Miscellaneous
Lasair II Particle Counter Operations Manual
Page C-7
Data Buffering
If the computer system goes down while data are being downloaded from the Lasair
II particle counter, it would be quite easy to lose these data. As protection, the
particle counter automatically retransmits up to 3000 recent data samples when it is
configured to Facility Net, IF:
•
The Lasair II particle counter was connected when the computer system went
down, AND
•
The Lasair II particle counter is not powered off before Facility Net comes
back up.
These data are stored in a separate buffer and are not affected by emptying the
historical data file.
Assigning Location Names
Some forethought is required when designing a Facility Net system. Each
instrument's address may be associated with up to 256 locations. For smaller
systems it may be adequate to use a single address for all Lasair II particle counters.
For larger systems, multiple addresses may be required. The TCP/IP protocol uses
both the location name and the instrument address as key fields when saving the
data.
The TCP/IP remote download function in Facility Net can substitute the user-
defined instrument name instead of using the TCP/IP address. This allows different
addresses for each Lasair II particle counter, which is good networking practice. If
the instrument name matches the name previously configured, pop-up dialog
queries the user to move the configuration from the previous TCP/IP address to the
new one.
