Pathway DMX Pathfinder CR Manual - Manual (Page 16)

DMX Distribution System Page 16
Operation
unpatched in the DMX-Q patch file, and the Input Module's channel must not
have any other connected equipment. Better still, try to use an input channel
permanently designated as "spare".
It may be necessary for the system to output a DMX signal to receiving
equipment located near the DMXPathfinder rack. In this instance, a patch
cord of sufficient length can be plugged directly into the front panel auxiliary
connector (if provided) of the opto-repeater circuit to be used, and the
corresponding station line patched in DMX-Q as though the equipment was
being connected at the remote station. Proper termination is once again an
issue here, since there are now two cable runs connected to the opto-
repeater circuit. In this case it is necessary to terminate both lines; the patch
cord at its last receiving device and the installed cable run at its remote
station or receiver, even if no equipment is connected on that end. The
Output Module's opto-repeater circuit is capable of driving two terminating
resistors.
The
DMXPathfinder offers many more signal patching possibilities, not only
for RS422A/485 based signals, but virtually any low voltage, low power
application. As a rule of thumb, no more than 24 volts or 1 amp should be
carried over the network. As mentioned above, care must be taken to
ensure that no incompatible voltages are accidentally connected to the
DMXPathfinder electronics. Always make certain before plugging patch
cords into the front panel auxiliary connectors that the associated opto-
repeater circuit's isolation relay is open. This is easy to determine, as the
SEL indicator for that circuit will be off when the relay is open, and on when it
is closed (selected). Another good practice is to remove all patch cords
when the current production ends, so that any new patch files activated will
not accidentally close isolation relays on station lines that are connected to
incompatible equipment.
Figure 1-4 is a front view of a typical output-only card frame showing locations of
SEL indicators and front panel auxiliary connectors as described on the previous
page. There are usually one or more such frames in each system, each containing
up to eight output modules and up to thirty-two station lines. The first card frame, or
Master/Input Frame, contains up to eight Input Modules and their combined total of
thirty-two front panel auxiliary connectors. Single-frame systems may have a
combination of Input and Output modules and a Master Control Module in the same
frame.