COM5003 | 3 Phase Reference Standard | ZERA/Powermetrix
The COM5003:
3 Phase Reference Standard
Accuracy 0.005%
Full NIST Traceability
Highest Accuracy in Its Class
Excellent Long-Term Stability

The COM5003 Reference Standard is part of the Powermetrix/ZERA high precision measuring instrument series. With the highest accuracy of 0.005 % (50 ppm), the COM5003 presents its new innovative digital technology and extended features for measurement. As a primary standard, the COM5003 is designed for testing electric revenue meters as well as single- or three-phase power and energy meter testing systems. This precise technology is especially useful in metrological institutes, official utility lab applications, and other environments for energy suppliers or manufacturers of electric meters and designed for integration of existing systems. All operation, measurements and data visualizations can be viewed using the COM5003’s simple user interface and 9“ touchscreen.


  • Actual value measurement
  • Vectorial display
  • Curve display
  • Harmonic measurement
  • Error measurement
  • Reference measurement
  • Power measurement at alternating energy direction

Actual value display COM5003 displays the current measured data in the actual value menu. Measured values are updated permanently. The parameters of the three-phase power system are displayed as averages values with adjustable integration time.

Vectorial display The measured values for current, voltage and phase angle can be shown as diagram according to IEC 387 or DIN 410.

Curve display The measured values of voltage and currents can be displayed in different ways. The user can choose between display as curves with indication of individual values and harmonic displaying with individual distortion values.

Harmonic measurement Harmonic measurement allows to measure harmonics in voltage and current circuit up to the 40th harmonic. The measured harmonics can be shown as table or bar chart.

Power measurement The power measurement allows to measure active, reactive and apparent power per phase and in total in measurement mode 2-wire, 3-wire or 4-wire.

Error measurement Static and electromechanical power meters as well as all kind of measuring instruments with power proportional frequency output can be tested in the menu “Error measurement”. The user can select between scanning head input or frequency input. The result will be shown in % with max. five decimal digits.

Reference measurement The reference measurement enables comparing an external DC voltage standard with the internal reference. For this purpose, the external standard will be connected with COM5003 via two separate inputs.

Power measurement at alternating energy direction CED power measurement determines the active power at alternating energy direction. CED means Change Energy Direction. The total power measurement value will be displayed as well as the part of positive and negative active power by using a predefined period interval (5 – 5000) and a time interval (1 – 100 s).