The network isolator is used in copper-carried network connections (Ethernet) to protect a device connected to the network from external voltages of unknown origin. Such unwanted voltages can be caused by installation errors, switching operations, electrostatic discharges, potential differences or lightning strikes.

Furthermore, network isolators eliminate interfering low-frequency signal components. In particular, problems caused by network hum can be avoided by using network isolators. Network isolators were originally developed for medical, but are also used in other technical areas.

The network isolator transmits high-frequency alternating voltages according to the principle of electromagnetic induction in the frequency band used for data transmission.

Due to this transmission principle, it does not require a power supply. Installation of drivers is not required.

The task of a network isolator is to prevent any galvanic (= electrically conductive) connection between the connected devices. Therefore, in addition to the data lines, the cable shield is also galvanically isolated.

Application Areas

• Medical electrical equipment and systems where patients must be protected from leakage currents.
• Applications where valuable equipment or equipment requiring special protection is to be protected from hum and overvoltages from the network periphery.
• Electrical measuring and monitoring equipment which is to be protected against external and interference voltages.
• Computer systems that are galvanically connected to each other over long distances via Ethernet cabling and where potential equalization currents are to be prevented.
• Audio applications in which the transmission of low-frequency alternating voltages (mains hum) via the network connection is to be reduced to an imperceptible level.