Introduction · Web viewIn addition, there are two filter boxes mounted on each CE flange, plus a system of heaters to prevent condensation on the flanges, and a system of fans to

TPC Electronics Cable and Fibre Plant on the Top of the Cryostat

Document identifier: Created: June 23rd, 2020 Page: 1 of 20

EDMS id 2xxxxxxModified: June 23rd, 2020, 2020 Rev. No.: 1

TPC Electronics Cable and Fibre Plant on the Top of the Cryostat

This document describes the naming convention for the DUNE Single Phase Far Detector.

https://edms.cern.ch/document/2xxxxxx/1

Prepared by:

M. Verzocchi (FNAL)

Checked by:

A. Person (institution)

To be approved by:

B. Person (institution)

Distribution List

TABLE OF CONTENTS

1

Project Document No:2xxxxxx Page:2 of 10

1 Introduction2 Naming convention for the APAs, corresponding spool pieces and flanges3 Cable connections on the CE flanges4 Fiber connections on the optical patch panel on the PD minirack5 Racks on the detector mezzanine used by the TPC electronics consortium6 Cable connections on the detector mezzanine7 Fiber connections on the cryogenic mezzanine and the DAQ room

Revision Date Author History of changes1.0 23.6.2020 MV First version

2

1


1 IntroductionThis document describes the cable and fibre plant used to connect the detector elements of the TPC

electronics consortium for the first DUNE Single Phase Far Detector module, to be installed in the north cavern at the Sanford Underground Research Facility (SURF). It also includes a brief summary of the naming convention to be used for these detector elements. The layout of the LBNF caverns at SURF is shown in Figure 1 (taken from EDMS, this is version 6 of the integrated LBNF/DUNE model). In this layout the neutrino beam comes from the right (east) and is directed toward the left (west). The first DUNE Single Phase Far Detector module is installed on the east end of the north cavern. The detector racks installed on the mezzanine are on the north side of the cavern. The technical cryostat opening (TCO) used to insert the anode plane assemblies (APAs) into the cryostat is on the west side of the cryostat.

Figure 1: Layout of the LBNF facility at SURF with the first Single Phase Far Detector module in the north cavern.

2 Naming convention for the APAs, corresponding spool pieces and flangesThere are 150 APAs installed inside the cryostat, arranged in three arrays of 50 APAs each. One array

is close to the north side of the cryostat, another one is close to the south detector mezzanine, while the third one is the middle of the cryostat (central). Each array of APAs is made of 25 doublets, with two APAs stacked vertically. Each APA doublet is served by a single cryostat penetration. A cross-shaped spool piece with three flanges is mounted on top of each cryostat penetration. One of the flanges is used for the connection of the cables for the photon detectors (PD) and for the resistance temperature detectors (RTDs) mounted on the two APAs, while the two other flanges are used for the cables used to read out the APA wires and for the cables providing the bias voltage to the APAs and to the field cage (FC) termination electrodes, as well as for the cables used to monitor the ground plane currents. We refer to

3

https://edms.cern.ch/document/2053096/6

1


these flanges as the PD flange and the two CE (Cold Electronics) flanges. The PD flange is entirely passive (i.e. it contains only connectors), while on each CE flanges a warm interface electronics crate (WIEC) is mounted. Each WIEC contains one power and timing card (PTC) as well as five warm interface boards (WIBs). In addition, there are two filter boxes mounted on each CE flange, plus a system of heaters to prevent condensation on the flanges, and a system of fans to provide cooling to the WIBs and PTC. The PD and CE flanges, and the boards mounted inside the WIEC (WIBs and PTC) serve as the starting point for the cables and fibers that run outside the cryostat.

Figure 2 shows the top of the cryostat (the mezzanine with the cryogenic equipment and the data acquisition room is not shown in this picture). The three arrays of 25 cryostat penetrations each are visible in the picture. The inset shows (in purple) one of the cryostat penetration with the PD mini-rack nearby. The PD mini-racks are used to house some of the electronics for the readout of the photon detectors, as well as some patch panels for optical fibers. The relative position of the PD mini-rack and of the spool piece differs from one array of cryostat penetrations to the next.

Figure 2: view of the first Single Phase Far Detector module. The 75 cryostat penetrations for the TPC electronics are visible in this image (the inlet contains a zoom in the region of one penetration, with the cross shaped spool piece visible in purple). Also visible is the detector mezzanine with the racks containing the readout electronics for the detector. The second mezzanine with the cryogenic equipment and the DAQ room is not shown.

Figure 3 shows a cross section of the cryostat with the three arrays of 25 APA doublets. Between each array of APAs, there is an array of cathode plane assemblies (CPAs): there are therefore two CPA arrays, the south one (between the south and central APA arrays) and the north one (between the central and north APA arrays). This arrangement gives four distinct drift volume, which we number in the following way:

Drift volume A, between the north CPA array and the north APA array; Drift volume B, between the central APA array and the north CPA array;

4

1


Drift volume C, between the south CPA array and the central APA array; and Drift volume D, between the south APA array and the south CPA array

The arrangement of the APAs in the cryostat (and the corresponding arrangement of the spool pieces on top of the cryostat) leads to the following naming convention for the APAs. Each APA is uniquely identified by a ten characters alphanumeric string APA_mxxav, where:

m=1,2 indicates the Single Phase Far Detector module (1 is the first, to be installed in the north cavern, 2 is the second to be installed in the south cavern);

xx=01,….,25 indicates the position of the APA doublet in the north,central, or south array. This number increases monotonically from east to west, with 01 being at the east end of the detector, and 25 being at the west end of the detector, close to the TCO;

a=S,C,N indicates the position of the array (north, central, or south); v=U,L indicates whether the upper (U) or lower (L) APA is being considered.

Figure 3: cross section view of the cryostat for the first Single Phase Far Detector module. The APA and CPA arrays are represented in yellow and red, respectively. Also shown are the east and west field cage endwalls.

Each cryostat penetration for the TPC electronics and the PD is identified by an eight characters alphanumeric string SPA_mxxa, where m, xx, and a have the same meaning as above. The SPA string indicates that this is a spool piece (SP) for the APAs (A). Additional cryostat penetrations and spool pieces are needed for other detector components, as described in Sections XX,YY, and ZZ (need a section with the CPA names with the corresponding cryostat penetrations, a section with the cryostat penetrations for the cryogenic instrumentation and calibration systems, and a section with all remaining cryostat penetrations).

The PD flange corresponding to the cryostat penetration SPA_mxxa will have a name PDF_mxxa, while the two CE flanges will be called CEF_mxxav (in the case of the PD flange there is no need to distinguish between upper and lower APA, as the flange is shared by both). The WIBs in the CE flanges will have a name WIB_mxxavn where the additional index n can assume values between 1 and 5, while the PTC will be called PTC_mxxav. There are then two filter boxes mounted on the CE flange, with a name CEFB_mxxav1 and CEFB_mxxav2, four fans called CEFAN_mxxav1 to CEFN_mxaav4, two RTDs called CERTD_mxxav1 and CERTD_mxaav2, and four heaters called CEHEAT_mxxav1 to CEHEAT_mxxav4.

5

1


3 Cable connections on the CE flangesFigure 4 shows a diagram of the CE flange with the PTC and the five WIBs in the WIEC, plus the two

filter boxes. Four fans provide cooling to the WIEC. Finally, there are two RTDs and four heater on the CE flange. All of these objects have multiple connections that are listed below:

The PTC (called PTC_mxxay) requires four connections:o A 48V power line coming from the WIENER PL506 low voltage power supply on the

detector mezzanine. The 48 V power line contains two AWG10 wires, plus two AWG20 sense wires. The 48V power line has a shield that is connected to the ground (CE flange) both on the PTC side and on the power supply side. The WIENER PL506 low voltage power supplies (one every six APAs, i.e. one per row of APAs) are installed in racks on the detector mezzanine (the exact location has not been specified yet, but it will be in rough correspondence to the APA row).

o An optical fiber connection to the programmable logic controller (PLC) interface of the DUNE detector safety system that is located on the detector mezzanine. This optical fiber connection uses a duplex system of fibers with SC-style connectors and goes directly from the PTC to the PLC interface on the detector mezzanine (one Beckhoff EK1521 is used for each CE flange). There is a total of 30 PLC interface blocks for the TPC electronics in the racks on the detector mezzanine. Out of the 30, 25 are located in racks that are next to the racks containing the WIENER PL506 low voltage power supplies (i.e. one every row of APAs). The optical fibers for the connection to the PLC go from the PTC to the PLC interface block corresponding to the same row of APAs.

Figure 4: schematics of the WIEC, with the five WIBs and the PTC, of the filter boxes, and of the other components installed on the CE flange.

6

1


o An optical fiber connection to the slow control (SC) and the configuration, control, and monitoring (CCM) component of the DAQ. This optical fiber connection uses two fibers with an LC-style connector that are part of a patch cord that goes from the WIEC to an optical patch panel on the PD mini-rack next to the TPC electronics cryostat penetration. The patch cord has 12 individual fibers terminated with an LC-style connector on one side and one single MTP12F-style connector on the other side. The 12 fibers are used to provide SC/CCM connections to the PTC and the five WIBs in the same WIEC.

o An optical fiber connection to the timing system. This fiber goes directly from the PTC to an optical fanout of the timing system that is located on the cryostat mezzanine or in the DAQ room (this is not clear, the DAQ consortium needs to provide details on the location of the optical fanouts of the timing system; the possibility that the optical fanout could be located on the PD mini-rack cannot be excluded).).

Each of the five WIBs (called WIB_mxxav1 to WIB_mxxav5) requires three connections:o Two 10 Gbit/s optical connections that are used to send data from the WIB to the DAQ

backend (the FELIX board). These connections are unidirectional (data flows only from the WIB to FELIX). Each optical connection is realized with a single LC-style connector fiber that is part of a second patch cord that goes from the WIEC to a second optical patch panel on the PD mini-rack next to the TPC electronics cryostat penetration (this patch cord is separate from the patch cord that is used for the SC/CCM connections of the PTC and of the WIBs). The patch cord has 12 individual fibers terminated with an LC-style connector on one side and one single MTP12F-style connector on the other side. Only ten of the 12 available fibers are used, and the last two are not going to be connected and used as spares.

o An optical fiber connection to the slow control (SC) and the configuration, control, and monitoring (CCM) component of the DAQ. This optical fiber connection uses two fibers with an LC-style connector that are part of a patch cord that goes from the WIEC to an optical patch panel on the PD mini-rack next to the TPC electronics cryostat penetration. This is the same patch cord used for the SC/CCM connection on the PTC. It has 12 individual fibers terminated with an LC-style connector on one side and one single MTP12F-style connector on the other side. The 12 fibers are used to provide SC/CCM connections to the PTC and the five WIBs in the same WIEC.

The first of the filter boxes (CEFB_mxxav1) has four connectors, which shall have a name CEFB_mxxav1_1 to CEFB_mxxav1_4. Only the first three connectors are used. They provide the bias voltage to the APA wires. From each connector a RG-59 cable with an SHV connector on both ends goes to a patch panel for the bias voltage distribution located on the detector mezzanine. The shield of the RG-59 cable is connected to the reference voltage (CE flange) both on the PTC side and on the power supply side. The bias voltage supplies and the corresponding bias voltage distribution patch panels are housed in five racks that correspond roughly to rows 03, 08, 13, 18, and 23 of the APAs. Each rack provides the bias voltage to a total of 30 APAs (or five rows of APAs). The bias voltage supplies and the corresponding bias voltage distribution patch panels are not housed in the same racks as the low voltage power supplies and the PLC interface blocks mentioned above for the connection to the PTC.

The second of the filter boxes (CE_mxxav2) has four connectors which shall have a name CEFB_mxxav2_1 to CEFB_mxxav2_4. The second filter box comes in two flavours. For the

7

1


central array of APAs and for the CE flanges corresponding to the lower APAs in the south and north arrays the hardware inside the filter box is identical to that of the first filter box. In this case the filter box is used to provide the bias voltage to the field cage termination electrodes. A variable number of connections is made (between 2 and 4) from the filter box to the same patch panels mentioned in the previous bullet. For CE flanges corresponding to the south and north arrays of APAs the hardware inside the filter box handles channels CEFB_mxxaU_1 and CEFB_mxxaU_2 differently from channels CEFB_mxxaU3 and CEFB_mxxaU4. The first two channels are used like for the first filter box to provide the bias voltage to the field cage termination electrodes. The second two channels are used to monitor the current on the ground planes of the time projection chamber (TPC). All the connections that provide bias voltage to the field cage termination electrodes are realized using the same RG-59 cable with an SHV connector on both ends that goes to a patch panel for the bias voltage distribution located on the detector mezzanine. The connections for the monitoring of the ground plane currents are realized with ??? (the HV consortium should specify the type of cable and where the cable is going to).

The four fans (CEFAN_mxxav1 to CEFAN_mxxav4) are connected to two elements of the PLC system in the racks on the detector mezzanine (these PLC elements are located in the same racks that contain the Beckhoff EK1521 used in the interface to the PTC, i.e. one rack every six APAs) via a pair of cables with eight AWG24 wires. One cable serves the first two fans and the second cable serves the second two fans. Four of the wires in each cable are used to provide power to the fans. These eight wires used to provide power to the four fans are connected to a Beckhoff EL2034 power fanout module on the PLC. The remaining wires are used to monitor the status of the fans and are connected to a Beckhoff EL1004 digital input module on the PLC. On the fans side two of the wires (those connected to the +24 V terminal on the fan) are shorted: one of the wires receives the +24 V from the EL2034, and the other line sends the +24 V back to the EL1004 (need to check with Trevor Nichols and Linda Bagby that this is how we are going to do the connections).

The two RTDs (CERTD_mxxav1 and CERTD_mxxav2) are connected to one element of the PLC system in the racks on the detector mezzanine (a Beckhoff EL3202-0010) each through one AlphaWire 1214C SL002 cable (each of these cables contains four AWG24 wires). (Need to specify where the shield of this cable is connected).

The four heaters (CEHEAT_mxxav1 to CEHEAT_mxxav4) are connected to one element of the PLC system in the racks on the detector mezzanine (a Beckhoff EL2024) via two AlphaWire 1896/4L SL002 cables. The first cable serves the heaters CEHEAT_mxxav1 and CEHEAT_mxxav2, while the second cable serves the heaters CEHEAT_mxxav3 and CEHEAT_mxxav4. Each of these cables contains four AWG20 wires). (Need to find a shielded version of this cable, specify where the shield is connected).

The PD flange corresponding to the cryostat penetration SPA_mxxa will have a name PDF_mxxa, while the two CE flanges will be called CEF_mxxav (in the case of the PD flange there is no need to distinguish between upper and lower APA, as the flange is shared by both). The WIBs in the CE flanges will have a name WIB_mxxavn where the additional index n can assume values between 1 and 5, while the PTC will be called PTC_mxxav. Table 1 gives an example of the decoding of the names for the APAs, spool pieces, PD and CE flanges, WIBs, and PTC.

8

1


[4] Fiber connections on the optical patch panel on the PD minirackThe TPC electronics consortium needs a 1U patch panel in the photon detector mini-rack close to one

cryostat penetration where to make the connections between the patch cords coming from the WIBs and the PTCs for the two CE flanges associated to that cryostat penetration. As discussed in the previous section there are two patch cords coming from each of the two CE flanges: one patch cord carries the data from five WIBs that should be sent to the FELIX card associated to that flange, while the other patch cord is used for the communication between the five WIBs and the PTC in that WIEC and the SC/CCM computer(s) on the other side. Both patch cord are terminated in a MTP12-F connector. The simplest way to realize a patch panel for the fibers is to have a 1U rack mount FHD modular fiber enclosure panel (see for example https://www.fs.com/products/70419.html) on which one FHD adapter panel is installed (see for example https://www.fs.com/products/35510.html). The TPC electronics consortium would use only 4 of the 12 possible connection in the FHD adapter panel (in principle there could be a single patch panel of this kind for one row of APAs, but this would require long patch cords going from one cryostat penetration to another; given the relatively small cost of the enclosure panel and of the FHD adapter panel it is very likely that the cheapest solution is to have this patch panel in each PD mini-rack). The fiber enclosure panel allows for additional fiber connections, that could be used by the PD consortium. In the patch panel the patch cords coming from the two CE flanges would arrive from the back and the MTP12-M terminated ribbons going to the DAQ room would be plugged in the front. Two of the ribbons would go to patch panels in the DAQ room located near the network switches, while the two others would go to the racks housing the FELIX cards. Figure 5 shows the schematics of the connections on the optical patch panel on the PD mini-rack. The patch cords coming from the WIBs/PTCs are terminated in a MPT12-F connector. The ribbons that plug into the patch panel and go to the DAQ room are terminated in a MTP12-M connector.

9

https://www.fs.com/products/35510.html

https://www.fs.com/products/70419.html

1


Figure 5: schematics of the optical patch panel close to the PD mini-rack. The TPC electronics consortium uses 4 ports on the FHD adapter panel to mach the patch cords coming from the CE flanges to the ribbons going to the DAQ room.

4[5] Racks on the detector mezzanine used by the TPC electronics consortium

5[6] Cable connections on the detector mezzanine

6[7] Fiber connections on the cryogenic mezzanine and the DAQ room

10

Documents

Introduction · Web viewIn addition, there are two filter boxes mounted on each CE flange, plus a system of heaters to prevent condensation on the flanges, and a system of fans to