Logic input and output peripherals

An evacuation center is a system of controls and monitoring. There is almost always a processor system built to perform all functions. Consequently, there is also embedded software built into the system. The logic usually consists of a keypad with display or laptop connection.

The requirement is that statuses and errors can be read easily on the system.

The system is usually controlled from a control panel. This is called the entrance periphery. In most  cases, this is done on the basis of potential-free relay contacts. Super simple and absolutely reliable. When using a fire alarm and voice alarm evacuation system of the same brand it is common that data gets mutually exchanged via communication.

This is cost-saving for the customer. It is absolutely not a better system, ergo if data corruption occurs under external influences (EMC) on the communication, there is no data communication. A old-fashioned potential free contact has no problems with this.

Within the world of fire safety there is no standard developed for a variety of brands of equipment to communicate via a digital protocol with each other, and this can truly be considered as a shortcoming. In the short term we will not expect any change here.

‘’The output periphery usually consists of a number of modules that communicate via a zone-oriented control system with the speakers’’

The application of embedded software had led to formulate, regarding this software, certain directives in the product standard EN54-16. Within the software, development choices can be made regarding controls that are not suitable for the application. There will be looked at this extendedly during the testing and there will be also separate assessments conducted on this software.

The manufacturer also serves a large number of principles to explain before the software is approved. This may sound tough, but we are talking about a security installation.

‘’An error in the embedded software is disastrous and the probability of failure should be as low as possible’’