Campbell Scientific CR1000KD CR800 and CR850 Measurement and Control Systems - Page 81

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. 81