Contemporary Control Systems PC10420 Adapters - Manual (Page 8)

high impedance type. Do not terminate the end which attaches to the hub
port since a -CXS port effectively terminates the end of a bus segment.
Simply remove the BNC Tee connector and terminator from the segment end
and attach the cable directly to the hub port. The opposite segment end still
requires termination if no hub connection is being made.
Figure 3—Bus segments can be extended
through active hubs.
-FOG Fiber Optic (-ST, -SMA)
The fiber optic option is designated -FOG; however, a further designation is
required in order to specify the type of
connector. The -FOG-ST uses the ST
style connector while the -FOG-SMA
uses the SMA style connector. Cable
sizes of 50, 62.5 or 100 micron duplex
cable can be used with either
connector.
Fiber optic connections require a
duplex cable arrangement. Only star
and distributed star topologies are
supported. Two unidirectional cable
paths provide the duplex link. There
are two devices on each NIM. One
device, colored light gray, is the
transmitter and the other, dark gray, is the receiver. Remember that “light
goes out of the light (gray).” To establish a working link between a NIM and
another NIM or a hub to a NIM, the transmitter of point A must be
connected to a receiver at
point B. Correspondingly,
the receiver at point A must
be connected to a transmitter
at point B. This establishes
the duplex link.
Optical Power Budget
The optical power budget is
the ratio of the light source
TD874100-0IH
8
Figure 4—Fiber Optic
Option (-FOG)
Table 3—The power budget varies with
the fiber core size.