Medical Isolated Power Systems

Group 2 including operation room, cardiac area, intensive care unit is most critical part for electricity sustainability and insulation.

Electrical devices in group 2 save patients life. When there are any failure of the devices in this environment without harming the people in the medical location, devices are required to work without interruption. For this reason, IT isolated power system is used in the Group 2 area.

Network installation regulations distinguishes three families of earthing arrangements, using the twoletter codes TN, TT, and IT.

The first letter indicates the connection between earth and the power-supply equipment (generator or transformer):

“T” — Direct connection of a point with earth,
“I” — No point is connected with earth (isolation), except perhaps via a high impedance

The second letter indicates the connection between earth and the electrical device being supplied:
“T” — Direct connection of a point with earth,
“N” — Direct connection to neutral at the origin of installation, which is connected to the earth.

The next letter (If it is exist) indicates the regulations of neutral and protection conductor:
“S” — Provide protection function with separate conductor from neutral or earthed line conductor,
“C” — Combining neutral and protection safety on single conductor (PEN conductor).

All live parts are separated from the ground or from a point connected to ground via a high impedance. The exposed conductive parts of the electrical installation is grounded separately or combined or connected to the system ground.

At the IT systems used in group 2 rooms in medical environments, isolation transformer is used to separate the grounding of the neutral conductor and phase conductor. The grounding plug is connected to the equipotential bus. In isolated power systems, grounding are insulated against both lines. If a low resistance short circuit touches the ground or a leakage occurs, continue to the function of the circuit breaker and do not open and medical electrical equipment is continue to their functionality.

Also because of grounding network is isolated as create a very high resistance to earth will pass current level will not harm even through touching people. In isolated power systems, insulation levels, transformer temperature and the load current is continuously monitored and a possible case of failure alarm signal is generated. The alarm signal is provided the necessary interventions by transmitted to related panels

Environments that use of isolated power systems in hospitals:

* Operation Rooms
* Surgery Preparation Room
* Intensice Care Units
* Anesthesia Room
* Cardiac Catheterization Rooms
* Angiographic Surgery Rooms
* Premature Baby Rooms