Michael Strauss: "Our fiber optic repeater can also be used in a mixed network of ASi-3 and ASi-5. It connects remote ASi-3 segments to this mixed system."

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AS-interface is characterized by the fact that data and power are transmitted on a 2-wire flat cable. Thanks to piercing technology, devices can be easily connected to the cable at any point. "With the AS-i fiber optic repeater, data and power supply are now separated from each other for the first time. This allows data to be transmitted over a distance of more than 3000 m via an optical fiber. This makes almost any network length possible," says ifm product manager Michael Strauss, describing the particular benefits of the new solution. "Especially in security technology, systems can be solved even more easily if all signals converge on one gateway."

Due to the optical transmission, there is no interference or grounding problems. This means that fiber optic transmission systems fundamentally eliminate the EMC risk. In addition, the fiber optic cable can be used for lightning protection and is insensitive to interference from EM radiation.

Systems with very large extensions can now also benefit from the specific AS-i advantages: "In open-cast mining, for example, safety elements such as rope pull switches or emergency stop buttons along the conveyor line can be wired with AS-i," says Strauss. In the process industry, where groups of sensors and actuators are distributed over long distances, the use of fiber optic repeaters further improves cost-effectiveness. As a side effect, the energy-free data transmission makes it possible to cross ATEX zones that would otherwise have to be bypassed over large areas.

The fiber optic repeaters are always used in pairs. AS-i signals, which are modulated onto the supply voltage, are converted into light signals on the transmitter side. The receiver transmits the data back to the next copper segment with the supply voltage. In this way, the optical fiber galvanically separates the network segments from each other.