laser module seems to be a good candidate. The SFP advantages are: MRV SFP-GD-LX • Off-the-shelf modules • Industrial standard • Multiple suppliers • Choice of different characteristics • High power output (-15 d. Bm to -3 d. Bm) • Very low gain drift (internal temperature compensation) • Monitoring capability • Output power • Input power • …. . C t LH nen rs ma fibe g r pe er orin w po onit m Optikon SFP-LX & SFP-HX Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop Integration of the SFP within the BIS V 1. 0 The SFP validation tests have to be realistic and allow the implementation of the SFP within the BIS 1. 23. For this reason the SFP devices have been tested in the real LHC machine environment, mounted in place of the CIBO within the CIBM and CIBG on a test system in parallel to the operational system (see later). ü 100 % pin compatible ü 100% functionality compatible CIBO daughterboard SFP daughterboard Since for the CIBO daughter board connector there are no free pins available, the SFP monitoring registers available through an I 2 C protocol have been routed on the front of the SFP daughter board. Lemo 2 pin for I 2 C connection Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop First tests : Does the SFP work in DC mode ? BP True BP False The CIBO doesn’t work properly in DC mode (when the Beam Permit is False) , some oscillations appear False BIS frequency seen by the LBDS (LHC Beam Dumping System triggering system) with a CIBO (LS 1 MPS review) CIBM Local Permit BP False The SFP presents the same behaviors as the CIBO in DC mode : oscillations SFP output signal SFP input signal The SFP can’t work properly in DC mode SFP behaviour in DC mode not well defined Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop Second tests : introduction of the “False” state frequency To mitigate the DC level issue, a “False” state frequency has been introduced: • Beam Permit A “True” frequency = 9. 375 MHz (as today) • Beam Permit B “True”, frequency = 8. 375 MHz (as today) • Beam Permit A & B “False”, frequency = 921. 6 KHz (new frequency) CIBM Local Permit CIBG SFP input signal SFP dual frequencies test set-up True freq False freq CIBG SFP output signal CIBG SFP dual frequencies The transition from True to False is clean and without oscillations Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop Validation of the SFP & dual frequency in real situation We have the unique opportunity to validate this solution in real situation, in the LHC during two years (2017 – 2018) Ø We don’t touch the active BIS loops Ø We add new hardware: • 17 new BIC crates (Elma VME crate) • 2 new fibers links all around the LHC Ø We link the two BICs by the active BIC “local Permit” signals Ø Up to LS 2 (end 2018), the behavior of the active loops and the test loops will be constantly compared Ø Foresee to integrate a TSU (part of the LHC Beam Dumping triggering system) and CIBDS in the test loop for 2018 Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop SFP VME crate details VME Elma crate with: - MENA 20 (processor) - CIBSM (SFP I 2 C monitoring) - CIBG SFP - CIBM SFP - CIBPL (local permit receiver) CIBFMC modules (FMC board to read the SFP monitoring registers via I 2 C) CIBSM (SVEC board supplied by BE/CO + CIBFMC daughter board) Christophe Martin TE-MPE-MI CIBILP (Elma crate rear panel board intended to receive the local beam permit from the production BIC) 03/10/2017
BIS 1. 23 and SFP test loop The BIS 1. 23 and the SFP test loop - BIS 1. 23 project roadmap - The SFP introduction within the BIS - Status of the tests and results - Future plans Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop The different tests performed to validate the SFP solution Two distinct tests have to be performed to validate the SFP solution : 1) Validate the behaviour of the SFP loop compared to the LHC operational loop - This test is critical and concern the reliability (missed dump) and availability (spurious dump) 2) Validate the accuracy of the SFP monitoring values - This test is less critical, it affects only the availability To monitor the SFP a new GUI was deployed New LHC GUI: • External circle => Production BIC loop • Internal circle => SFP BIC loop Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop Test 1: behaviour of the SFP loop rather the LHC loop With the collaboration of the software team, an automatic tool is under development to monitor the discrepancies between the two Beam Permit loops. The comparison criteria are: 1) If there is a transition of the local permit on the SFP BIS, there should be the same transition on the operational BIS (and vice-versa) 2) If there is a transition of the Beam permit on the SFP BIS, there should be the same transition on the operational BIS (and vice-versa) In case of discrepancies an email is sent: For the time being the tool is under development, no statistics are available … But we are very confident, the manual comparison has shown for the time being no discrepancies between the both BIS loops Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop Test 2: the accuracy of the monitoring data (1/4) The most relevant information for the monitoring part is the SFP input and output power; the aim is to deduce the optical links power budget For the time being the CIBSM data cannot be exposed and logged within the SFP BIS GUI. A dedicated QT program can displayed these data by accessing directly the CIBFMC: TX and RX are used to calculate the fiber attenuation Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop Test 2: the accuracy of the monitoring data (2/4) Stable output power The next table is the SFP data for the CCR SFP BIS - The SFP automatic gain control adjust the laser diode current versus the temperature - The SFP output power is stable Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop Test 2: the accuracy of the monitoring data (3/4) On the next graphic, the 17 SFP BIS computed power margin data (for loop B) LHC optical links power margin => Received power – transmitted power ü Very stable measurements Same graphic for the A loop Since the installation (02/2017) we have a huge attenuation in Point 5. This problem has been resolved last month (wrong fibre connection) ü Although these 13 d. B of attenuation, the BIS loop could be closed; we have a very good power margin with the SFP … Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop Test 2: the accuracy of the monitoring data (4/4) If we compare the previous graph with the initial installation fibers attenuation values We have a systematical offset error This offset can have different sources - SFP devices measure the “Average” power, EN/EL ? - The SFP offset is not well calibrated Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop The BIS 1. 23 and the SFP test loop - BIS 1. 23 project roadmap - The SFP introduction within the BIS - Status of the tests and results - Future plans Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop BIS V 1. 23 The SFP devices have to be evaluated until LS 2 (end 2018) Ø Depending on the SFP tests results, the present CIBO module could be replaced by the SFP for the run 3 (2021 – 2023) on all the BIS loops BIS V 2 The SFP is a potential candidate to propagate the BIS signals all around the machines, but we have to decide: Ø If the Beam Permit loops will be transmitted through “frequencies” or “frames” Ø In case of frequency, if we use or not the “False” state frequency We have also to deal with the CIBF (long distance CIBU) that is using actually a CIBL board (laser version of the CIBO) and not a CIBO Ø The SFP could also replace the CIBL within the CIBF Christophe Martin TE-MPE-MI 03/10/2017
BIS 1. 23 and SFP test loop Thanks for your attention Christophe Martin TE-MPE-MI 03/10/2017
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