Previous Page Main Page What to do while on shift DAQ Trouble Shooting Guide

How to take a special run with different APD voltage settings

In this "special run", we will operate the detector with non-default APD voltage settings. This requires, in order:

  1. stopping the DAQ system
  2. setting the APD voltages in the configuration database and generating new scripts to set the APD voltages
  3. performing a DSO scan at that voltage to determine new thresholds and uploading new channel thresholds and masks into the database
  4. starting a new data taking run

How to stop the DAQ system

If a terminal is not already open on nova-daq-01 with user "novadaq" connected to "", then type the following commands in a terminal:

  1. ssh
  2. setup_online


  1. End the current run
    • Click "End Run" in the RCMainWindow
  2. > (closing all Run Control GUI applications)
  3. > stopSystem (stopping all DAQ applications)
    • WAIT until the System is stopped!

How to set the APD voltage in the configuration database

The next step is to change the voltage settings in the appropriate DAQ hardware configuration database table. The easiest way to do this is to use the DCS Configuration Editor :

  1. Double-click on the "DCS Config Editor" icon on the nova-daq-01 desktop to open the DCSConfigEditor GUI.
  2. Click on the APD High Voltages tab
  3. Change the cold and warm voltage settings (currently there are only two for the "Full System") to the desired value. (To change a value in the GUI, double-click on the value. A single mouse click simply selects the value, whereas a double-click enables editing of the value.) The units here are not in Volts; the table should be used to do the conversion:
V Warn ADC Setting Cold ADC Setting
300 0 0
310 410 0
320 819 0
330 1228 0
340 1638 214
350 2048 624
360 2457 1033
370 2866 1442
380 3276 1852
385 3481 2057
390 3686 2057
400 4095 2057

Note that the default "warm" setting at NDOS is 375V, with a warm ADC setting of 2957 and a cold ADC setting of 1533.

  1. After changing the voltages, save the changes to the database via the menu: File -> Save
    • (Please note that you may need to move the focus away from the value that you just edited in order to get the Save option to be enabled. To do this, simply single-click on a cell in the table that is different from the one that you just edited.)
  2. After saving the voltages to the database, regenerate the DCS scripts via the menu: Action -> Generate Recipe Scripts. Detailed instructions are here.

How to change the voltage for the DSO scan

At this point you should follow the instructions for doing a pedestal run. Note that you should also follow the instructions for uploading channel thresholds and masks to the database!

Start a new data taking run

Generally you can follow the instructions posted here. However, you will probably be requested to do a short run, so be sure to stop the run once it has gone long enough.

When the special run is complete, follow these same instructions to put the DAQ back into its nominal state. Currently, the voltage settings for warm and cold are, respectively, 2957 and 1533.

Previous Page Main Page What to do while on shift DAQ Trouble Shooting Guide