RPC HV-LV project Introduction System requirements and description I.N.F.N. Naples Introduction System requirements and description SASY-2000 project Prototype tests Alfonso Boiano1, Flavio Loddo2, Pierluigi Paolucci1, Antonio Ranieri2 1) I.N.F.N. of Naples, 2) I.N.F.N. of Bari 17-Apr-1917-Apr-19 Riunione Referee Roma - 6 Sttembre 2002

Riunione Referee Roma - 6 Sttembre 2002 Introduction I.N.F.N. Naples The idea of the HV-LV system for the RPC detector of the LHC experiments is to split the system in two: LOCAL: SY1527 mainframes placed in control room and a 48 Volts High Power Source; REMOTE: distribution system placed in the UXC zone around the detector. It consists of a 6U custom crate housing 2 independent controllers and up to 8 distribution board equipped with 4 HV + 8 LV floating channels. The system will work in very hard conditions due to the high magnetic field and high radiation environment. A common project (SASY 2000) to realize this system is going on between the I.N.F.N. and the CAEN company. 17-Apr-1917-Apr-19 Riunione Referee Roma - 6 Sttembre 2002

requirements and system description I.N.F.N. Naples 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) running from the local to the remote system; floating HV (12KV–1mA) and LV (7V–0.42A (ana.) and 7V–0.9A(dig.)) channels (noise reduction). wheel 1 2 3 4 5 TOT gaps 408 2040 HV ch. 204 1020 front-end 936 4680 LV ch. 312 1560 having chosen 2 gaps per HV channel and 6 FEBs per LV channel 17-Apr-1917-Apr-19 Riunione Referee Roma - 6 Sttembre 2002

I.N.F.N.-CAEN SASY2000 project I.N.F.N. Naples Detector region Control Room 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 48 Volts High Power Source The remote board has 2 Complex ch. each equipped with: 2 HV ch and 4 LV ch. 17-Apr-1917-Apr-19 Riunione Referee Roma - 6 Sttembre 2002

Riunione Referee Roma - 6 Sttembre 2002 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) (see attached results shown by CAEN @ 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 (to be performed in Napoli). 17-Apr-1917-Apr-19 Riunione Referee Roma - 6 Sttembre 2002

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 optoinsulator 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) 17-Apr-1917-Apr-19 Riunione Referee Roma - 6 Sttembre 2002

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 17-Apr-1917-Apr-19 Riunione Referee Roma - 6 Sttembre 2002

Magnetic field tolerance 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 Da 0 a 5 kGauss: loss of efficiency 2% (=Pload/PDC-DC converter) (75%  73%) Future improvements: transformer oriented according  B  it will work reliably up to 8 kGauss 17-Apr-1917-Apr-19 Riunione Referee Roma - 6 Sttembre 2002

High Stress Test in Naples I.N.F.N. Naples The High Stress Test is based on a large number of cycles of the following tests: Low current (1 mA) test at “working” voltage (10 KV); Medium range current scan (from 10 to 300 mA) at “working” voltage: High current (1 mA) test at “working” voltage (10 KV); Over-current and Trip test (I > 1 mA); Maximum voltage test (12 KV) at different absorbed currents; Discharge and short circuit test made with two pins at different distances; Imon, Vmon calibration test made with an independent volt-meter. Different HV resistors A PC running LabVIEW will be used to control the system and to analyze the data. Final HV-LV cable/connector will be used. 17-Apr-1917-Apr-19 Riunione Referee Roma - 6 Sttembre 2002

HV-LV architecture for a barrel sector I.N.F.N. Naples 26 LV channels 4 Remote Boards 17 HV channels RB4 4 LV 2 bi-gaps 2 bi-gaps 4 HV ch 1 RB 2 RB RB3 2 bi-gaps 2 bi-gaps 4 HV ch 4 LV 3 bi-gaps 6 LV ch 3 HV ch RB2 1 RB 1 RB 4 LV ch 2 bi-gaps 2 HV ch 4 LV ch 2 bi-gaps 2 HV ch RB1 1 RB 1 RB 4 LV ch 2 bi-gaps 2 HV ch 2 bigaps = 96 strips = 6 febs LVD channel HV channel LVA channel RB = remote board 26 ch * 12 sect * 5 wheels = 1560 LV 17 ch * 12 sect * 5 wheels = 1020 HV 4 remote boards * 12 sect * 5 wheels = 240 RB 17-Apr-1917-Apr-19 Riunione Referee Roma - 6 Sttembre 2002

Barrel cables routing LV HV 26 LV ch/cable + 17 HV ch/cable per sector I.N.F.N. Naples 26 LV ch/cable + 17 HV ch/cable per sector LV-HV 1 2 LV-HV LV-HV 3 4 LV-HV Sector -4 Sector -5 LV-HV Muon racks 2 RPC HV-LV crates Sector –6 LV HV 26 LV ch/cable 26 LV 17 HV LV-HV 5 6 LV-HV 7 8 Elect. house 17 HV 26 LV 17 HV ch/cable LV 48 remote boards/wheel  240 Remote Board 1 crates/rack  8 crates/wheel  40 crates 17-Apr-1917-Apr-19 26 ch * 12 sect * 5 wheels = 1560 LV 17 ch * 12 sect * 5 wheels = 1020 HV HV