The power quality evaluation according to standard EN 50160 is carried out on all voltage levels in different ways and therefore it depends on the reasons that motivate the user to use it. The quality of electricity is mainly related to the quality of the voltage, but many meters also measure the currents, creating a combined instrument for measuring of quality, power and energy (electricity meter). Quality can be measured for orientation purposes, here are usually S-class meters good enough. In cases of measurements at important distribution sites, class A quality meters with higher accuracy can be used.
During a measuring with ppower quality meters, different network parameters are detected to indicate its status, and if something is wrong, then the causes of poor quality are searched. The most frequently measured parameters are:
- U, I, P, Q, S,
- PF, cos φ,
- symmetric components,
- total harmonic distortion,
- individual harmonics,
- active energy, reactive energy.
At the time of renewable energy sources, the measurement of electricity quality is interesting for both suppliers and customers, as one side often alternates both roles. Other usage of power quality meters is in large objects with a high number of users. In case of sensitive devices destruction, it is also possible to demonstrate by monitoring of network quality parameters, whether the cause was poor quality of electricity in the network and what could be its source.
You can find several S and A class power quality meters in our offer that are used in substations, secondary substations and end-user buildings. The specific types can be recommended by our sales professionals.
If the power quality meters are located in power distribution objects, they communicate usually with RTU systems. RTUs concentrate the data and send it to the dispatching center or store it in special databases for subsequent evaluation. A special SW is used for evaluation, or some information can be automatically reported by email.