Tel.: +36-20-344-1787, or E-mail: rapaskft@rapasuuhu


Power / Energy Meter Single Phase, RS485, Qeed QI-Power-485LV

The smallest energy meter of the world

50 A AC/DC current transformer / transducer and energy meter with RS485 MODBUS interface


is a Single-phase Power / Enegy meter / transducer for the measurement of DC/ACtrms current and voltage having an RS485 Modbus interface. Accessible mesured values through the RS485 Modbus are: Irms, Vrms, Watt, Var, Va, Vpk, Ipk, Frequency, Cos φ, Bidirectional Energy and THD. The QI-Power--485LV power/energy meter / transducer  is fully configurable through its RS485 interface. DIN rail mount design with galvanic isolation between inputs and output. 

Main features

  • TRMS Measure, THD available
  • Accuracy 0,5%
  • RS485 Modbus integrated
  • Bidirectional energy metering
  • Installable on DIN-rail in both directions
  • OEM’S design, low cost
  • Fully configurable by free interface software FACILE QI-POWER-485
  • Bootloader for updating firmware
  • Available measure register: MSW first LSW first or hundredth
  • Flash memory, data retention min. 4.5 years, typical 45 years
  • Minimum measurable current (cut off): 0 - 2560 mA
  • Minimum measurable power (cut off): 0 - 2560 W
  • Measurement speed: every 50 cycles or 1 s (faster) can be set with the FACILE software

USB/232-485 adapter (opcional accessory) can be used to connect the PC /laptop having USB port (FACILE software installed on it), to the RS485 bus for congurating the parameters of the QI-Power-485LV current transformer / power transducer


  • Measuring ranges:
    • Current: up to 50 A AC/DC
    • Voltage: up to 80 VAC or 100 VDC
  • Measurements: Irms, Vrms, Watt, Var, Va, Vpk, Ipk, Frequency, Cos φ, Bidirectional energy, THD, min and MAX of each measurement
  • Mesuring mode: TRMS or DC
  • Accuracy ()@25°C up to 200 Hz)
    • Voltage, Current, Active Power: ≤ 0,5% F.S.
    • Frequency: ±0,1 Hz
    • Energy: ±1% of reading
    • Vpeak, Ipeak: ±5% F.S.
  • Temperature coefficient: ≤ 200 ppm/°C
  • Crest factor 1,8 (at current measurement)
  • Working frequency: DC, 1...400 Hz
  • Ootput: RS485 Modbus RTU
  • Baud-Rate: 1.200... 115.200 baud
  • Power supply: 9... 30 Vdc, ≤1,3 W, protection against polarity reversal and overtemperature
  • Reference Standards: CE EN61000-6-4/2006 + A1 2011; EN64000-6-2/2005; EN61010-1/2010
  • Ovevoltage: Cat III up to 600V; Cat II up to 1000V
  • Insulation
    • 3 kV for bare wire of Current measurement
    • 4 kV for Voltage measure (reinforced insulation to power supply and serial output)
  • Protection index: IP20
  • Working temperature: -15… 65°C
  • Storage temperature: -40°C... 85°C
  • Humidity: 10… 90% RH not condensing
  • Altitude of use: up to 2000 m asl
  • Dimensions: 46,1 x 63 x 26,4 mm (terminal excluded)
  • Weight: 80 g
  • Removable terminals: 3,5 mm
  • DIP switch for address configuration
  • Mounting: screws or DIN rail clips (included) for vertical/horizontal mounting