Safety Review Document for the Preamplifier System for the Cold Bo DAQ System -------------------------------------------------- Initial Rev. 25-May-2011 Current Rev. 15-June-2011 This document covers the power supplies and the associated components for the front-end of the Bo Cold DAQ system. The contact person for this equipment is: Dan Edmunds Fermi Phone: x2832 MSU Phone: 517-884-5521 Email: edmunds@pa.msu.edu The parts of the Bo Cold DAQ system that are covered by this review are: the Preamp and Driver Power Supply, the Fuse and Power Distribution Panel, the Warm Receiver and Power Cards 16 channel (WRP-16), and all the associated cables that carry power. The parts of this DAQ system that are not covered in this review are: the preamplifiers that are sealed inside the Bo cryostat, and the Wiener VME crate with its Bit-3 and ADF-2 cards (this was previously reviewed in July 2008 and there have been no changes to this equipment). The Cold Bo DAQ system components under review are located in the DAQ rack next to the Bo cryostat and in a small card file on the readout port of the Bo cryostat. The Bo cryostat is located in the main shop area of the Proton Assembly Building (PAB). The components of this system (given in the order that power flows through them) are: Preamp and Driver Power Supply, Preamp and Driver DC Power Cable, Fuse and Power Distribution Panel, WRP-16 cards, and Cables to the Readout Port Signal Feedthrough on the Bo cryostat. Each of these components is described in a separate section of this note. A general block diagram showing the overall layout of the power supply equipment for the Bo Cold DAQ System is available on the web at: http://www.pa.msu.edu/~edmunds/LArTPC/Bo_Cold_DAQ/Safety_Review/ bo_cold_daq_block_diagram_power_system.pdf This document itself is also available in this same directory on the web. Preamp and Driver Power Supplies -------------------------------- The Preamp and Driver Power Supply chassis contains 4 separate commercial linear open frame power supplies. A schematic drawing of the Preamp and Driver Power Supply is available at: http://www.pa.msu.edu/~edmunds/LArTPC/Bo_Cold_DAQ/Safety_Review/ bo_cold_daq_power_supply_chassis.pdf The 4 supplies in the Preamp and Driver Power Supply chassis provide power to 4 loads in the Cold Bo DAQ system. The supply voltages and loads are: The +9 Volts supply provides a total of about 1.6 Amps to the Preamp Vcc regulators on the WRP-16 cards The -9 Volts supply provides a total of about 1.4 Amps to the Preamp Vee regulators on the WRP-16 cards The +5 Volts supply provides a total of about 1.9 Amps to the Driver Vcc load The -5 Volts supply provides a total of about 1.9 Amps to the Driver Vee load The +9 and -9 Volt power supplies are Condor Model MC12-3.4A that are rated for 12 Volts output at 3.4 Amps. These supplies have been set for a 9.10 Volt output. The +5 Volt and -5 Volt supplies are Elpac model SOLV30-5. This model supply is rated for 5 Volts at 6 Amps. These supplies have been set for a 5.11 Volt output. All 4 supplies are protected by 2 Amp fuses at their input and by 5 Amp fuses at their output. These fuses are located immediately adjacent to each supply. In addition the AC power coming into the Preamp and Driver Power Supply chassis has a 5 Amp fuse in each side of the line before it goes to any loads. There are separate front panel indicator LEDs and tip jack test points for each of the 4 supplies. These components and wiring are protected by separate 3 Amp pico fuses located immediately adjacent to the supply's output terminals. The DC output from the Preamp and Driver Power Supply chassis is provided on two Wieland terminal strips. The contacts in these terminal strips are rated for 30 Amps each and are used to connect the power supply outputs to the Preamp and Driver DC Power Cable. Preamp and Driver DC Power Cable -------------------------------- The Preamp and Driver DC Power Cable is about 15 ft long and carries power from the power supply chassis over to the Fuse and Distribution Panel above the WRP-16 card file. This power cable is shown in the following schematic drawing on the web at: http://www.pa.msu.edu/~edmunds/LArTPC/Bo_Cold_DAQ/Safety_Review/ bo_cold_daq_dc_power_cable.pdf This cable carries power for both the Preamp Regulators and the Driver circuits on the WRP-16 cards. There are 4 wires in this power cable for each circuit: a Vcc wire, a Vee wire, and two return wires. All of these wires are 14 AWG with 105 deg C insulation. Each set of 4 wires is twisted together. There is a woven plastic sleeving around the overall cable. At the Fuse and Power Distribution Panel end of the cable there are 2 Cinch-Jones connectors, one for each circuit. The Vcc and Vee supply are each carried on one contact of the Cinch-Jones connector for that circuit. The return lines for that circuit are carried on two contacts and the alignment pin of the connector. Each contact of the connector is rated for 15 Amps. Fuse and Power Distribution Panel --------------------------------- Power from the cable described above enters the Fuse and Power Distribution Panel on 2 Cinch-Jones connectors. From these connectors #14 wire is used to distribute the power to the fuses that feed each of the panel's output "drop cables". The Fuse and Power Distribution Panel is mounted above the card file that holds the 9 WRP-16 cards. Drop cables reach down from the Fuse and Power Distribution Panel to the WRP-16 cards. For each WRP-16 card that are separate "Preamp" and "Driver" drop cables feeding power to it. The Fuse and Power Distribution Panel is shown in the following 2 drawings. All of the parts are mounted on one panel but 2 drawings were used for clarity. http://www.pa.msu.edu/~edmunds/LArTPC/Bo_Cold_DAQ/Safety_Review/ bo_cold_daq_fuse_panel_preamp.pdf bo_cold_daq_fuse_panel_driver.pdf The Fuse and Power Distribution Panel has separate fuses for each output drop cable. There is a 2 1/4 Amp fuse in each of the 4 supply voltages that go to each of the 9 WRP-16 cards. The drop cables that carry the power from the fuse panel to each WRP-16 card are made with 22 AWG wire. Each WRP-16 card has one cable for its "Preamp" power and another cable for its "Driver" power. The connectors that plug these cables into the WRP-16 cards are made with 6 position AMP MOD IV housings and AMP high pressure contacts. The contacts are AMP/Tyco part number 1-87309-4 Newark stock number 90F3791. These contacts are rated for 3 Amps each. The current rating specification for these contacts is available from AMP/Tyco web site at: http://catalog.tycoelectronics.com/TE/bin/ TE.Connect?C=1&PN=1-87309-4&M=BYPN&LG=1&I=13 WRP-16 Cards ------------ The WRP-16 cards receive "already fused power" on 2 connectors. Each connector is a 6 pin header of 25 mil square pins. One connector is for the "Preamp" power and the other connector is for the "Driver" power. The WRP-16 card is protected from spikes and reverse polarity by a Transient Voltage Suppressor in each of its power entry filters. Input power is also cleaned up by bulk Aluminum electrolytic and Tantalum capacitors before it reaches the actual electronics on the card. Both the "Preamp" and the "Driver" power circuits have a common mode choke at their input to WRP-16 card to filter noise and to help break the ground loops. The WRP-16 card can been seen in the following 2 pictures on the web. You can see where power is received by the 2 six pin headers on the right edge of the top picture of the WRP-16 card. http://www.pa.msu.edu/~edmunds/LArTPC/Bo_Cold_DAQ/Camera_Pictures/ warm_receiver_power_wrp_16_top.jpg warm_receiver_power_wrp_16_bot.jpg The power connectors on the WRP-16 card are rotationally symmetric, i.e. if one is plugged in rotated by 180 deg it makes no difference. If a connector is plugged in offset by one pin then it will directly short circuit the supply and blow the 2 1/4 Amp fuse on the fuse panel (the card itself will not see any significant supply voltage). If the connector for the "Preamp" supplies is exchanged with the connector for the "Driver" supply nothing is damaged. The WRP-16 card will not work well with these connectors interchanged but nothing is damaged. On the WRP-16 card power is carried on power planes of 1 ounce Copper so there is not really an issue about sufficient trace width to match the 2 1/4 Amp fuses that protects the card. Gerber files of the WRP-16 card are available on the web at: http://www.pa.msu.edu/~edmunds/LArTPC/Bo_Cold_DAQ/WRP_16_Release_1/ A drawing of the circuits on the WRP-16 card is available on the web at: http://www.pa.msu.edu/~edmunds/LArTPC/Bo_Cold_DAQ/Bo_Cold_DAQ_Drawings/ warm_receiver_power_16_ch.pdf The lower left-hand side of this drawing shows the power entry filter design. There are separate power entry filters for the "Preamp" power and for the "Driver" power. The "Driver" power just supplies the 16 Line Drivers on the WRP-16 card. The circuit design of the Line Driver is shown in the upper right-hand corner of this drawing. The "Preamp" power is the input supply to 4 regulator circuits on the WRP-16 card. These 4 regulators supply power to the cold electronics that is inside the Bo Cryostat. One of these regulators is shown in the lower right-hand corner of the WRP-16 card's circuit drawing. Each of these 4 regulator circuits includes a 500 mA fuse in its output. The output from these regulators is carried into the Bo Cryostat by the Signal Feedthrough card that is mounted in the readout port of the Bo Cryostat. The outputs from the regulators on the WRP-16 card are connected to the Signal Feedthrough card by a 50 conductor flat cable. WRP-16 Card Regulator Outputs into the Bo Cryostat -------------------------------------------------- The 500 mA fused output from each regulator on the WRP-16 card is carried by 2 parallel wires in the 50 conductor flat that connects the WRP-16 card to the Signal Feedthrough card. The parts used in this cable connection are the following: WRP-16 card board mount connector: 3M Part 81050-660203-RB Cable mount connector at the WRP-16 end of the cable: 3M Part 82050-6006-RB 50 conductor polyolefin flat cable: 3M Part 2049/50 Cable mount connector at the Signal Feedthrough end of the cable: 3M Part P50-100P-S1-EA Signal Feedthrough card board mount connector: 3M Part P25E-100-S-EA All of these connectors are rated at 0.5 Amp per pin. The 50 conductor flat cable uses a #30 solid wire for each conductor. #30 wire in large bundles is rated for 1.1 Amps. The diagram that shows this cable connection best is the bottom half of the drawing: http://www.pa.msu.edu/~edmunds/LArTPC/Bo_Cold_DAQ/Safety_Review/ bo_cold_daq_block_diagram_power_system.pdf This cable connection can be seen in the following picture just to the right of the vertical pipe that has the label "High Voltage" on it: http://www.pa.msu.edu/~edmunds/LArTPC/Bo_Cold_DAQ/Camera_Pictures/ bo_tpc_and_cold_electronics_insertion.jpg From the Signal Feedthrough card on all of the rest of the power distribution components for the Bo Cold DAQ System are sealed inside the Bo Cryostat.