In the CR300 User Manual is written "Voltage on a SW12 terminal will change with data logger supply voltage." I thought this means the Charge Voltage.
On my CR300, SW12 is not equal to the Charge Voltage, but to the Battery voltage. Can someone confirm that this is a normal behaviour? Will say "datalogger supply voltage" means battery voltage.
You are correct, this is normal behaiour. The SW12 connection uses the "Battery Voltage" and the datalogger supply voltage is the battery connection in this case.