Campbell Scientific RF310, RF312, RF313 Narrowband Radios - Manual (Page 36)

Section 3. Radiotelemetry Network Components
3-14
Some solar panels are supplied with a connector. This connector must be
clipped off so the two wires can be inserted into the two terminal ports.
The red charge light is on when AC power or a solar panel is connected to the
PS12. If the input voltage is high enough, the battery will charge even when
the datalogger is on.
Switch the power to OFF before disconnecting or
connecting the power leads to the Wiring Panel. The
Wiring Panel and PS12LA are at power ground. If 12V is
shorted to either of these, excessive current will be drawn
until the thermal fuse opens.
The external port, labeled EXT, is not meant to be used with the PS12LA. The
primary power source is the charging source, and the secondary power source is
the internal lead acid battery. Connecting a lead acid battery to the external
source is the same as connecting two lead acid batteries in parallel, causing one
battery to drop voltage and the other to raise voltage. Alkaline batteries
connected to the external port would be charged by the charging source, which
can cause an explosion.
Never connect more than one battery to the PS12LA.
Monitor the power supply using datalogger Instruction 10. Users are strongly
advised to incorporate this instruction into their data acquisition programs to
keep track of the state of the power supply. If the system voltage level
consistently decreases through time, some element(s) of the charging system
has failed. Instruction 10 measures the voltage of the lead acid battery.
External power sources must be disconnected from the CR10 and charging
circuit in order to measure the actual lead acid battery voltage.
TABLE 3-6. PS12LA Battery and AC Transformer Specifications
Lead Acid Battery
Battery type Yuasa NA 7-12
Float life @ 25
°C
5 years typical
Capacity 7.0 Amp-hour
Shelf life, full charge Check twice yearly
Charge time, (AC Source) 40 hr. full charge 20 hr. 95% charge
AC Transformer
Input: 120V AC, 60 Hz
Isolated output: 18V AC @ 880 mA max.
3.4.3.3 PS512M Voltage Regulator with Null Modem Ports
The PS512M 12 Volt Lead Acid Power Supply with Charging Regulator and
Null Modem Ports is used when 5 Volts is needed to power external modems
besides the capabilities of the PS12LA. The PS512M supplies 5 Volts to pin 1
of the 9-pin null modem ports, otherwise the capabilities and functions are
identical to the PS12LA. A common use for the PS512M is in radiotelemetry
CAUTION
CAUTION