Cryogenic (Sub-Ambient) Oven Control - HP 5890 Series II Plus Reference Manual

Temperature Control

Cryogenic (sub-ambient) oven control

Cryogenic (sub-ambient) oven control
Liquid N or liquid CO cryogenic options are for operation at
temperatures less than about 7 C above ambient. This is done through
operation of a valve which opens when coolant is demanded and closes
when the setpoint temperature is reached.
When you press
through a series of displays for choosing cryogenic options. These options
include CRYO for operation during the entire run, CRYO BLAST, for very
fast cool down between runs, and AMBIENT to regulate on and off times
to optimize coolant use.
Figure 3-3
Cryogenic options
The following figures show the oven temperature profile for a typical run,
showing the on and off times for CRYO and CRYO BLAST.
gold CRYO PARAM
ACTUAL
CRYO
ACTUAL
CRYO BLAST
ACTUAL
AMBIENT
CRYO PARAM CRYO PARAM
SETPOINT
For operation during runs at
ON
subambient temperatures.
SETPOINT
For very fast cool down
ON
between runs.
SETPOINT
Lets you regulate Cryo and
25
Cryo Blast on and off times to
optimize coolant use. Default is
25 C and need not be changed
unless
ambient differs by 10 .
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