Solenoid expert pxi

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Revision as of 10:27, 24 March 2022 by Zihlmann (Talk | contribs) (Reboot PXI Chassis)

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Basic Information

A PXI system is built and configured to monitor the vital signals of the Hall-D super-conducting magnet to ensure its safe operation, particularly to detector the turn-to-turn short faults. Currently, the system contains 4 ADC modules which can sample up to 32 channels simultaneously at a maximum rate of 250 kHz. A LabVIEW RT program is automatically loaded and executed when the system is booted as a stand alone turn-key system. Through its Ethernet connection, the system hosts an EPICS server so that the measurements can be easily accessed and archived remotely. It also serves as an Ethernet device to the magnet control system based on PLC to provides various readings including current, field and voltages.

A technical note is available on GlueX DocDB - doc-2016

Information for the period of solenoid commissioning can be found here


  • hostname:
  • ip address:

List of EPICS PVs

Control PVs
  • HallD-PXI:Control:Start: start DAQ
  • HallD-PXI:Control:Stop: stop DAQ
  • HallD-PXI:Control:Quit: quit the LabVIEW-RT program
  • HallD-PXI:Control:Zero: take 1-minuite data to calculate offsets of all channels
  • HallD-PXI:Control:Reset: reset offsets of all channels
  • HallD-PXI:Control:ForceAlarm: force the turn-to-turn alarm to be true
Status PVs
  • HallD-PXI:Status:Beat: heart beat, updating at 1Hz
  • HallD-PXI:Status:Status: indicator of current machine status
  • HallD-PXI:Status:State: state bit: 0 not running, 1 initialization, 2 running, 3-7 other running
  • HallD-PXI:Status:Error: error bit of the LabVIEW-RT program
  • HallD-PXI:Status:Message: error message of the LabVIEW-RT program
  • HallD-PXI:Status:CPU: CPU usage of the PXI system
  • HallD-PXI:Status:Interval: Time interval between two EPICS updates
  • HallD-PXI:Status:Jitter: Jitter of time intervals
  • HallD-PXI:Status:FIFO: Buffer depth for local data writing, depleted when reaches 1
  • HallD-PXI:Status:Alarm: turn-to-turn short alarm bit
Data PVs
  • HallD-PXI:Data:I_Shunt: current measured by a shunt resistor (reliable)
  • HallD-PXI:Data:I_Sol: current reading by the magnet power supply (MPS), not very reliable
  • HallD-PXI:Data:B_Field: magnetic field measured by a Hall probe
  • HallD-PXI:Data:V_MPS: voltage output of the MPS
  • HallD-PXI:Data:VTTn: voltage across subcoils and leads, n = 3 - 21
  • HallD-PXI:Data:V_PCnX: voltage induced in pickup coils, n = 1 - 4, X = U or D for upstream or downstream coils
  • HallD-PXI:Data:Det_QD: quench detector error signal
  • HallD-PXI:Data:Det_GFD: ground fault detector error signal


Check PXI Status

From the EPICS Main GUI, open the Voltage Taps/PXI screen. The PXI status and control can be found at the bottom left of the screen. Make sure the PXI is in DAQ Running state and the Heart Beat LED is blinking.

Reboot PXI Chassis

Option I - local power cycling
  1. Climb the ladder and reach the top of the magnet where the PXI system is located.
  2. Reboot the PXI by pushing the power button in the front panel.
Option II - using remote PDU
  1. The power to the PXI system is distributed by a CyberPower PDU unit, the PXI can be rebooted using the PDU's web interface.
  2. Go to (IP:
  3. log in using user name localadmin and corresponding password (ask Beni[1] for password).
  4. In the left panel, click Control
  5. Check the Loads box to see a list of all connected devices.
  6. Use Shed Action button to reboot the PXI

High Speed DAQ

While high speed data are always served by the PXI EPICS IOC, another EPICS IOC server is set up on to write the data to /gluonraid1/Users/PXI directory on demand.

The control of High Speed DAQ is in the Voltage Taps/PXI GUI. Start or Stop the High Speed ROOT File by clicking the button underneath the title. Once started, make sure the a new ROOT file is created and the File Size is increasing. If not, one need to restart the pxiroot EPICS IOC:

Reboot through CSS GUI
  1. In the Main Action Bar, click Status of IOCs
  2. In the IOC Status screen, click the Solenoid PXI Interface and choose View Status of IOC for Solenoid PXI Interface
  3. In the IOC Diagnostics for Solenoid PXI screen, click Hard Reboot to restart the IOC.
  4. Verify that the all the connections to the IOC are reestablished after the reboot: no pink boxes in the PXI screen.
Reboot using command lines;
  1. Log onto gluon29 using hdsys account
  2. telnet localhost 26060
  3. Restart the IOC by keyboard combination Ctrl+X
  4. Exit the IOC proServer by keyboard combination Ctrl+]
  5. Exit the telnet by typing quit

Analyze High Speed Data

From Voltage Taps/PXI GUI
  1. Click the Analyzer button in the PXI Fast DAQ section.
From a Linux terminal
  1. log onto a gluon machine, e.g., using account hdops: ssh -X hdops@gluon30
  2. enter the solenoid directory: cd ~\solenoid
  3. start the analyzer script: ./run
  4. in the analyzer, open a collection of raw data files or a processed ROOT file and start the analysis.