Current and voltage transmitters are available in two versions:
first for arithmetic mean (calibration for sinusoidal quantities, form factor = 1.11) and
second for RMS measurements in distorted wave forms (AC coupling).
For power measurements, the measurement is always carried out up to approx. 16. Harmonics with the correct value. For commercially available cos phi converters, which only evaluate the difference between the zero crossings, care must be taken that the harmonics do not result in any additional zero crossings. More suitable here are converters which form the quotient of P w / P s, thus e.g. Multi-message (DME4xx, M563). Frequency converters are usually equipped with input filters that only evaluate the frequency.
Are your transmitters also suitable for 690V networks?
For measurement in 690V networks Preferably use 530 series instruments and DME4 .. multi-message converters.
What is the input voltage (rated voltage) for power converters in the 3-phase network?
In 3-phase networks, the input voltage (rated voltage) is generally the one chained Voltage (voltage between two phases). For measurements in 690 V networks, it is preferable to use devices of the 530 series and the DME4 .. multi-message converters.
How to re-calibrate power meters?
Previous analog devices must be re-calibrated at the factory.
Series 530 devices can be re-calibrated on site with little effort in terms of measurement within the range specified by the calibration factor (see operating instructions). Multi-measurement converters (DME4xx, M563) can be over-calibrated on site with the required software.
Ripple Control Frequencies (-signal) are superimposed as voltage signals on the phase voltage, changing the RMS value of that voltage. Effectively correct measuring transducers thus evaluate this voltage increase as a measuring signal and thus change the output signal by the amount of the influence of the ripple control frequency. Remedy occasionally special interpretations with appropriate filters.