Campbell CR850, Руководство оператора

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Section 7. Installation
7.1 Moisture Protection
When humidity tolerances are exceeded and condensation occurs, damage to
CR800 electronics can result. Effective humidity control is the responsibility of
the user.
Internal CR800 module moisture is controlled at the factory by sealing the module
with a packet of silica gel inside. The desiccant is replaced whenever the CR800
is repaired at Campbell Scientific. The module should not be opened by the user
except to replace the lithium coin cell providing back up power to the clock and
SRAM. Repeated disassembly of the CR800 will degrade the seal, leading to
potential moisture problems.
Adequate desiccant should be placed in the instrumentation enclosure to prevent
corrosion on the CR800 wiring panel.
7.2 Temperature Range
The CR800 is designed to operate reliably from -25 to +50°C (-40°C to +85°C,
optional) in non-condensing environments.
7.3 Enclosures
Illustrated in figure Enclosure
(p. 82)
is a typical use of an enclosure, which is
available from Campbell Scientific. This style of enclosure is classified as
NEMA 4X (watertight, dust-tight, corrosion-resistant, indoor and outdoor use).
Enclosures have back plates to which are mounted the CR800 datalogger and
associated peripherals. Back plates are perforated on one-inch centers with a grid
of square holes that are lined as needed with anchoring nylon inserts. The CR800
base has mounting holes (some datalogger models may be shipped with rubber
inserts in these holes) through which small screws are inserted into the nylon
achors. Remove rubber inserts, if any, to access the mounting holes. Screws and
nylon anchors are included in an enclosure supply kit included with the enclosure.
Refer to
Enclosures
(p. 544)
for a list of available enclosures.