Campbell Scientific CR200/CR200X-series Dataloggers - Manual (Page 45)

Section 3. Overview
3.1.8.2 Protection from Voltage Transients
Read More! See Grounding (p. 55).
The CR200(X) 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 CR200(X).
3.1.8.3 Calibration
Read More! See Self-Calibration p. 41.
The CR200(X) uses an internal voltage reference to routinely calibrate itself.
3.1.8.4 Replacing the Internal Battery
Caution Fire, explosion, and severe burn hazard! Misuse or improper
installation of the lithium battery can cause severe injury. Do not
recharge, disassemble, heat above 100°C (212°F), solder directly to the
cell, incinerate, or expose contents to water. Dispose of spent lithium
batteries properly.
The CR200(X) contains a lithium battery that operates the clock and SRAM
when the CR200(X) is not powered. The CR200(X) does not draw power from
the lithium battery while it is powered by an external source. In a CR200(X)
stored at room temperature, the lithium battery should last approximately 5
years (less at temperature extremes). Where the CR200(X) is powered most or
all of the time the lithium cell should last much longer.
The internal lithium battery must be replaced periodically. Factory replacement
is recommended. Contact Campbell Scientific to obtain an RMA prior to
shipping the CR200(X).
If the lithium cell is removed or allowed to discharge below the safe level, the
CR200(X) will still operate correctly while powered. Without the lithium
battery, the clock will reset and data is lost when power is removed.
A replacement lithium battery can be purchased from Campbell (part number
15598). TABLE. CR200(X) Lithium Battery Specifications p. 33 lists the
specifications of the battery. However, Campbell Scientific recommends that the
battery be replaced at the factory.
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