Operator's guide
•
The recycle option causes the DCM to overwrite the oldest data on the
hard disk with incoming data. This way, the end point of the stored data
is known (it always includes the most recent block of data), but the start
point depends on the disk capacity.
disk.writeinterval : This setting alters how frequently the DCM will write data
to the hard disk. There are four manual timescales available: 1 hour, 4 hours, 1
day, or 1 week. There is also an automatic setting available, in which data will
be written out to the hard disk whenever the DCM's internal memory nears
capcity. (See
Chapter 6, “Inside the DCM”
for details of the algorithm used.) If
you choose one of the manual timescales for this option and the DCM runs out
of internal memory, you may lose data: as a result, it is recommended that you
leave this setting on automatic.
disk.heater : A heater is provided in the internal enclosure of the DCM to bring
the on-board hard disk up to operating temperature when required. If you are
using an on-board hard disk, you should set this option to automatic and choose
a suitable operating temperature below. If you are not using an internal hard
disk, you should disable the heater by setting this option to off.
disk.temperature : The operating temperature of the on-board hard disk, in
degrees Celsius. If you have set the internal heating to automatic, you should
enter a suitable operating temperature here. The hard disk will not function
properly below 0°C. With the heater active, the DCM is designed to operate in
ambient temperatures up to 40 degrees below zero.
4.3 Serial port configuration
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