Minutes and Action Tasks from Feb 20, 2020 Electronics and Readout Integration Meeting
- Attendees: Linda, Anne, Geoff, Ting, Adi, Francesco, Min Jeong and Sasha.
- News item:
- Decommissioning work is progressing well. ESH issue with lead strip removal is mostly solved. Electronics disassembly got a great start thanks to Clarence, Anne, Howard and Steve. We are planing to re-install Minerva modules at downstream end MINOS hall this summer for DAQ developed. Light and charge readout boards will be borrowed from BERN next time for the DAQ test.
- Schedule of 2x2 test at BERN slipped quite bit due to delay of LArPix chip production. We are now expecting to have the detector delivered to Fermilab late Fall 2020. This gives us more time for the integration design. There are still quite of tasks ahead of us though.
- Linda summarized the work done at BERN on grounding isolation and monitoring.
- A lot of details in her slides posted in the meeting indico and I only list action tasks here.
- The BERN group will have a safety review of the new grounding isolation scheme (p4 in the slides) in couple of weeks. Francesco will report back on the review result.
- The saturable inductor needs to be repacked to fit the space limitation at BERN.
- The plan is to get the inductor sent back to Fermilab with 2x2 detector.
- Linda and Francesco propose to install an impedance monitor at BERN. The monitor was already designed. Linda is to estimate labor and M&S cost. We will find a way to fund the project.
- For cryostat electrical isolation, 5cm thick of POM is inserted between the cryostat support legs and concrete floor. Francesco is to provide detail info of this -- sharp, size etc. so Linda can carry out her calculation on capacitance. We need similar isolation in MINOS layout.
- Networking discussion
- We collected info of networking setup for various subsystems -- detail in slides posted
- Many of the subsystem has front-end boards connected to Ethernet switch directly with CAT5/6 copper cables (i.e. charge readout) or optical fiber cables (i.e. light readout).
- We need to pay attention to the grounding isolation from front-end (on detector ground) and DAQ (on building ground).
- We used to separate the two groundings at the input to network server. Connections to the server from front-end boards either uses optical fiber or copper-to-fiber converter.
- Charge readout system for 2x2 uses 16 ArtyZ7 cards. We need 16 cooper-to-fiber converters to following old grounding isolation rules. This scheme has difficulties when the number of cards used are large like in near detector argonCube case.
- A new proposal is to separate grounding at the DAQ server input instead at network switch input. This works fine for both light and charge readout systems.
- Linda agrees the proposal. Everyone in the meeting agree too.
- Light readout system propose to use 10G network switch with fiber optic links to ADC cards. This is fine. But there is a Ethernet connection from "control unit" to PC directly. This breaks grounding separation rules. Sasha and DUBNA group need to look this in detail and report back to integration meeting.
- Geoff point out we should also consider data rate requirement when designing network system. For example, if each ADC pumps out data at rate of 10gbps, do we need the link between switch and DAQ server to be more than the sum of all the ADCs like 70gbps for a 7 ADCs readout? We need the DUBNA expert provides more detail on this. Same goes to the ArtZ7 cards of charge readout.
- Geoff will use the info collected and write a network requirement documentation for 2x2 test in MINOS. He will need to get answers on the data rates of subsystems and also DAQ server requirement.
- With the network requirement, we will discuss with Fermilab network group for implementation.
- Other things to consider are triggering scheme, event builder designs, database (detector configuration for example) and running conditions (allowed downtime etc,)
- We discuss a little bit on LV power supply controls, HV drift and MINERvA DAQ.
- We asks Francesco to report back BERN's choice on HV PS. In particular, we like to know the AC requirement for the PS and also the control scheme. For example Spellmam-150 takes 220V +/- 10%. MINOS hall has 208V outlet. Is this OK?
- We will look other experiments on LV power supply control experiences.
- We need to look more on event builder scheme to combine MINERvA and argonCube2x2 data segments. In particular we need to flush out details of time stamp and how to stitch data segments together. A lot of more to think about.
- AOB
- Francesco propose to change the start time to 10:30CST so people can attend the Analysis meeting on LAr ND.
- If you have objection to the starting time change, please let Ting know ASAP. Otherwise, we will do 10:30 -- 12:00 CST
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