Siemens SIMATIC NET PROFIBUS manual Transmission Technique for Wireless Infrared Technology

PROFIBUS NETWORKS

1.2.6Transmission Technique for Wireless Infrared Technology

The wireless PROFIBUS network uses infrared light for signal transmission. The only transmission medium is a free line-of-sight connection between two nodes. The maximum distance covered is approximately 15 m. Wireless networks are implemented using infrared link modules (ILM). The nodes to be networked are attached to the electrical port of the ILM.

Advantages:

SHigh mobility of attached plant components (for example trolleys)

SCoupling and decoupling from the fixed network with no wear and tear (for example substitute for a slip ring)

SCoupling without cable installation (temporary setup, inaccessible areas)

SNot protocol dependent

SElectrical isolation between nodes and hardwired network

Restrictions

STransmission rate <= 1.5 Mbps

SFree line-of-sight path required between nodes

SMaximum distance covered <= 15 m

SOnly for single master networks

Characteristics of the Wireless Infrared Transmission Technique

The wireless infrared transmission technique has the following characteristics:

Network topology:	Point-to-point
	Point-to-multipoint
Medium:	Free space with line-of-sight path
Maximum link length:	15 m
Transmission rate ILM:	9.6 Kbps, 19.2 Kbps, 45.45 Kbps, 93.75 Kbps, 187.5 Kbps,
	500 Kbps, 1.5 Mbps
Number of nodes:	Maximum 127 per network

1-14	PROFIBUS Networks SIMATIC NET
	6GK1970-5CA20-0AA1 Release 2 05/2000