Thin and flexible coils look to empower smart cities
LEM has upgraded its 'ART' Rogowski current sensor so that it measures current of up to 10,000A AC and beyond with class accuracy 0.5. The ART achieves IEC 61869 Class 0.5 accuracy without the need for additional components like resistors or potentiometers, which can drift over time.
In addition, the ART benefits from 'perfect loop' technology, a patented coil clasp that eliminates the inaccuracy caused by sensitivity to the position of the conductor inside the loop as well as providing an innovative, robust and fast 'twist and click' closure.
An internal shield is provided as standard to guard against external fields, improving accuracy and optimising performance for small current measurements.
The ART series provides the same ease of installation as existing split-core transformers, but with the benefits of being thinner and more flexible.
Whatever the chosen dimension - 50, 70, 125, 175, 200 and 300mm diameter for the aperture – the ART can be mounted quickly by simply clipping on to the cable to be measured. Contact with the cable is not necessary, and the ART ensures a high level of safety as well as providing a high rated insulation voltage (1000V Cat III PD2 - reinforced).
The ART also allows disconnection of the coil to be detected through the use of a security seal passed through a specially designed slot, making it useful when used with a meter. It can be used in applications requiring a protection degree up to IP 67.
This Class Accuracy 0.5 ART updated version completes the LEM City product solutions for the AC current measurement dedicated for future smart cities offering high quality solutions for measuring electrical parameters in smart grids and Industry 4.0.
Intelligent electricity network (smart grid) applications such as power generators, medium voltage/low voltage substations and sub-metering integrate more and more current sensors to ensure reliable integration of distributed renewable energy, energy storage, production and consumption. This leads to the implementation of more current sensors to allow control rooms to automate, to monitor remotely and share real-time data of equipment.
ART series current sensors are CE marked and conform to the IEC 61869 standard, as well as being covered by LEM’s five year warranty.