Vaisala WXT520 - Manual (Page 55)

Chapter 5 _______________________________________________ Wiring and Power Management
VAISALA_______________________________________________________________________ 53
NOTE If Heating function is enabled, SDI-12 Native mode consumes the
same as ASCII RS-232 mode.
When heating is on (or temperature is such it should be on), some
0.08 mA additional current is drawn from the operational power
supply.
NOTE While in Service mode and/or while supplied through the Service port
the WXT520 consumes 0.3 ... 0.6 mA more than in normal mode,
when supplied through the Main port (M12 connector or screw
terminals). When supplied through the Service port the minimum
voltage level for reliable operation is 6V. This can also be seen in the
supply voltage reading of the Supervisor message - the Vs value is 1V
lower than the actual input voltage.