CR1000 Manual - Campbell Scientific

Section 5. System Overview
5.1.11 Maintenance
Read More! See Maintenance (p. 417).
With reasonable care, the CR1000 should give many years of reliable service.
5.1.11.1 Protection from Water
The CR1000 and most of its peripherals must be protected from moisture.
Moisture in the electronics will seriously damage, and probably render unrepairable,
the CR1000. 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 CR1000 in a weather-tight enclosure with
desiccant and elevating the enclosure above the ground. The CR1000 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. 566) for information on available weather-tight enclosures.
5.1.11.2 Protection from Voltage Transients
5.1.11.3 Calibration
5.1.11.4 Internal Battery
Read More! See Grounding (p. 86).
The CR1000 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 CR1000. Refer to the appendix Transient Voltage Suppressors for
information on available surge-protection devices.
Read More! See Self-Calibration (p. 289).
The CR1000 uses an internal voltage reference to routinely calibrate itself.
Campbell Scientific recommends factory recalibration every two years. If
calibration services are required, refer to the section entitled Assistance (p. 5) at the
front of this manual.
Caution Misuse or improper installation of the lithium battery can cause severe
injury. Fire, explosion, and severe burns can result! Do not recharge, disassemble,
heat above 100°C (212°F), solder directly to the cell, incinerate, nor expose
contents to water. Dispose of spent lithium batteries properly.
The CR1000 contains a lithium battery that operates the clock and SRAM when
the CR1000 is not externally powered. In a CR1000 stored at room temperature,
the lithium battery should last approximately 3 years (less at temperature
extremes). If the CR1000 is continuously powered by 12 Vdc, the lithium cell
should last much longer. Lithium battery voltage can be monitored from the
CR1000 Status table. Operating range of the battery is approximately 2.7 to 3.6
Vdc. Replace the battery as directed in Replacing the Internal Battery (p. 417) when
the voltage is below 2.7 Vdc.
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