Troubleshooting guide

III.Nightly Startup Tasks

A. FLAMINGOS Setup

We recommend that you carry out the following procedures prior to each night's observing.

1. Restart all daemons, temperature logging and temperature plotting windows. Please see the notes at the end

of the previous section. The daemons should all be Quit (not Closed, as this just minimizes them), and

initflam.pl immediately re-run, in order to restart the daemons.

2. Fill Both Dewars. Observing with FLAMINGOS at the 2.1-m is very much a do-it-yourself operation. In

addition to running the telescope and instrument, the observer is responsible for keeping the two instrument

dewars full of liquid nitrogen (LN

), so that they stay cold continuously. You should receive sufficient

instruction on this procedure during your startup night at the telescope. If you still have questions, or are

uncomfortable with the procedure, please contact the observatory staff for more assistance.

• Both the Camera dewar (the big one on the bottom) and the MOS dewar (the one on the top) need to

be filled with liquid nitrogen at the start of every night before you can observe.

• The MOS dewar also needs to be filled at the end of every night.

CAUTION: The vent of the MOS dewar is about face-level in height. Do not stand close enough to the

vent such that liquid nitrogen can splash you in the face!

Fill the main dewar first and then the MOS dewar using the following procedure, which takes ~15 minutes.

• Check the pressure and fill gauges on the big storage dewar. The pressure should be ~20 psi and the

tank should be more than 1/3 full. If this is not the case, make sure to send a mountain service request

so that the KPNO elves will come and refill the tank before it gets too low. Also, note that you should

give the tank a shake prior to reading the liquid level, as the gauge can get stuck and read too high.

• Remove the small brass cap at the inlet port on the LN

manifold, and connect the fill line from the

storage dewar. Use the crescent wrench to gently snug the fitting. Do not overtighten.

• Turn the lower silver valve knob on the manifold counterclockwise to open; this knob controls the

flow of LN

to the Camera dewar, while the upper valve is for the MOS dewar.

• Then open the valve on the storage dewar SLIGHTLY, and let the line cool. When you open the valve

you should hear a whooshing sound from the dewar, and see some initial boiloff.

• When the whooshing stops or changes and/or the fill line looks good and cold, open the valve on the

storage dewar all of the way. The dewar is full when liquid is vigorously pouring out of the vent (a

solid stream, not a trickle) on the South side of the instrument.

• Once the Camera dewar is full, use the Polar gloves on the work table and close the bottom valve on

the manifold. When closing either of these valves, just barely snug them up − they do not need to be

tight.

• Now slowly open the upper silver valve on the manifold until it is open all of the way. The MOS

dewar may spit quite vigorously at first, but it really is not full. Give it several minutes, after which a

solid stream of LN

should be flowing out of the vent. CAUTION: The vent of the MOS dewar is

FLAMINGOS@2.1-m, Ver. 2.39, 2011 May 13 Page 11 of 46