Contemporary Control Systems QuickLink Active Hubs - Manual

QUICKLINK
A Line of External Fixed-Port Active Hubs for ARCNET® Local Area Networks
INSTALLATION GUIDE
INTRODUCTION
The QuickLink (QL) Series of external fixed port hubs provides a low cost
method of expanding ARCNET local area networks. These eight-port hubs
provide the ultimate in reliability and flexibility for cabling ARCNET
networks. A hub allows for the addition of a segment and support for
distributed star topologies. The QL utilizes the same robust hub timing
electronics found in
the Contemporary Controls (CC) MODHUB series for
modular active hubs. This includes precision delay line timing, digitally
controlled timers for dependable operation and reduced bit jitter. A
lso, a
watchdog timer is included to prevent hub lockup — eliminating the need
to recycle hub power in the event of extraordinary electrical disturbance.
The QL operates from low -voltage AC, requiring a power voltage source in
the range of 8 to 24 volts.
Active hubs increase the robustness of ARCNET networks. They maximize
the distance that can be achieved on each cable segment
⎯
up to 2000 feet
(610 m) feet on coaxial segments. They prevent interference to the network
by squelching reflections caused by open or shorted cable segments attached
to the hub. Unused hub ports need not be terminated. Active hubs allow for
a distributed star topology, thereby minimizing the cabling required in a
facility. Two or more QL hubs may be cascaded.