Isolationövervakningsenheter

Isolationövervakningsenheter, often translated as isolation monitoring devices or insulation monitoring units, are electrical safety devices used to detect and alert on the loss of insulation resistance in a system. Their primary function is to continuously measure the insulation level between the live conductors of an electrical system and ground. A significant drop in insulation resistance can indicate a potential fault, such as damaged wiring, moisture ingress, or conductor degradation.

These devices are particularly crucial in systems where continuity of supply and a high level of safety are paramount, such as medical facilities, industrial processes, and IT data centers. In a medical context, they are essential for protecting patients from dangerous electrical currents in case of an equipment fault. By providing an early warning, isolationövervakningsenheter allow for maintenance to be scheduled before a complete insulation failure occurs, which could lead to equipment damage, system downtime, or even electrical hazards.

The devices operate by injecting a small, non-destructive test voltage into the system and measuring the resulting current flow to ground. If this current exceeds a pre-set threshold, indicating low insulation resistance, the device will trigger an alarm. This alarm can be visual, audible, or communicated remotely to a control system. Different types of isolation monitoring devices exist, including AC and DC variants, and those designed for specific voltage levels and system configurations. Their presence is a key component of a comprehensive electrical safety strategy.