Versatile. Modern. Innovative.

Product solutions from MAGNETEC provide reliable success in the most varied types of application.

Current Measurements

Thanks to the sensors developed by MAGNETEC, AC currents and AC and DC residual currents can be measured while electrically insulated. MAGNETEC current sensors with cores made of the nanocrystalline alloy NANOPERM will be integrated in your application in such a way that the current in a line or cable can be measured extremely accurately with the passage of a coil through the sensor. The galvanically isolated current measurement is realized by a current transformer (CT) in AC applications and an RCD can detect AC and DC residual currents in your application.

Current Transformer for Energy Measurement

For the exact measurement of current, for example in smart meter applications, great demands are made of the current transformer (CT). In addition to their compact constructions, NANOPERM cores have high linearity and saturation induction, low losses and low temperature dependency. As a result, small phase and amplitude errors can be realized in order to ensure a high degree of accuracy. The products based on NANOPERM cores also have high thermal surge current capability and resistance, as a result of which they can be used very well in electricity networks. High permeability up to the upper kHz range makes the use of NANOPERM materials indispensable in (power) electronics to detect higher frequencies. In addition, increasing numbers of consumers are fed/operated with direct current, as a result of which DC-tolerance is required for electricity meters. The requirements of the current standards can be easily met with NANOPERM cores.

Residual Current Sensors Sensitive to Universal Current

Royer oscillators are often used in order to be able to ensure accurate AC/DC residual current detection, for example in car charging cables, wallboxes (domestic), charging stations (public) or in the vehicle itself. In this concept, the core is run in saturation, as a result of which the conducting phase of a transistor changes and the core is saturated in the opposite direction. Thanks to the high permeability of NANOPERM cores, DC currents in the milliampere range can be detected in every detail. Thanks to good temperature stability, the products can be used perfectly in changing ambient conditions. With the help of NANOPERM cores, therefore, even residual current transformers sensitive to universal current can be realized, as a result of which the requirements of IEC 62752:2016, IEC 62955:2018, UL2231 are met without using an expensive FI Type B. Our clients can buy MAGNETEC residual current transformers as a passive component for the greatest possible design sovereignty or as an active sensor. We can do this together with our EMS partner of many years’ standing.

Residual Current Protective Switch

A residual current protective switch – FI switch for short – does not protect the cables against surges or short circuits like a circuit breaker, for example, but rather is used to protect people and/or as fire protection. Two- and four-pole versions are standard.
FI switches with a tripping current of 30mA is used, in other words, in the event tripping, max. 30mA flow through the human body within a few milliseconds.

The central element of the FI switch is a residual current transformer that triggers a mechanical relay downstream. All active cables and the neutral conductor are fed through the residual current transformer. Normally, the total of all the current flowing over the outer conductor and the current returning over the neutral conductor must be compensated = current total zero. If this is not the case, leakage current must flow to the ground obviously within the installation. It is irrelevant whether this leakage current flows away directly via the protective conductor or, for example, via the human body towards the ground; in any case, the FI switch trips when the tripping current is reached. For more than 30 years, MAGNETEC has been producing and supplying millions of residual current transformers and modules for FI switches of all well-known manufacturers and has thus reliably and sustainably helped to protect life and limb, as well as equipment, against damage.

How may we help you?

Use our contact form for any questions associated with our extensive range of products and services. We will pass your inquiry directly on to your personal project advisor and will contact you soon!

We’re looking forward to hearing from you


Magnetec Business Unit: