How to use a medical network isolator
and why is the use of an isolating transformer is insufficient
With increasing digitalization, active medical devices are more and more often combined with network components and PCs. This creates a growing risk in almost all medical facilities, hospitals and clinics – the risk of a high leakage current via the Ethernet data network is possible, with potential impact to the patient. Therefore the standards for electrical safety in medical technology (IEC 60601-1) require the electrical isolation of the signal line, whenever an electrical device within the patient environment is connected to a server. Our MI 1005 network isolator resolves this problem by isolating currents and voltages in the data network line up to a maximum of 5000V. Patients are safe and cannot get violated via currents and voltages.
The following example visualizes the problem and shows why the use of an isolation transformer is not sufficient.
No electrical protection despite of the use of an isolating transformer
In Fig. 1, a gastroscopy is performed to a patient. The patient is directly connected to the cart solution via the gastroscope. The patient data is transferred via the network cable to a PC, which is connected to the hospital network via the network interface. An isolating transformer was used to ensure the electrical safety. By connecting the medical device or system (PC, measuring station,...) to a network (LAN) the electrical safety is disabled. The reason for this is, that the LAN connection via the network cable is not electrically secured (isolated). The network error is passed on into the gastroscopy cart. A malfunction can also occur to the connected devices and they may even be destroyed. In the worst case, the technical failure will impact the patient; the result can be an electrical shock.
In Fig. 2, the network isolator MED MI 1005 is inserted between the LAN output socket and the medical device or system (PC, measuring station,...), therefore the complete system is electrically isolated from the LAN. The malfunction in the network cannot impact the patient.