WARNING:
Sustained input voltages in excess of 32 VDC on CHG or BAT terminals can damage the
transient voltage suppression.
Ensure that power supply components match the specifications of the device to which they are
connected. When connecting power, switch off the power supply, insert the connector, then turn
the power supply on. See
Troubleshooting power supplies
(p. 136) for more information.
Following is a list of CR6 power input terminals and the respective power types supported.
l
BAT terminals: Voltage input is 10 to 18 VDC. This connection uses the least current since
the internal data logger charging circuit is bypassed. If the voltage on the BAT terminals
exceeds 19 VDC, power is shut off to certain parts of the data logger to prevent damaging
connected sensors or peripherals.
l
CHG terminals: Voltage input range is 16 to 32 VDC. Connect a primary power source, such
as a solar panel or VAC-to-VDC transformer, to CHG. The voltage applied to CHG terminals
must be at least 0.3 V higher than that needed to charge a connected battery. When within
the 16 to 32 VDC range, it will be regulated to the optimal charge voltage for a lead acid
battery at the current data logger temperature, with a maximum voltage of approximately
15 VDC. A battery need not be connected to the BAT terminals to supply power to the data
logger through the CHG terminals. The onboard charging regulator is designed for
efficiently charging lead-acid batteries. It will not charge lithium or alkaline batteries.
l
USB port: 5 VDC via USB connection. If power is also provided with BAT or CHG, power will
be supplied by whichever has the highest voltage. If USB is the only power source, then the
CS I/O port and the 12V and SW12 terminals will not be operational. When powered by
USB (no other power supplies connected) Status field Battery = 0. Functions that will be
active with a 5 VDC source include sending programs, adjusting data logger settings, and
making some measurements.
NOTE:
The Status field Battery value and the destination variable from the
Battery()
instruction
(often called
batt_volt
or
BattV
) in the Public table reference the external battery
voltage. For information about the internal battery, see
2.1.1 Powering a data logger with a vehicle
If a data logger is powered by a motor-vehicle power supply, a second power supply may be
needed. When starting the motor of the vehicle, battery voltage often drops below the voltage
required for data logger operation. This may cause the data logger to stop measurements until
2. Wiring panel and terminal functions
9
