Burping the Solar FTS

"Burping" the Solar FTS


Burping the Solar FTS is a process whereby any air that has gotten trapped in the oil system is released in a way that prevents oil from being 'splattered' onto the optics. This process should be followed whenever the FTS tank has been up to atmospheric pressure and before the oil system is turned on.
  1. Locate the bypass switch. On the Oil system rack, below the vacuum pump electronics, pull out the chassis with the B/S cable connector on it. In the chassis you will find 2 push buttons and a toggle switch.
  2. Turn the toggle switch to the ENABLE position. Now, push the button labeled BYPASS ON and return the toggle to the DISABLE position. This will allow the oil to circulate in the bottom of the tank only, keeping the oil and any 'splatters' farther from the optics.
  3. Close off the vacuum pumps from the tank (rough & hi vac switches up).
  4. Turn on the oil pump by powering up the oil chassis then holding in the green ON button. Watching the tank pressure gauge, switch off the oil pump power as soon as the tank pressure is seen to rise.
  5. Reopen the vacuum pumps to the tank.
  6. Wait a few minute before repeating steps 3 - 5 until no pressure rise can be seen.
  7. Switch the toggle switch again to the ENABLE position and press the No Bypass button. Oil will now flow up to the bearing when the oil pump is engaged. At this point the FTS Control Rack must be powered up!
  8. Repeat steps 3 - 5 until pressure no longer goes up when oil is introduced to the tank. Keep an eye on the oil pressure gauge on the side of the tank for the first 15 minutes that the oil system is turned on. If the pressure begins to drop, immediately switch off the oil pump and wait a couple of minutes before restarting it. This would indicate that the oil pump has gotten an air bubble in it and has started to 'cavitate'. Turning off the pump should allow the air rise out of the pump and should then work properly.

After the 'burping' is complete, set the laser at 'A' port and align it backward through the FTS. Install the movable aperture at the input and position the aperture so that the 'bulls eye' pattern is centered. Check this at both ends of travel and average the adjustment if necessary.

As a final check, mount a detector, put up a light source, find the central fringe (WLF) and try a short scan or SNAP.


Return to the FTS Notes book.