Dx-Power: Non-contact power measurements on vehicles

The power transmitted during actual driving is an important parameter for quantifying the efficiency of drivetrains. The driving power is calculated from the torque and speed of the shaft. The Dx-Power system makes mechanical power measurements on axles and shafts as simple as child's play. The system does not require an additional stator or reference point. The sensor unit (Dx-SCT) is mounted directly on the vehicle axle using a half-shell housing. There it records the torque (via strain gauges) and the speed via an integrated rpm sensor. The measured data are telemetrically transmitted to the Dx receiver unit (RCI) inside the vehicle. The receiver unit calculates the synchronous values of the two signals in real time according to the formula Power = Torque x Speed and displays all values in physical amounts.

Winner of the messtec + sensor masters award

At the messtec + sensor masters 2018 trade show, the Dx-Power system took first place in the sensor category and won the coveted messtec + sensor masters award. It was recognized as an innovative system for non-contact power measurements on vehicles that does not require any additional mechanical connection for rotation angle detection.

Original shaft is retained

The Dx-Power sensors are mounted in half-shell housings, which are individually attached to the shafts. The housings are also available in a waterproof version and contain all the necessary elements:

  • Dx-Power sensors
  • Dx transmitter unit and
  • Secondary winding for inductive power supply

Thanks to the flexible and easy to assemble housing concept, the original shaft can be retained and does not need to be shortened, adjusted or replaced. Set-up times are short and enable more reliable results with serial components.

Synchronous acquisition of up to four axles

The Dx telemetry system can work with up to four Dx-Power sensors and synchronously acquire the measured values from all four drive wheels or Cardan shafts. The data appear in real time and can be picked up and processed via CAN, Ethernet or analog.

Technical data

Maximum RPM±7200 1/min
Accuracy< 0.5 % at 0 °C to 50 °C
Signal frequency16 Hz (others on request)
Temperature range-20 °C to +65 °C
Torque measurementStrain gauge
Dx-Telemetry Transmitter Unit (SCT)
Transmission frequencyDx: 13 13 frequencies in the 868-MHz-Band
Dx-HT: 17 frequencies in the 2.4-GHz-Band
Sampling rateMax. 4.6/5.0 kHz per channel (868-MHz-/2.4-GHz-Band)
Resolution16 bit
Synchronized measurementsUp to 4 Dx-Power (4 shafts)
Ingress protection ratingIP 68
Power voltageBattery with 40 h operation time
Transmission powerMax. 10 dBm
Dx-Telemetry Receiver Unit (RCI)
Antenna inputs2 independent receivers in diversity mode
Display2.83 inch color display, 320 x 240 px
Auto-zeroRemote controllable
CAN interfaceCAN 2.0b acc. to ISO 11898, max. 1 MBaud
Analog output6 BNC sockets
ConfigurationUp to 4 Dx-Power
Power voltage9-36 Volt DC
Temperature range-20 °C to +65 °C
DimensionsApprox. 170 x 130 x 53 mm (without antenna)
WeightApprox. 0.8 kg

imc Test & Measurement is an Axiometrix Solutions company.