Interlock Control System in the University Clinical Centre St. Pölten (Austria)

Germ-free medication from the hospital’s pharmacy

The University Clinical Centre St. Pölten in Lower Austria is completed in several steps. Until 2020 it shall become a state-of-the-art clinical centre model.

The distribution centre was built in 2013 and it also supplies other nearby hospitals. The distribution centre includes -among others- the clinical centre’s own pharmacy, which ensures the smooth supply of drugs, special food and cytostatic solutions, which they partially produce themselves.

The highest cleanliness and hygiene requirements apply for the production of drugs, especially for cytostatic solutions. Certain rooms may only be accessed via interlocks. Also, when leaving such rooms, sometimes interlocks are needed as a place to remove working clothes, for disinfection etc.

In the distribution centre there are 7 interlock systems with a total of 24 doors. The control of the door relations functions without any PLC control system, and are exclusively executed by the DIP switches in the control terminal on each door, which are very easy to program.

Some of the doors in the interlock systems are designated emergency exit doors. On these doors, DICTATOR emergency exit terminals tested according to EltVTR were installed, which, in addition to the functions of the interlock control system, also ensure a safe emergency escape.

The time control unit of the DICTATOR interlock control system asures that, in the changing rooms and in the disinfection interlocks, the exit doors only open after an adjustable time.

Also the card readers of the access control system of the hospital were integrated in the DICTATOR interlock control system.

This application showed once more that the system is extremely flexible, very easy to program and, thanks to the pluggable connection cables, also easy to install.

Programming example:
The picture next to last shows an interlock system with 5 doors.

The relations between the doors are determined by the position of the DIP switches in the respective control terminals.

When the door is open, doors 111 and 130 may not be opened, and doors 131 and 120 are not relevant. When door 111 is open, doors 100 and 130 may not be opened. The signs “+”, “-” and “0” shown in the matrix also mark the positions of the DIP switches in the control terminals. Thus the switches simply have to be put in the position shown in the matrix below.