ATO/SP3 IoT Series

Split-core current transformer with high accuracy and low phase shift

ATO/SP3 IoT Series

ATO/SP3 IoT Series

Please find here the product page


Main characteristics:

  • Measurement of AC primary currents from 0 to 10A
  • Voltage output (ratio 225mV @ IPr)
  • Class accuracy 1 (voltage output) according to IEC 61869 standard
  • Compact
  • Self-powered
  • 10 mm diameter aperture
  • Frequency: 50/60 Hz


  • Split-core type
  • Easy mounting
  • Cable output: 1m
  • Operating range: -10°C to +55°C
  • Dimensions (ATO): 45.5 x 33.5 x 32 mm with a 10 mm sensing aperture
  • Rated insulation voltage 600V CATIII PD2, basic insulation

Standard compliance:

  • The products are CE certified EMC 2014/30/EU regarding their safety according to the European directive 2014/35/EU and tested according to the standards IEC 61010-1.
  • UL 508 (UR marking)
  • IEC 61869 for Instrument transformers performances


  • Fast clip-on mounting whilst cable is connected
  • Principal applications are in the field of energy consumption sub-metering and analysis, branch current monitoring, defective equipment detection and power quality control
  • Slot expected to fix the ATO on conductor with a cable tie
  • DIN rail adaptor (optional)
  • Bosch XDK110 compatible (not supplied)

Download Technical Articles: IoT remote energy monitoring using LEM Split-Core CT (ATO) following the IEC 61869-2 Smart Grid standard
Download Technical Articles: Smart Building energy disaggregation Submeter with LEM Split-core CT ATO