*'''STE3/STE4''' has its own blue '''instrument Merlin crate''' mounted to the cylindrical dewar. There is a red reset button on the side of the crate that should be pressed if the instrument control software hangs, crashes or reports a "Merlin error". There is no need for observers to fill the dewar with liquid nitrogen; this is done by technicians in the morning and afternoon.
* '''SHOC''' does not require liquid nitrogen; it is peltier-cooled. It has no Merlin crate. The control PC ("shocnawe" or "shocndisbelief" ) is mounted in a crate below the primary mirror cell.
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