1 / 21

Low Voltage LB status

Low Voltage LB status. RPC detector and trigger group. Low Voltage Link Board status. After many failures in the link board system the RPC-Trigger community decided to investigate all the possible causes analyzing not only the LB system but also the LV system : A3016 boards MAO

cole
Download Presentation

Low Voltage LB status

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Low Voltage LB status RPC detector and trigger group

  2. Pigi Paolucci - CMS LV review

  3. Low Voltage Link Board status • After many failures in the link board system the RPC-Trigger community decided to investigate all the possible causes analyzing not only the LB system but also the LV system: • A3016 boards • MAO • LV and MAO power cut and power cycle • Power off and on of the link box • CAEN firmware Pigi Paolucci - CMS LV review

  4. A3016 behavior cutting the MAO 3Phase

  5. LV link board Schema SY1527 • MAO 48 service from BC • Output current = 15-18 A • EASY 3000 – Joint 48 Power & Service • Output power from A3016: • 2.5 Volts / 5.0 Amp • 3.5 Volts / 10.0 Amp 3-phase 48 service MAO 48 power 48 service EASY A3016 Link Box Pigi Paolucci - CMS LV review

  6. What powering OFF the MAO in the proper ways ? • Powering OFF the MAO via SY1527 or using the interlock placed on the front OK Pigi Paolucci - CMS LV review

  7. What powering OFF the EASY in a “bad” way ? • Powering OFF the EASY 3000 crate removing the power or service connector from the back OK Pigi Paolucci - CMS LV review

  8. What cutting the MAO 3-phase ? • Shutting-down the MAO cutting 3-phase • oscillation does not depend from the MAO load (from 4 A to 18 A) • sometimes 2 oscillations in few msec • oscillation disappear separating the 48 power from the 48 service • No other ways to reproduce it NOT OK Pigi Paolucci - CMS LV review

  9. What happen cutting MAO 3-phase ? • MAO goes OFF in 2 steps: from 48 to 22 V and a from 22 to 0 V • The A3016 channels go off when MAO voltage is around 22 V and this takes about 250-300 msec (fixed load on the MAO) • Around 22 V the boards begin to work not properly (Vcc goes from 12 V to 6 V) and generates oscillations on Vout. Vcc = 12 V Vmao = 22 V 6 V Pigi Paolucci - CMS LV review 7/6/10 Pigi Paolucci - INFN 9

  10. Mao behavior during 3Phase glitch

  11. At T0: • Turn off the 3-phase switch • MAO starts ramping down with a “dummy load” - NO status changing • After a while, it gives UNV status, but the channel keeps status ON. • At T1: • MAO ramps down with different slope (real load) • At T2: • MAO swiched ON (600 ms from T0). • Switching OFF-ON in <1sec, no IntFailstatus is generated by the MAO and the channel goes back to the 48V without any alarm acknowledge. Scope output 40 V MAO A3016 T0 T1 T2 Pigi Paolucci - CMS LV review

  12. What we have done ! Already implemented Solutions: • Introducing a big capacitor (33 mF) between the service and power line of the EASY • Improve the A3016 firmware • Modify the MAO firmware Long Term Solutions: • Designing a protection on the Link Box LV lines (see tomorrow meeting) • Separating the 48 service and power of the EASY ? OK Under test now Under test now Pigi Paolucci - CMS LV review

  13. A3016 firmwarerequirements • Couple of channels in tracking mode (ON/OFF/Trip at same time and with one command). • delay between the 2 channels must be less than 1 msec • Ramping up in stepping mode: • overshoot first steps < 10% of the setting voltage • overshoot of the last step must be < setting voltage • voltage must be always < setting voltage (no overshoot above max value) • Over-voltages are very dangerous for the LB. • no under-voltage dips are allowed after VCC2.5 gets above 2.0 V • no under-voltage dips are allowed after VCC3.3 gets above 1.2 V • total time to reach the setting voltages (3.5 V and 2.5 V) should be less than 60 msec Pigi Paolucci - CMS LV review

  14. MAO firmware requirements • The MAO behavior is case of glitch on the 3-phase line is potentially dangerous for the LV system. • Turn OFF the MAO when the Vmon < 43-40 Volts in about 100 msecand require an acknowledge afterwards to bring the channel back to ON. • In 100 msec firmware measures the voltage 5 times, should be enough. • After 100 msec the MAO voltage is around 35-38 V and it is enough to shut-down properly the A3016. Pigi Paolucci - CMS LV review

  15. New MOA firmware New MAO firmware MAO 43V 200 msec OFF – 38V Vcc Oscillations on both Vcc and Vout Vout old MAO firmware Pigi Paolucci - CMS LV review

  16. Rumping up - new A3016 firmware No overshot over the max voltage 3.5 V 2.5 V 50 msec 80 msec Pigi Paolucci - CMS LV review

  17. Overshot - new A3016 firmware Overshot < 10-15% voltage set Pigi Paolucci - CMS LV review

  18. Channels delay- new A3016 firmware Delay stable and < 2 msec (depends on the charge) 2 msec Pigi Paolucci - CMS LV review

  19. Results with C and diode service power 1.5 sec Pigi Paolucci - CMS LV review

  20. Results with C and diode No spikes or oscillations 48 V 600 msec 2.5 V Pigi Paolucci - CMS LV review

  21. Conclusions • Capacitor protection is working safe • New firmwaresare ready and under test at CAEN. • Next week will be tested at 904 • Both Capacitor boxes and firmwares have been payed by INFN (M&O-B 2010)  16 Keuro • Hardware protection of the Link Box is in any case necessary Pigi Paolucci - CMS LV review

More Related