Why do some SCADAR™ data loggers contain an external power supply?

Why do some SCADAR™ data loggers contain an external power supply?

Please refer to Section 4.2 of the SCADAR™ equipment technical manual and read section 4.2.5!  Understand the difference between the SCADAR™ data loggers internal source of energy (lithium batteries) and the featured sensors source of energy...


  • ALL SCADAR™ data loggers are powered using internal lithium batteries.
  • 'Some' SCADAR™ data loggers feature an external power supply.  When present, this is used to ONLY power the SCADAR™ data loggers sensor
  • If the sensor associated with the SCADAR™ data logger is NOT 4-20mA loop powered (PRESSURE, TEMPERATURE, CURRENT) there's sufficient energy in the SCADAR™ data loggers lithium batteries to power the sensor and consequently an external source of power is NOT provided or required
  • If the sensor associated with the SCADAR™ data logger IS 4-20mA loop powered (FLOW, DEWPOINT or 4-20mA GENERAL PURPOSE (GP) (optional in the case of GP data logger)) there's insufficient energy in the SCADAR™ data loggers lithium batteries to power the sensor and consequently an external source of power is supplied and necessary!
  • The use of an external power supply does NOT eliminate the use of or need for the SCADAR™ data loggers internal lithium batteries.  Always ensure that SCADAR™ data logger lithium batteries are 'healthy' prior to commencing any audit.
  • Simply put, the internal lithium batteries ALWAYS provide a source of energy for the SCADAR™ data logger!
  • The presence of a 4-20mA sensor will ALWAYS equal the need for the external power supply!
  • All SCADAR™ data logger and sensor assemblies that feature 4-20mA loop powered sensors are supplied with an external power supply
  • When featured and required, the SCADAR™ data logger sensor is powered via the SCADAR™ data logger assemblies power supply jack.  The SCADAR™ data logger and 4-20mA sensor assembly is pre-wired to route energy from the external source of power to the 4-20mA loop powered sensor
  • Users SHOULD NOT confuse the presence of the power supply jack at the SCADAR™ data logger having any other purpose than the routing of energy from an external power supply to the sensor that features and requires a source of 4-20mA loop power.  Simply put...  this is the only purpose of the SCADAR™ data loggers power supply jack!


For further guidance, refer to the SCADAR™ equipment technical manual.