RPC’s HV-LV project Introduction HV and LV requirements I.N.F.N. Naples Introduction HV and LV requirements Solutions and costs USC and UXC space Conclusions SASY 2000 prototypes tests cables and connectors A. Boiano1, 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

Pierluigi Paolucci - I.N.F.N. Naples Introduction I I.N.F.N. Naples The RPCs sub-detectors of the LHC experiments will be for the first time equipped with a large part of the HV-LV system placed in a not “accessible” area. In CMS part of the systems will be placed around the detector; on the balconies. For this reason they will work in a very hard conditions for the high magnetic field and high radiation environment. 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples Introduction II I.N.F.N. Naples The starting idea for both ATLAS and CMS is to split in two the HV and LV systems for the RPC detector: LOCAL: Central system (mainframes) placed in control room; REMOTE: distribution system placed around the detector and consisting of a crate housing both the HV and LV boards. For both the systems we are working with the CMS sub-detectors looking forward for common solutions. A common project (SASY 2000) to design an HV-LV system is going on between the ATLAS and CMS RPC groups and the CAEN company. More and different solutions are under study by the CMS RPC group. 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

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 RB3 and RB4 ALV1 DLV1 ALV2 DLV2 HV1 HV2 Bigap ALV1,ALV2,ALV3 DLV1,DLV2,DLV3 Bigap RB2/3 RB1 and RB2/2 Bigap ALV1 DLV1 ALV2 DLV2 HV1 HV2 HV1 HV2 HV3 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

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 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

HV-LV schema for a Barrel sector I.N.F.N. Naples 78 FEBs = 13 ALV+13 DLV ch. 17 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 12 sectors * 5 wheels = 60 sectors 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples System requirements I I.N.F.N. Naples General requirements: system working in high magnetic field; system working in an high radiation environment; local system in control room + distributed remote systems on the detector; low voltage (48 Volts CMS common solution) running from the local to the remote system; HV floating channel (12KV–1mA); LV floating channel (7V ana/dig 0.42A/0.9A x 6 FEBs); 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

System requirements II 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. An independent way to control it (telnet/eternet....) 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

Pierluigi Paolucci - I.N.F.N. Naples HV-LV system design I.N.F.N. Naples Now we will analyze different HV and LV designs in order to reduce to cost of the system preserving the requirement 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 a local and remote system or to have the whole system in control room. HV in control room HV-CR HV on the detector HV-DET LV in control room LV-CR LV on the detector LV-DET 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

HV-LV schema for FULL option I.N.F.N. Naples 26 LV channels 17 HV channels RB4 2+2 LV 6 FEBs / 2 bi-gaps 6 FEBs / 2 bi-gaps 2+2 HV RB3 2+2 LV 6 FEBs / 2 bi-gaps 6 FEBs / 2 bi-gaps 2+2 HV 6+6+6 FEBs / 3 bi-gaps 6 LV 3 HV RB2 4 LV 6+6 FEBs / 2 bi-gaps 2 HV 4 LV 6+6 FEBs / 2 bi-gaps 2 HV RB1 4 LV 6+6 FEBs / 2 bi-gaps 2 HV LVD channel HV channel LVA channel FULL option for HV 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Numbers for the FULL option I.N.F.N. Naples The RPC 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 wheel 1 2 3 4 5 TOT gaps 408 2040 HV ch. 204 1020 front-end 936 4680 LV ch. 312 1560 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

HV-LV schema for CHAMBER option I.N.F.N. Naples 16 LV channels 8 HV channels RB4 2+2 LV 6 FEBs / 2 bi-gaps 6 FEBs / 2 bi-gaps 1+1 HV RB3 2+2 LV 6 FEBs / 2 bi-gaps 6 FEBs / 2 bi-gaps 1+1 HV 6+6+6 FEBs / 3 bi-gaps 2 LV 1 HV RB2 2 LV 6+6 FEBs / 2 bi-gaps 1 HV 2 LV 6+6 FEBs / 2 bi-gaps 1 HV RB1 2 LV 6+6 FEBs / 2 bi-gaps 1 HV LVD channel HV channel LVA channel CHAMBER option for HV 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Numbers for the CHAMBER option I.N.F.N. Naples The CHAMBER solution is based on: 1 HV channel per chamber 2 LV channels (ALV, DLV) per chamber going from 1020 to 480 HV ch. and from 1560 to 960 LV ch. wheel 1 2 3 4 5 TOT gaps 408 2040 HV ch. 96 480 front-end 936 4680 LV ch. 192 960 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

HV-LV schema for STATION option I.N.F.N. Naples 12 LV channels 6 HV channels RB4 2 LV 6 FEBs / 2 bi-gaps 6 FEBs / 2 bi-gaps 1 HV RB3 2 LV 6 FEBs / 2 bi-gaps 6 FEBs / 2 bi-gaps 1 HV 6+6+6 FEBs / 3 bi-gaps 2 LV 1 HV RB2 2 LV 6+6 FEBs / 2 bi-gaps 1 HV 2 LV 6+6 FEBs / 2 bi-gaps 1 HV RB1 2 LV 6+6 FEBs / 2 bi-gaps 1 HV LVD channel HV channel LVA channel STATION option for HV 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Numbers for the STATION option I.N.F.N. Naples The STATION solution is based on: 1 HV channel per station 2 LV channels (ALV, DLV) per station going from 1020 to 432 HV ch. and from 1560 to 720 LV ch. wheel 1 2 3 4 5 TOT gaps 408 2040 HV ch. 72 432 front-end 936 4680 LV ch. 144 720 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

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 option ?: 1 HV board/sector  60 HV boards 1 LV board/sector  60 LV boards The number of crates depends on where they will be dislocated and so are different in the Detector/Control Room solutions 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Detector and Control Room option I.N.F.N. Naples Looking at our requirements seems to be clear that should be more convenient to have the HV system in control room and the LV on the detector but in any case we have analyzed both the solutions in order to have a complete picture of the systems. What does mean Detector and Control Room Detector: in this case we can put the HV/LV crates on the racks placed on the balconies (4 per wheel) Control room: the crate are in the USC zone (150 meters far from the detector). 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples HV on the detector I.N.F.N. Naples 60-80 HV boards placed in 20 crates (1 per balcony) No easy access, no way to disconnect a bigap, difficult upgrade 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples HV in Control Room I.N.F.N. Naples 60 HV boards placed in 10 crates 60 long cables (130 mt), double patch panels Easy operation on HV (bigap, chamber....) 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples LV on the detector I.N.F.N. Naples 60 LV boards placed in 20 crates (1 per balcony) Power consumption: board (12 ch.)  116 W crate (3 boards.)  350 W wheel (4 crates)  1400W Total  7000 W 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

HV and LV cost estimation I.N.F.N. Naples The total costs of the systems are calculated using a spreadsheet having as inputs the following items: number of: connectors, cables, patch panels, boards, crates, controllers and mainframes cable length and installation costs cost of each of those items We have used the following prices (Euro): 3500 HV board, 2500 LV boards, 1500 crates, 3500 branch contr, 10K mainframe. HV control room HV on detector 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples HV and LV cost comment I.N.F.N. Naples The difference in price between the two solutions, after the HV and LV descoping, is of about 50K€ that is not enough to push forward the HV on the detector. Have the HV in Control Room means: Possibility to disconnect an high-current or sparking bigaps without switching of the other bigap; Increase the granularity when more HV boards will be available; Increase the number of HV channel when/if some station will drawn to much current. We hope to increase asap the number of HV boards from 60 to 80 in order to decoupling the RB3 and RB4 stations. 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples Space in UXC and USC I.N.F.N. Naples UXC space – DETECTOR option: HV per balcony  1 crate + 1 patch panel = 7 + 4 U LV per balcony  1 crate = 7 U TOTAL per balcony = 18 U UXC space – Control Room option: HV per balcony  1 patch panel = 4 U LV per balcony  1 crate = 7 U TOTAL per balcony = 11 U USC space – Control Room option: HV: 1 mainframe + 10 crates + 20 patch panel = 7 + 70 + 100 U 1 rack (35U)/wheel TOTAL = 177 U 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples Conclusions I.N.F.N. Naples We have designed a reduced HV and LV systems for budget limitation, keeping our requirements, consisting of: HV: from 1020 to 432  60 boards  20/10 crates LV: from 1560 to 720  60 boards  20 crates They cost now: 220K€ (LV) + 400/450 K€ (HV) We hope to upgrade the HV system as soon as possible at least to decoupling the RB3 and RB4 stations. The two option (Detector and Control Room) has a price difference of about 50K€. The HV in Control Room is a much better solution from any point of view. The system design will be discussed at I.N.F.N. next week and so we hope to have a final decision for that time. We need to have a prototype for the 2003 in order to put the order in the 2004. 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples SASY2000 project for RPC I I.N.F.N. Naples Electronic house 1 1 Branch controller From 1 to 16 4 4 All independent floating channels 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples SASY2000 project for RPC II I.N.F.N. Naples Detector region Electronic house 4 8 … 16 HV #1 HV #2 Branch controller #1 Complex ch. 1 256 Remote boards LV #1 LV #4 Branch controller #2 HV #1023 HV #1024 Complex ch. 512 … 256 LV #2047 LV #2048 Branch controller #16 What do we need ?? 26 ch * 12 sect * 5 wheels = 1560 LV 17 ch * 12 sect * 5 wheels = 1020 HV One mainframe is enough for the barrel The remote board has 2 Complex ch. each equipped with: 2 HV ch and 4 LV ch. 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

RPC HV-LV prototype SASY2000 I.N.F.N. Naples The HV-LV CAEN functional prototype consists of: 1 HV board, 3 LV board and 1 controller. The prototype has been split in three pieces, following the “logical separation” of the system, in order to study the functionality of every single piece and component. The final HV-LV board will have 2 complex channel each with 2 HV + 4 LV floating channels . It will be 6U high and 2 slots width. After the tests the factory will begin to design the final board integrating all these components in a single 6U – 2 slots boards. 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples Test performed I.N.F.N. Naples SASY 2000 prototype The HV-LV prototype 0 consists of: 1 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

Neutron radiation test I.N.F.N. Naples The SASY2000 HV-LV prototype has been tested twice (May-Aug 2002) at the Louvain La Neuve radiation facility. The total neutron fluence requests for 10 LHC years is about 1x1012 n/cm2 (note: in RE1/1 region) corresponding to 2 hours and 40 min with a beam at 1 mA at 70 cm SASY2000 In first session the system worked well for 30 min. corresponding to 1.8 • 1011 n/cm2 (a factor 6 higher than that expected on RB4!) We lost the communication with the prototype. CAEN reported a known loss of current gain due to irradiation on CNY17 opto-insulator used to enable the HV/LV channels. The prototype was irradiated for 80 min corresponding to 4.8*1011 n/cm2. On the second prototype (ATLAS one) the gain current loss was cured using a lower value biasing resistor. Was registered a few SE on the controller with loss of communication but the normal condition was restored after 1 s on power OFF/ON condition (it will be implemented by firmware an HOT RESET to recover the communication without interruption of remote power supply). After the irradiation the SASY2000 was tested outside, preserving its original functionality. (robustness of hardware) 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Magnetic field test setup Magnet: MNP24-1 at CERN Bldg. 168 B: up to 10 KGauss B around CMS: .44T Test condition: 0-7 KGauss Magnetic Field: up to 5 KGauss Test condition SA2001: VOUT = 8kV, Rload=12 M SA2002: VOUT0 = 4.7 V, VOUT1 = 5.0 V, IOUT0,1 = 1.9A from 0 a 5 KGauss: loss of efficiency 2% (// B) 0% ( B) (efficiency defined as =Pload/PDC-DC converter) (75%  73%) Future improvements: transformer oriented according  B  it will work reliably up to 8 KGauss 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

High Stress Test in Naples I I.N.F.N. Naples The High Stress Test system has been designed and developed by the group of Naples in order to make a very complete test of any HV-LV power supply. It consists of a test-box controlled by a PC running LabVIEW 6.1 At present the HST system is able to make: Long term test: A cycle of measurements (voltage and current) made using different resistive charge (from 1M to 10 G) to explore the whole range of the PS. Spark test: A cycle of spark at different voltage are generated in order to test the hardware/software behavior of the PS under this critical conditions. Calibration: independent measurement of the voltage and current (PS and test-box). The Trip-time, the rump-up and rump-down are also calibrated. 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

High Stress Test description I I.N.F.N. Naples The test-box consists of a custom rotating switch controlled by a step-to-step motor through a microcontroller (Microchip) . Each position of the switch corresponds to an electrical contact placed on a PCB and positioned on a circle at a distance of 22,5o each others. The motor needs 400 steps to make a complete turn corresponding to about 0.9o/step. 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

High Stress Test description II I.N.F.N. Naples Each position of the commutator is connected to: a different resistive charge (10G, 5G, 1G, 100M, 9M, 6); one of the four spark systems (10KV, 5KV, 2KV, short); OFF position. The spark system consists of two electrodes connected between the high voltage and the ground, placed at a fixed distance in order to generate sparks at a predetermined voltage. 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

High Stress Test description III I.N.F.N. Naples The micro-controller PIC 16F876-04 is used to: controls the motor through a custom board housing a “power driver” used to generate the phases needs to control the motor. drive the LCD monitor placed on the box and the manual control. drive the communication through a serial port RS232 used to connect it to a PC. control an internal ADC (10 bits) and drive a Programmable Gain Amplifier. It is used to measure the current provided by the PS at different full scale (1mA, 100 mA, 1mA). A C program has been written to control all the operations of the micro-controller. The program is stored in the internal flash memory. It also calculates the voltage from the measured current and takes in account the offset of each full scale. 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples The HST test box I.N.F.N. Naples rotating switch display RS232 port step motor manual control 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples HST LabVIEW display I.N.F.N. Naples output table Vmon Imon current 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples HV cable I.N.F.N. Naples The HV cable has been chosen and approved Suitable to sustain up to 15 kV Cable characteristics: According CERN safety instruction IS 23 Single conductor- = 0.16 mm Conductor resistance @ 20°C = 147 /Km Core- = 3 mm Screen wire-=0.2 mm (for 10 conductors) Overall diameter = 8.4 mm (for 3 conductors) Price: 1.050 €/Km (for 10 Km and 3 conductors cable) 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples HV connectors I I.N.F.N. Naples The HV connector has been chosen and approved Possibility to stack it up Electrical characteristics: Operating voltage: 15 kV Testing conditions: 20 kV 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%) (Conforming to TIS Rules) Metal cover connected to external chamber aluminum frame ZAMA (UNI 3717 G-Zn A14 Cu1) 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples HV connectors II I.N.F.N. Naples By CPE (www.cpeitalia.com) Price: 3 CHF/contact/10.000 pieces Schedule: The connector has passed CERN tests for chemical analysis Made electrical test performance (before and after radiation exposure) We are waiting for the final quotation before final order 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples

Pierluigi Paolucci - I.N.F.N. Naples LV connector and cable I.N.F.N. Naples 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 (43025-1200) Price 3,49 Euro/5 female pins 20 AWG Molex Microfit-Fit 3,0 (43030-0007) Price 10,37 Euro/100 LV RPC connector: male 12 pins Molex Microfit-Fit 3,0 (43020-1200) Price 9/20/2018 Pierluigi Paolucci - I.N.F.N. Naples