Optical link modules (OLM) for Profibus networks, OLM P22 and OLM G22, each have two optical Profibus interfaces using bayonet fiber optic connector (BFOC) technology and two electrical interfaces of the sub-D type. This arrangement enables two separate electronic Profibus segments to be integrated into one optical network structure, such as a redundant ring. Whereas the OLM P22 version supports plastic fiber-optic cable (FOC), the OLM G22 is designed for glass fiber-optic cable. Both have a signal contact as a measurement terminal with which the optical signal quality can be monitored. They can be used to construct line, star, and redundant ring structures. The transmission rate of a fiber-optic link of up to three kilometers in length is up to 12 Megabaud/second and does not depend on the distance.
Siemens Industry Automation Division
Filed Under: Networks • connectivity • fieldbuses