Optical sensor EIB/KNX gateway

Abstract

Nowadays, there are some special building like for example power or chemical plants, where convetional electronic sensors cannot be used as they are exposed to explosive enviroments or due to the presence of either electromagnetic interferences, or chemical or mechanical disturbances. Because of that, those sensors cannot operate and monitor correctly the target parameters. In these cases, the use of optical fiber sensors is a valid alternative due to their passive nature, inmunity to electromagnetic interference, small size and light weight, avoidance of ground loops, capability of responding to a wide variety of parameters, durability, resistance to harsh environment, remote operation or capability of multiplexing among others advantages. On the other hand, the control and monitoring of that kind of buildings are necessary and very important, so Intelligent Building systems as EIB or Konnex should offer a solution. This work describes the development of a new gateway consisting of an EIB module intended to connect optical fiber sensors directly to bus. That is, a new input module where the optical signal from this kind of sensors is analyzed and translated to the EIB communication protocol. The first prototypes include four optical inputs (FC/PC and SMA optical connectors) and is equipped with different photodiodes to receive optical power at 1310nm and 1550nm (standard telecommunication wavelength). Furthermore, the module also includes two optical sources at 1310nm and 1550nm to illuminate the optical fiber sensors and an optical coupler if the optical copler if the optical sensors use a reflection scheme. In order to adapt the optical signal to the EIB bus signal the module also includes a BIM. In short, a new opto-electronic input module for EIB system has been designed for its application in special buildings where traditional sensors cannot be used due to the hostile enviroment.