Power input

The data logger requires a power supply. It can receive power from a variety of sources, operate for several months on non-rechargeable batteries, and supply power to many sensors and devices. The data logger operates with external power connected to the green POWER IN port on the face of the wiring panel Wiring panel and terminal functions. The positive power wire connects to the 12V terminal. The negative wire connects to G. The power terminals are internally protected against polarity reversal and high voltage transients. If the voltage on the POWER IN terminals exceeds 19 V, power is shut off to certain parts of the data logger to prevent damaging connected sensors or peripherals.

The primary power source, which is often a transformer, power converter, or solar panel, connects to the charging regulator, as does a nominal 12 VDC sealed rechargeable battery. A third connection connects the charging regulator to the 12V and G terminals of the POWER IN port. ClosedUPSUninterruptible Power Supply. A UPS can be constructed for most data logger applications using ac line power, a solar panel, an ac/ac or ac/dc wall adapter, a charge controller, and a rechargeable battery. is often the best power source for long-term installations. If external alkaline power is used, the alkaline battery pack is connected directly to the POWER IN port. External UPS consists of a primary-power source, a charging regulator external to the data logger, and an external battery.


Sustained input voltages in excess of those listed in the Power requirements, 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. Troubleshooting power supplies

The CR1000X can receive power via the POWER IN port as well as 5 VDC via a USB connection. If both POWER IN and USB are connected, 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, SW12, and 5V 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 ( USB) include sending programs, adjusting data logger settings, and making some measurements.


The Status field Battery value and the destination variable from the Battery() instruction (often called batt_volt in the Public table) reference the external battery voltage. For information about the internal battery, see Internal battery.

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 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.

Power LED indicator

When the data logger is powered, the Power LED will turn on according to power and program states:

  • Off: No power, no program running.
  • 1 flash every 10 seconds: Powered from BAT, program running.
  • 2 flashes every 10 seconds: Powered from CHG, program running.
  • 3 flashes every 10 seconds: Powered via USB, program running.
  • Always on: Powered, no program running.