the voltage again equals or exceeds the lower limit. A second supply or charge regulator can be
provided to prevent measurement lapses during vehicle starting.
In vehicle applications, the earth ground lug should be firmly attached to the vehicle chassis with
12 AWG wire or larger.
2.1.2 Power LED indicator
When the data logger is powered, the Power LED will turn on according to power and program
states:
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Off: No power, no program running.
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1 flash every 10 seconds: Powered from BAT, program running.
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2 flashes every 10 seconds: Powered from CHG, program running.
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3 flashes every 10 seconds: Powered via USB, program running.
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Always on: Powered, no program running.
2.2 Power output
The data logger can be used as a power source for sensors and peripherals. Take precautions to
prevent damage to sensors or peripherals from over- or under-voltage conditions, and to
minimize errors. Additionally, exceeding current limits causes voltage output to become
unstable. Voltage should stabilize once current is again reduced to within stated limits. The
following are available:
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12V: unregulated nominal 12 VDC. This supply closely tracks the primary data logger supply
voltage; so, it may rise above or drop below the power requirement of the sensor or
peripheral. Precautions should be taken to minimize the error associated with the
measurement of underpowered sensors.
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SW12: program-controlled, switched 12 VDC terminals. It is often used to power devices
such as sensors that require 12 VDC during measurement. Voltage on a SW12 terminal will
change with data logger supply voltage. CRBasic instruction
SW12()
controls the SW12
terminal. See the CRBasic Editor help for detailed instruction information and program
examples:
https://help.campbellsci.com/crbasic/cr6/.
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CS I/O port: used to communicate with and often supply power to Campbell Scientific
peripheral devices.
CAUTION:
Voltage levels at the 12V and switched SW12 terminals, and pin 8 on the CS I/O port, are tied
closely to the voltage levels of the main power supply. Therefore, if the power received at the
POWER IN 12V and G terminals is 16 VDC, the 12V and SW12 terminals and pin 8 on the CS
2. Wiring panel and terminal functions
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