Signalling instead of switching – Residual current monitoring in earthed systems

Continuous monitoring

Periodic testing and monitoring of electrical installations and equipment is time-consuming and expensive. Here, continuous residual current monitoring for earthed power supplies (TN/TT systems) offers a time and cost-saving alternative. With this method, the electrical installation is continuously monitored for residual currents or fault currents as required by the relevant standards. For this purpose, earthed installations (TN-S systems) are equipped with a selective system for residual current monitoring (RCM).

Since the residual current is an image of the insulation resistance, residual current monitoring systems (RCMS) can continuously detect a selective insulation deterioration in stationary electrical installations. This deterioration leads to a measurable change in the residual current of the installation, which may result in critical changes in the system. RCMS not only detect fault currents in the development phase, overloading of N conductors are also indicated at an early stage.This significantly reduces the risk of fire. The operator is conveniently informed by an alarm message, e.g. via e-mail.