Campbell CR850, Руководство оператора

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Section 5. System Overview
75
One use of file encryption may be to secure proprietary code but make it available
for copying.
5.1.10.5 Communications Encryption
PakBus is the CR800 root communication protocol. By encrypting certain
portions of PakBus communications, a high level of security is given to
datalogger communications. See
PakBus Encryption
(p. 346)
for more information.
5.1.10.6 Hiding Files
The option to hide CRBasic program files provides a means, apart from or in
conjunction with file encryption, of securing proprietary code, prevent it from
being copied, or making it tamper resistant. .CR<X> files, or files specified by
the
Include() instruction, can be hidden using the FileHide() instruction. The
CR800 can locate and use hidden files on the fly, but a listing of the file or the file
name are not available for viewing. See
File Management
(p. 324)
for more
information.
5.1.10.7 Signatures
Recording and monitoring system and program signatures are important
components of a security scheme. Read more about use of signatures in
System
Signatures
(p. 150).
5.1.11 Maintenance
Read More! See Maintenance
(p. 397).
With reasonable care, the CR800 should give many years of reliable service.
5.1.11.1 Protection from Water
The CR800 and most of its peripherals must be protected from moisture.
Moisture in the electronics will seriously damage, and probably render un-
repairable, the CR800. Water can come from flooding or sprinkler irrigation, but
most often comes as condensation. In most cases, protection from water is as
easily accomplished as placing the CR800 in a weather-tight enclosure with
desiccant and elevating the enclosure above the ground. The CR800 is shipped
with desiccant to reduce humidity. Desiccant should be changed periodically. Do
not completely seal the enclosure if lead acid batteries are present; hydrogen gas
generated by the batteries may build up to an explosive concentration. Refer to
Enclosures
(p. 544)
for information on available weather-tight enclosures.
5.1.11.2 Protection from Voltage Transients
Read More! See Grounding
(p. 86).
The CR800 must be grounded to minimize the risk of damage by voltage
transients associated with power surges and lightning-induced transients. Earth
grounding is required to form a complete circuit for voltage-clamping devices
internal to the CR800. Refer to the appendix Transient Voltage Suppressors
for
information on available surge-protection devices.