> **NuMI-L-634**

**May 9, 2000**

**Far Detector Checkout and Commissioning:**

**Facilities and Procedures (WBS 2.4)**

**D. Ayres, W. Miller**

Version 1.3

**OUTLINE**

1.  **Electronics systems**

    -   Relay racks, electronics crates and components

    -   MUX boxes

    -   Light flasher boxes

    -   Detector control system

    -   Storage at Soudan

2.  **Cabling and cable trays**

    -   Fiber optics on detector

    -   Networking, low and high voltage, signal lines,

    -   Location of cable trays

3.  **Plane checkout and commissioning procedures**

    -   If final electronics is operational

    -   Wire source scan with stand-alone electronics

4.  **Magnet Coils**

    -   Coil components

    -   Installation

    -   Commissioning

> **5. Magnetic monitoring equipment**

-   Installation

-   Commissioning

6.  **Work areas for detector control and computing**

    -   Counting house

    -   Control room

    -   Surface

**1. Electronics systems (WBS 2.2 and 2.3)**

*The material in this section will eventually be combined with the
material in NuMI-L-591, "Crate and Cable Layout for the MINOS Far
Detector," by Rob Plunkett. Much of the material in that note is
summarized here.*

> **1.1 Relay racks, electronics crates and components**
>
> Approximately one hundred electronics racks must be assembled, with
> components installed and tested, to control, monitor and read out both
> supermodules. As soon as we have beneficial occupancy of the MINOS
> Hall we need to begin rack installation. After the first front-end
> racks are installed, additional ones can be added as installation
> proceeds, but most of the mid-level racks for the first supermodule
> will need to be installed at the start of the installation period.

-   **Front-end racks**

> Each front-end rack contains 8 MUX boxes with front-end electronics
> boards (VFBs). Low and high voltage power cables for these racks are
> run in horizontal and vertical cable trays from the mid-level racks.
> The only AC power needed in the front-end racks is 120 V for smoke
> detectors. The components in each rack use up about 47" of the 70"
> available vertical space. The MUX boxes will have been bench tested
> after delivery to Soudan and are ready to be mounted in the racks. The
> front-end VFBs are pre-tested before shipment. They are mounted on
> standoffs on the sides of the MUX boxes, after they are installed in
> the racks. Once the electronics is in place, signal and low voltage
> cables are connected. A small metal Faraday cage is installed over
> each VFB to eliminate potential rf noise pick-up. Each Faraday cage is
> grounded only through its low and high voltage cables. Each MUX box
> chassis is isolated from all other grounds.

-   **Front-end electronics**

> Once a new VFB is connected, the electronics chain is tested with
> charge-injection events. Then tests are run using signals from the
> MUX-box PMTs, to make sure the dynode signals are getting through,
> that the thresholds are reasonable, that the tubes aren't too noisy.
> The electronics-only portion would use a special operating mode of the
> DAQ system and would take about 1-2 hour. A minecrew electronics
> technician could eventually do the tests, but initially they will be
> done by physicists/students assisted by a technician.
>
> *Additional information to be supplied by electronics task*

-   **High Voltage racks**

> Each mid-level High Voltage rack holds a LeCroy 1440 mainframe and
> associated equipment, and there are 4 HV racks per supermodule. Each
> mainframe can hold up to 16 cards, each with 16 separate computer
> controllable channels. Each mainframe will have up to 256 HV cables
> coming out the back and running to the MUX Boxes on the top and bottom
> levels. They will run down the cable tray in the middle level in Z and
> the run up/down to the appropriate front-end rack. HV cables will not
> run in the same tray as fiber optics. All LeCroy 1440 mainframes and
> HV boards will be tested and certified by Fermilab. It will take about
> 12 man-hours to check out one supermodule's worth of HV racks. It will
> take about 1 man-hour/plane to cable and test each MUX box. A
> freestanding Sola power-conditioning transformer, with 208 V input,
> provides the AC power for each HV rack.

-   **VME racks**

> Each VME-crate rack contains a VME readout crate, magnet monitor PCs,
> a light flasher unit and rack protection chassis. The low-voltage
> power supplies for each pair of VME racks are contained in a separate
> rack, each requiring about 3000 W of input power. There are four
> VME-crate racks and two power supply racks on each side of each
> supermodule. All VME racks for a supermodule must be installed before
> its detector planes can be read out. Special analog signal cables
> between the VME crates and the front-end electronics must be as short
> as possible. The VME power supply racks also provide low voltage power
> cables for the front-end racks. To minimize the distance between the
> VME and front-end racks, there will be a hole cut in the floor next to
> each front-end rack and a vertical cable tray will be provided.

-   **Auxiliary racks**

> Trigger crates, DAQ computer, GPS and clock systems will be located in
> racks on the mid-level walkways or the control room. The location and
> specifications of the control room have not yet been finalized (see
> Section 6 below).

![](media/image1.jpeg){width="6.997916666666667in"
height="5.836805555555555in"}

> *[Insert here additional rack drawings, including population of each
> rack]{.underline}*
>
> **1.2 MUX boxes**
>
> MUX boxes arrive at Soudan at the rate of about 25 boxes/month. Each
> box is opened up for a visual inspection, and then tested for light
> leaks and the presence of a dynode-out signal. This will take about
> 1.5 man-hours per box. Once a box has been tested it is placed into a
> front-end rack and is then ready to be cabled up.
>
> **1.3 Light flasher boxes**
>
> There are 16 rack-mounted boxes, 4 on each side of each supermodule
> (in the VME-crate racks). Flasher boxes are delivered to Soudan at a
> rate of one/month and are installed on arrival. A bundle of twenty
> optical fibers runs from each side of each plane to the associated
> flasher box. A total of 1200 optical fibers runs from each flasher box
> to detector modules. The checkout procedure for the light flasher
> boxes at Soudan has not yet been specified.
>
> **1.4 Detector Control System (DCS)**
>
> *This section will list components and delivery schedules, summarize
> checkout procedures and installation-time estimates, and describe what
> is in each relay rack.*
>
> **1.5 Storage**
>
> Our original plan was to store all electronics, cables, MUX boxes,
> racks etc. in the northeast bay of the mezzanine in the Soudan 2 Hall.
> It is now likely that the entire mezzanine will be needed for
> scintillator module storage. We now plan to store electronics
> components in the electronics work area (old Soudan 2 cleanroom) and
> to store other components on the large steel storage rack, which will
> be moved from the Soudan 2 Hall into the south end of the MINOS Hall.
> This seems like a better location anyway, as it is closer to the
> detector where the installation will take place.

**2. Cabling and cable trays**

**2.1 Fiber optics cabling**

-   **Scintillator modules to MUX boxes**

> The clear fibers running from the scintillator modules to the MUX have
> their own special cable trays that support the fibers in Z. Additional
> strain relief for the cables is provided at the MUX boxes. The
> upper-level trays are mounted to angle brackets that also hold the
> safety guard rails. The exact width of this cable tray will be
> determined after completion of prototype work at Fermilab in May 2000.
> The bottom-level clear-fiber cable trays have not yet been designed
> but will be similar to the top ones, supported by brackets coming off
> the detector support structure. The Z-distance between front-end racks
> is 6 ft. The clear fibers are contained in fire-resistant and
> light-tight plastic tubes ("conduits"). These tubes are installed on
> the outer periphery of each plane while it is on the strongback,
> before it is mounted on the detector. It is critical that the fibers
> are not bent past the minimum bend radius of 12 cm during
> installation. The cables must be carefully uncoiled and restrained as
> they are fed through the cable tray to the MUX boxes.

-   **Light flasher**

> The flasher system has two sets of 20 fibers coming from each side of
> each detector plane. These fibers enter the mid-level cable tray on
> the side closest to the detector (also used for scintillator-to-MUX
> cables) and run in Z to the mid-level flasher boxes. These cables must
> also be handled carefully to maintain the minimum bend radii. Each
> flasher box also provides LED signals to PIN diodes via two fiber
> optics cables to each MUX-box VFB board. Flasher system communication
> uses RS485 daisy-chained serial lines connecting all boxes, or
> alternatively, they may use the DCS LAN and an Ethernet-to-RS485
> adapter for each flasher box.

-   **Fiber optics cable trays**

> The fiber optics cable tray, used for supporting the Z runs of
> scintillator-module to MUX-box cables, is shown in the following
> figure.
>
> ![](media/image2.jpeg){width="3.9881944444444444in"
> height="2.5034722222222223in"}

**2.2 Networking, low and high voltage, signal lines**

-   **Local Area Networks**

There are three separate LANs and a PVIC network running around the
detector, for DAQ, DCS and Internet access. All cable trays will be of a
hanging "T" style in the middle and lower levels. All non-fiber cables
are run on one side of these trays and the fiber optics cables on the
other side.

-   **DAQ**

Data from the VME crates are transferred to the Readout Coordinator PC
in the control room on a PVIC network and from there to the trigger
processors (also via PVIC). The PVIC network cabling runs in a loop in
the mid-level cable tray all the way around the detector and back to the
control room. The data are transferred through a (short) Ethernet LAN
connection from the trigger processors to the nearby DAQ computer.
During the first three months after beneficial occupancy the PVIC
network and DAQ LAN cabling, along with most other infrastructure, will
be installed, tested and debugged. The engineers and physicists who
designed it will be responsible for installing and commissioning this
system.

All front-end processors (ROPs) use the DCS LAN for diagnostic and
network-time communications, but not for data transfer or control
functions.

-   **Detector Control System**

This is a separate LAN just for the DCS. It will run in both the lower
and middle level cable trays, with spurs up to the top level where
needed.

-   **Internet**

This LAN is used for outside access to the Internet. We also use it for
sending data from the control room for storage at Fermilab. The Internet
LAN is located in the lower and middle level cable trays, with spurs up
to the upper level. There will be numerous plug-ins located throughout
both the Soudan 2 Hall and the MINOS Hall for laptops and other
equipment.

-   **Telephones**

We are currently installing a new telephone system at Soudan. The main
hub will be in the Soudan 2 Counting House. The system can accommodate
36 phones and a paging system, for both the Soudan 2 and MINOS Halls. A
conference call and video room will be located on the first floor of the
Counting House. Video-conference facilities will be provided as soon as
adequate bandwidth is available. These cables will run in all lower and
middle cables as needed.

-   **High Voltage**

The HV cables run from the HV racks located in the middle level to the
MUX boxes located in the front-end racks on the upper and lower levels.
The upper-level cables run in Z on the cavern-wall side of the
middle-level cable tray to the appropriate MUX boxes above. They then
run in small vertical cable trays running though holes cut in the upper
deck. The HV cables for the lower level MUX boxes drop through the floor
in vertical cable trays located next to the HV racks. From there, they
run in Z on the cavern side of the cable tray until they get to the
appropriate front-end racks. Each MUX box holds three PMTs, each with
its own cable. There are 24 HV cables running to each front-end rack.

-   **Low Voltage**

The LV cables run from the power supplies located in the VME racks on
the middle level to the front-end racks above and below them. They use
the same routing and vertical cable trays as the HV cables. Each
front-end rack as its own vertical cables tray. While the cable trays on
the top layer have been planed out the path to the lower level racks has
not been located yet. There is a 0.25" diameter, shielded, 2-
twisted-pair cable for each MUX box. Since each VME rack feeds 4
front-end racks (two upper and two lower), each containing 8 MUX boxes,
there are 32 LV cables coming out of each VME rack.

-   **VME-crate to MUX-box data cables**

A 1.25-inch wide digital-control ribbon cable transmits digital
information from the front-end electronics, located on the side of each
MUX box, to the appropriate VME rack on the middle level. In addition,
the VA-to-ADC analog cable (similar in size to RG-174) carries VA-chip
data from the MUX box to the VME rack. Rack locations and cable-tray
routes are carefully planned to minimize the lengths of these cables.
There is only one analog cable per MUX box, so 8 cables from each of the
4 front-end racks will feed into a single VME rack. All low-voltage,
digital-control and analog cables from a MUX box are installed in a
single bundle to avoid ground loops.

-   Location of cable trays

> Cable-ray locations are shown in the following figure:

![](media/image3.jpeg){width="6.991666666666666in" height="7.1125in"}

**3. Plane checkout and commissioning procedures**

As soon as a plane has been mounted to the detector it undergoes a
series of short checks to ensure there is no major problem. It can still
be removed for repair until the next plane assembly begins on its
strongback. The first planes installed will have several hours (or more)
of test time before they are closed up forever. After the half-rate
installation period has started, the time window available to remove a
plane for repair is expected to be about an hour.

Front-end, VME and DAQ racks will be installed before the first planes
are mounted. As soon as a plane is mounted, its axial-rod bolts
installed and its strongback removed, all the flasher and clear fiber
cables are uncoiled and plugged into the appropriate racks. A first
system test (for light leaks) is run at this point and the flasher
system is used to check for broken fibers or other problems. These
checks require the final electronics system to be operational.

*The scintillator and electronics groups will add details to this
section.*

**4. Magnet Coils**

*Details of coil construction, installation and checkout will be
provided by the steel and coils group.*

-   Coil components

-   Installation

-   Commissioning

**5. Magnetic monitoring equipment**

*The steel and coils group will provide details of magnetic monitoring
system assembly, installation and checkout.*

-   Installation

-   Commissioning

**6. Work areas for detector control and computing**

-   Counting house

> The existing counting house in the Soudan 2 Hall consists of two
> floors. The top floor houses the lunchroom facilities and has been
> remodeled to comfortably serve about 24 people per shift. It has
> microwaves, toaster and pizza ovens and refrigerators. Individual
> workers bring their own food. The first floor of the counting house
> has two rooms, the largest of which holds the computers currently used
> for processing Soudan 2 data. These computers, currently two PCs and
> four VAX workstations, can also be used to connect to the Internet and
> work on MINOS. This room is also used for teleconferences and has a
> small conference table for 6-8 people. Videoconferences will be held
> here when the facilities are available. The smaller room on this level
> is currently used for tape copying and archiving of Soudan 2 data. It
> also houses all of the telephone and LAN equipment needed to
> communicate between the underground labs and the surface. The
> communication uses the12-fiber optical data cable that is being
> installed in the shaft as part of the installation task.

-   Control room

> We currently plan to locate the control room on the observation
> platform above the assembly workstations, although other locations,
> such as the south-end storage area, are also under consideration. The
> observation platform has approximately 10\' x 60\' available for this
> purpose. The size and area of the control room have not yet been
> determined. This area on the observation platform can accommodate two
> or three small rooms, one for the control room and the rest for office
> space for the supervisors, coordinators and shift leaders. These rooms
> will be insulated from the noise below. The control room will house
> the computers for the DAQ, trigger farm and the detector control
> system. It will also have three or four desks with PCs for shift
> physicists. The installation crew will install these rooms after
> beneficial occupancy.

-   Surface Building

> The surface building will serve as both the steel-bundling facility
> and the receiving and shipping facility. All UPS, FedEx and other
> freight will arrive at the surface building, which is located next to
> the Breitung Township Hall. The building is owned by the township and
> rented to us under a 7-year lease. The surface building office has a
> direct computer link to underground lab and to the database for
> tracking shipments and inventories. The crew boss assigned to the day
> shift will also be responsible for maintaining office, kitchen,
> laboratory and sanitation supplies. He is in direct contact with the
> University of Minnesota billing department that issues our POs and
> pays the bills. This crew boss is also responsible for coordinating
> and scheduling the preparation of large detector parts (steel bundles,
> scintillator crates, electronics cables, etc.) that are to be moved
> underground.
>
> The surface building contains a lunchroom for people working on the
> surface. These crews will also have a pickup truck or other vehicle
> for running between the headframe and the surface building and hauling
> small loads. The large hauling truck will handle the steel bundles,
> scintillator boxes and pallets. There is also a small shop for minor
> repairs to surface equipment as well as all tools, slings, etc. needed
> for moving material and equipment underground.
>
> If it is needed, additional office space may be added on the mezzanine
> above the lunchroom and office area. This area is currently designated
> for light storage.