Page 220 - Sensors and Control Systems in Manufacturing

Fiber Optics in Sensors and Contr ol Systems
3.18.2 Daisy Chain Networks 181
The daisy chain configuration (Fig. 3.62) is an economical choice for
long straight-line installations (e.g., conveyer or mine shaft applica-
tions). The signal generated at the programmable controller is con-
verted to light and transmitted outward. At each transmitted section,
the electrical signal is reconstructed and a light signal is regenerated
and sent down the chain.

3.18.3 Active Star Networks
The electrooptical programmable controller links may be joined to an
electrooptic module with four-port and eight-port active star cou-
plers for a hub-and-spoke type system. Figure 3.63 shows two active
star couplers joined via fiber, a configuration that might be appropri-
ate where clusters of input/output racks reside in several locations

FIGURE 3.62
Daisy chain
network.