Campbell Scientific CR5000 Measurement and Control Module - Manual (Page 36)

Section 1. Installation and Maintenance
1-12
FIGURE 1.9-2. Power Switching without Relay
1.10 Maintenance
The CR5000 power supplies require a minimum of routine maintenance.
When not in use, the rechargeable supply should be stored in a cool, dry
environment with the AC charger active.
1.10.1 Desiccant
The CR5000 is shipped with desiccant to reduce humidity. Desiccant should
be changed periodically. To prevent corrosion in uncontrolled or condensing
atmospheres, the CR5000 must be placed inside a weather tight instrument
enclosure with desiccant. 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.
1.10.2 Replacing the Internal Battery
Misuse of the lithium battery or installing it improperly can
cause severe injury. Fire, explosion, and severe burn
hazard! Do not recharge, disassemble, heat above 100°C
(212°F), solder directly to the cell, incinerate, nor expose
contents to water.
The CR5000 contains a lithium battery that operates the clock and SRAM
when the CR5000 is not powered. The CR5000 does not draw any power from
the lithium battery while it is powered by a 12 VDC supply. In a CR5000
stored at room temperature, the lithium battery should last approximately 10
years (less at temperature extremes). Where the CR5000 is powered most or
all of the time the lithium cell should last much longer.
CAUTION