Versions Compared

Old Version 4

changes.mady.by.user Brendan D. Oshea

Saved on

compared with

New Version Current

changes.mady.by.user Ariniello, Robert

Saved on

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

Procedure for checking the chiller load before turning on the SAGAs

  1. Ensure the S21 LCS cooling system has sufficient capacity for the SAGAs.
    1. The cooling system has sufficient capacity for the SAGA lasers if the current usage is at or below 29 28 kW 11 kW.
    2. Open the archiver (FACETHOME→Archive Viewer) and load (File→Open) ‘S21_LCS_SAGAs_July_2021.xml’ file to load the correct PVs for the S21 LCS chiller.
    3. Click the Plot button on the middle right of the panel.

Image Modified

  1. The black line is the ‘chiller load’ in kW. You will may have to adjust the range for chiller load to 9 to 17 kWusing the min/max fields above the plot. The black line should be below 11 28 kW when the SAGAs are off.
  2. The red line (the input water temp) should be < 77 degrees Fahrenheit77° F. It is usually at 63F 63° F or below.

Image Modified


Chiller system informationHow to check that the SAGAs are happy

If the red line is below 77 degrees ° F and the black line is below 17 33.25 kW, then the SAGAs are happychiller system is working as intended.

The chilled water system can handle a maximum heat load of 33.25 kW. If the heat input exceeds the chiller capacity, the input water temperature will continuously climb and exceed 77° F, at which point the lasers start getting unhappy. In particular the LCLS injector lasers will get unhappy and FACET will be asked to turn the SAGA lasers off. Each SAGA requires 2.5 kW of cooling capacity, 33.25 kW - 2*2.5 kW = 28.25 kW sets the maximum load that still has capacity for the SAGA lasers.

A side note, the regen requires 1.6 kW of cooling, but, since it is typically always on, its chiller load doesn't need to be taken into account during normal operation.