The software module for testing measurement transducers enables a CMC (For CMC 356 the ELT-1 hardware option is required) for manual or automatic testing of any measurement function, such as:
- Real power (single- or three-phase)
- Reactive power (single- or three-phase)
- Apparent power (single- or three-phase)
- Voltage (phase-to-ground, phase-to-phase)
- cos phi
- Phase angle (V-I, V-V, I-I)
- DC quantities (current, voltage, power)
- Signed average of currents
The module supports testing of the following types of characteristics:
- Symmetrical or non-symmetrical
The “manual test” mode is used, if a measurement transducer is to be re-adjusted. Every desired input quantity can be generated for the transducer. Furthermore, it is easy to switch between significant points of a characteristic, where the error of the transducer is shown at a certain input value.
An automatic test includes the sequential output of a pre-defined test point table, as well as the documentation and assessment of the results. Here, the test points represent the input value of the measurement transducer. In addition, the behavior at changing input voltage or frequency can be performed as an option.
The error of a transducer is determined by comparing the theoretical signal and the actually measured output signal. Relative, absolute and device errors are derived and graphically displayed in a diagram.
Measuring transducers for three-wire (Aaron circuit) as well as four-wire systems can be tested. Currents as well as voltages can be generated as pure sine signals or superimposed with harmonics or DC components. New generation transducers often no longer have classical mA or VDC output. They rather transmit the measured data via transfer protocol or/and visualize values at a display. The mode “open loop testing” supports testing this type of transducer.