Contemporary Control Systems USB222 Adapters - Manual (Page 4)

TD040900-0II
4
INSTALLATION
SOFTWARE
Driver installation instructions are provided in the readme file located on the
disk that accompanies the product.
INDICATOR LIGHTS
ARCNET: This LED will flash green in response to any ARCNET
activity.
USB: This LED glows green so long as a valid active USB
connection exists to an attached computer.
FIELD CONNECTIONS
The USB22 is available in four models that vary by transceiver type for
connecting to an ARCNET LAN via a particular kind of cable. Each
model’s transceiver is identified by the suffix (-4000, -485, -CXB or -
TB5) separated from the main number by a hyphen.
-CXB Coaxial Bus
Generally two types of coaxial cables are used with ARCNET: RG-62/u
and RG-59/u. RG-62/u is recommended because it matches the 93-ohm -
CXB impedance and can thus achieve the maximum 1000-foot segment
distance. Although RG-59/u does not match the -CXB impedance (it is
75-ohm cable), it will still work but the segment length may be limited.
Never attach coax cable directly to the USB22-CXB; always use the
provided BNC “T” connector. The “T” connector allows the coaxial bus
to continue as shown with device A in Figure 43. Apply the provided
93-ohm BNC terminator to the “T” if the USB22 terminates the coax in an
end-of-line situation as shown with device B in Figure 43.
Figure 4 — Possible Connections for the USB22-CXB