1. RPC HV&LV systems Introduction Detector description Requirements
I.N.F.N. Naples
Introduction
Detector description
Requirements
Systems description
Cables and connectors
Schedule
Summary
Conclusions
F. Loddo2, P. Paolucci1, D. Piccolo1, A. Ranieri2
1) I.N.F.N. of Naples, 2) I.N.F.N. of Bari
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

2. Pierluigi Paolucci - I.N.F.N. Naples
Introduction I
I.N.F.N. Naples
The CMS sub-detectors will be equipped with a large part of the HV and LV systems placed around the detector; in a not “easily accessible” area.
The RPC groups, in collaboration with the CAEN, have designed and tested an HV-LV prototype (SASY 2000) able to work in an hostile area. The system is based on the idea to split in two the HV and LV systems:
LOCAL: Central system (mainframes) placed in control room;
REMOTE: distribution system placed around/on the detector, consisting of a crate housing the HV and LV boards.
A natural evolution of the SASY2000 has been presented to CMS (May 03) by the CAEN company: EASY system.
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

3. Detector description I
I.N.F.N. Naples
There are 3 different kind of chambers with 2 or 3 bigaps and equipped with
6 or 12 or 18 Front-End Boards
RB2/3
Bigap
ALV1
DLV1
ALV2
DLV2
HV1
HV2
RB3 and RB4
ALV1
DLV1
ALV2
DLV2
HV1
HV2
Bigap
RB1 and RB2/2
Bigap
ALV1
DLV1
ALV2
DLV2
HV1
HV2
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Pierluigi Paolucci - I.N.F.N. Naples

4. Detector description II
I.N.F.N. Naples
RB1/RB2in
RPC chamber
Front-End
Bigap
Distrib. board
Bigap
ALV1
DLV1
ALV2
DLV2
ALV Analog Voltage = 7V Absorb. (6FEBs) = 0.42 A
DLV Digital Voltage = 7V Absorb. (6FEBs) = 0.9 A
I2C input
LV+I2C FEB out
LV in
Distributes analog and digital LV
It supplies LV power to 3 FEB chains
It supplies the I2C main line from LB
and one backup line from DT.
Total power/(ALV+DLV) ch.: 1.32 A * 7 V = 9.24 W
Expected Power  120 W/sector  7.2 kW/Barrel
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Pierluigi Paolucci - I.N.F.N. Naples

5. Pierluigi Paolucci - I.N.F.N. Naples
Barrel wheel overview
I.N.F.N. Naples 1 2 3 4 5 6 7 8
Muon racks 12 11 10 9
5 CMS wheels
12 sectors
balcony
12 sectors * 5 wheels = 60 sectors
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

6. HV-LV schema for a Barrel sector
I.N.F.N. Naples
78 FEBs = 13 ALV+13 DLV ch bi-gaps = 34 HV ch.
DT chamber
RB4
2+2 LV
6 FEBs / 2 bi-gaps
6 FEBs / 2 bi-gaps
4+4 HV
DT chamber
RB3
2+2 LV
6 FEBs / 2 bi-gaps
6 FEBs / 2 bi-gaps
4+4 HV
6+6+6 FEBs / 3 bi-gaps
6 LV
6 HV
RB2
DT chamber
4 LV
6+6 FEBs / 2 bi-gaps
4 HV
4 LV
6+6 FEBs / 2 bi-gaps
4 HV
RB1
DT chamber
4 LV
6+6 FEBs / 2 bi-gaps
4 HV
2 bi-gaps = 96 strips = 6 FEBs
LVD channel
HV channel
LVA channel
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

7. Pierluigi Paolucci - I.N.F.N. Naples
System requirements I
I.N.F.N. Naples
General requirements:
working in high magnetic field (up to Tesla);
working in an high radiation environment (5*1010 p/cm2 & 5*1011 n/cm2 & kRad);
local system in control room + distributed remote systems on the detector (at least for the LV);
redundancy of the control electronic devices (mP per board)
input voltage from the CMS AC/DC 48V power supply;
looking forward common CMS solutions in order to simplify the hardware and software development/maintenance of the systems
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

8. System requirements II
I.N.F.N. Naples
HV requirements:
12KV/1mA
Ripple < 100 mV pp at load per f < 20 MHz
Programmable voltage 0-12KV
Voltage step 10V
Voltage precision < 10V
V/I/Trip/Status control and monitoring
Error/Power leds
LV requirements:
7V/3A
Ripple < 10 mV pp at load per f < 20 MHz
Programmable voltage 0-8V
Voltage step 100 mV
Voltage precision 100 mV
V/I/Trip/Status control and monitoring
Individual ON/OFF
Error/Power leds
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Pierluigi Paolucci - I.N.F.N. Naples

9. System requirements III
I.N.F.N. Naples
Control and monitoring system requirements:
Common hardware and software (PVSS II) solution;
Detailed control/monitoring of the remote channels:
voltage/current and temperature
protections, errors and hard-reset for communication lost.
A second independent way to control them (telnet/ssh......)
Design requirements:
Possibility to easily increase the HV granularity;
Possibility to easily fix RPC problems:
disconnect high-current/sparking gap/bi-gaps;
modify the HV map in order to group bi-gaps with same working point;
Possibility to measure the RPC working-point in standalone.
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

10. Pierluigi Paolucci - I.N.F.N. Naples
HV-LV system design
I.N.F.N. Naples
Different HV and LV designs will be described in order to reduce the total cost preserving the system requirements, already analyzed and the trigger functionality:
1 HV/bigap 2 LV/6FEBs; FULL OPTION
1 HV/chamber 2 LV/chamber; CHAMBER OPTION
1 HV/station 2 LV/station; STATION OPTION
Then we will analyze two different solutions for both the HV and LV system based on the idea to have them on the detector or in control room.
HV in control room HV on the detector
LV in control room LV on the detector
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

11. HV-LV schema for FULL option
I.N.F.N. Naples
26 LV channels HV channels
Chambers have been designed with 2 gaps, of adjacent bi-gaps, connected to the same HV channel, in order to reduce the number of HV channels preserving the number of station available for the muon trigger
2+2 LV
6 FEBs / 2 bi-gaps
6 FEBs / 2 bi-gaps
2+2 HV
2+2 LV
6 FEBs / 2 bi-gaps
6 FEBs / 2 bi-gaps
2+2 HV
6 LV
6+6+6 FEBs / 3 bi-gaps
3 HV
4 LV
6+6 FEBs / 2 bi-gaps
2 HV
4 LV
6+6 FEBs / 2 bi-gaps
2 HV
4 LV
6+6 FEBs / 2 bi-gaps
2 HV
wheel 1 2 3 4 5
TOT
gaps
408
2040 HV
204
1020
FEBs
936
4680 LV
312
1560
FULL option
1 HV channel per 2-gaps
2 LV channels per 6-FEBs
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

12. HV-LV schema for CHAMBER option
I.N.F.N. Naples
16 LV channels HV channels
2+2 LV
6 FEBs / 2 bi-gaps
6 FEBs / 2 bi-gaps
1+1 HV
2+2 LV
6 FEBs / 2 bi-gaps
6 FEBs / 2 bi-gaps
1+1 HV
2 LV
6+6+6 FEBs / 3 bi-gaps
1 HV
Reduction of
2 LV
6+6 FEBs / 2 bi-gaps
1 HV
HV 1020  480 ch
LV 1560  960 ch
2 LV
6+6 FEBs / 2 bi-gaps
1 HV
2 LV
6+6 FEBs / 2 bi-gaps
1 HV
wheel 1 2 3 4 5
TOT
gaps
408
2040 HV 96
480
FEBs
936
4680 LV
192
960
CHAMBER option
1 HV channel per chamber
2 LV channels per chamber
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

13. HV-LV schema for STATION option
I.N.F.N. Naples
12 LV channels HV channels
2 LV
6 FEBs / 2 bi-gaps
6 FEBs / 2 bi-gaps
1 HV
2 LV
6 FEBs / 2 bi-gaps
6 FEBs / 2 bi-gaps
1 HV
2 LV
6+6+6 FEBs / 3 bi-gaps
1 HV
reduction
2 LV
6+6 FEBs / 2 bi-gaps
1 HV
HV 1020  360 ch
LV 1560  720 ch
2 LV
6+6 FEBs / 2 bi-gaps
1 HV
2 LV
6+6 FEBs / 2 bi-gaps
1 HV
wheel 1 2 3 4 5
TOT
gaps
408
2040 HV 72
360
FEBs
936
4680 LV
144
720
STATION option
1 HV channel per station
2 LV channels per station
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

14. More numbers about HV and LV
I.N.F.N. Naples
Looking at different solutions seems to be reasonable to have the following crate/board design:
HV board with 6 ch. (12 KV / 1 mA) 3 slots width;
LV board with 12 ch. (7 V / 3.2 A) 3 slots width;
6U standard Eurocard crate housing up to 6 HV/LV boards.
What do we have in the Station (final !) option ?:
1 HV board/sector  60 HV boards
1 LV board/sector  60 LV boards
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

15. Pierluigi Paolucci - I.N.F.N. Naples
SASY 2000 prototype
I.N.F.N. Naples
The HV-LV prototype 0 consists of: HV board (SA2001), 3 LV boards (SA2002) and 1 controller.
It has been split in three pieces, following a “logical separation” of the system, in order to study the functionality of every single piece and component.
The following tests has been performed on both the prototypes and will be repeated for the final boards:
Magnetic field test up to 7 KGauss (at CERN) (results shown by CAEN at CERN in May 2002)
Radiation test up to 10 LHC eq-years (at Louvain La Neuve) (results shown)
Test on the RPC to study the noise condition (to be performed at the test station in Bari);
High Stress Test to study the system under very hard conditions (under test in Napoli).
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

16. Detector and Control Room option
I.N.F.N. Naples
After having analyzed different solutions and after having discussed with the CMS collaboration and the I.N.F.N. committee we have decided to have the HV system in control room and the LV on the detector
What do Detector and Control Room mean ?
Detector: the LV crates are in the racks placed on the balconies (4 per wheel).
Control room: the HV crates are placed in the USC zone.
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

17. LV on the detector & HV in USC
I.N.F.N. Naples
Control Room
3 wires cable
about 6-15 mt long
max 12 watts
Total of 480 short HV cables HV
patch
panel
crate HV
patch
panel LV
crate 3 4 3 4
Multi-wire cable (16 couples)
about mt long
max 72 watts
Total of 60 long HV cables 2 5 1 6 12 7
8-12 wires cable
about 6-15 mt long
max 7 watts
Total of 720 LV cables 11 8 10 9 5 6
Detector
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

18. HV in Control Room 60 long cables (130 mt), double patch panels
I.N.F.N. Naples
Power consumption:
board = 72 W
crate = 430 W
Total 4.3 KW
60 long cables (130 mt), double patch panels
Easy operation on HV (bigap, chamber....)
9/20/2018

19. Pierluigi Paolucci - I.N.F.N. Naples
LV on the detector
I.N.F.N. Naples
4680 Front-End boards
720 LV channels
60 LV boards
20 crates (1 per balcony)
Power consumption:
board (12 ch.)  116 W
crate (3 boards.)  350 W
wheel (4 crates)  1.4 KW
Total  7.0 KW
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Pierluigi Paolucci - I.N.F.N. Naples

20. HV cable and connectors
I.N.F.N. Naples
The HV cable and connectors have been chosen and approved by CERN.
We already have half of the HV/LV connectors and some cable prototypes
2 high voltage pins to supply –12 kV
1 pin for signal return
insulating material
Polietilene HDPE (Eraclene Polimeri Europa (57%)
Masterbatch (GPO1246 Viba) (43%)
Metal cover connected to external chamber aluminum frame
ZAMA (UNI 3717 G-Zn A14 Cu1)
Suitable to sustain up to 15 kV
Cable characteristics:
According CERN safety instruction IS 23
Single conductor- = 0.16 mm
Conductor 20°C = 147 /Km
Core- = 3 mm
Screen wire-=0.2 mm (for 10 conductors)
Overall diameter = 8.4 mm (for 3 conductors)
Price: €/Km (for 10 Km)
Price: 24 Euro/couple pieces
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

21. LV connector and cable
I.N.F.N. Naples
The LV cable and connectors are under discussion
LV cable: 8 wires  outer diam. = 7.5 mm Price 1,00 Euro/m
12 wires  outer diam. = 8.5 mm Price 1,50 Euro/m
LV cable connector:
female 12 pins Molex Microfit-Fit 3,0 ( ) Price 3,49 Euro/5
female pins 20 AWG Molex Microfit-Fit 3,0 ( ) Price 10,37 Euro/100
LV RPC connector:
male 12 pins Molex Microfit-Fit 3,0 ( ) Price
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

22. LV and HV CAD cable design
I.N.F.N. Naples
Max LV/HV local cable lenght = 15 mt
Min LV/HV local cable lenght = 6 mt
Average lenght = 12 mt
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

23. Pierluigi Paolucci - I.N.F.N. Naples
Summary
I.N.F.N. Naples
We have designed a “reduced” HV and LV systems for budget limitation, keeping our requirements, consisting of:
HV (control room)
2040 gaps;
Power 4.3 KW
360/480 channels;
60/80 boards;
10/14 crates;
LV (balconies)
4680 FEBs;
Power 7.0 KW
720 channels;
60 boards;
20 crates;
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Pierluigi Paolucci - I.N.F.N. Naples

24. Pierluigi Paolucci - I.N.F.N. Naples
Schedule
I.N.F.N. Naples
Order cables and connectors in the 2003;
Design and build an HV patch panel prototype for Feb 2004;
Begin to install the LV cables and the short HV cables in the 2004
Begin to test cables and connections in the 2004;
Get the “final” I.N.F.N. OK for HV and LV in Sept 2003;
HV-LV tender (1 or 2 ??) before July 2004;
Test of the prototypes (B/rad/stress) asap in the 2004;
Board and crate production up to July 2005;
Test and install the boards-crates up to Sept 2005;
Commissioning the complete system in the second part of the 2005
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples

25. Pierluigi Paolucci - I.N.F.N. Naples
Conclusion
I.N.F.N. Naples
The HV and LV system for the barrel RPCs is well defined;
We are in the budget;
We already have money to order the cables;
We will get the money for the HV-LV hardware in the 2003;
Patch panel design/prototype will be ready for the Feb. 2004;
We hope to have a LV-HV boards prototype for July 2004;
If we can save money from the LV budged (as we hope) we will use them to upgrade the HV system to the chamber solution that is our goal.
9/20/2018
Pierluigi Paolucci - I.N.F.N. Naples