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154.091UK User Manual
Caution: At the last fixture, the DMX-cable has to be terminated with a terminator. Solder
a 120Ω
resistor between Signal (-) and Signal (+) into a 3-pin XLR-plug and plug it in the DMX-output of
the last fixture.
APPENDIX
4.1 DMX Primer
There are 512 channels in a DMX-512 connection. Channels may be assigned in any manner. A fixture capable
of receiving DMX 512 will require one or a number of sequential channels. The user must assign a starting
address on the fixture that indicates the first channel reserved in the controller. There are many different
types of DMX controllable fixtures and they all may vary in the total number of channels required. Choosing a
start address should be planned in advance. Channels should never overlap. If they do, this will result in
erratic operation of the fixtures whose starting address is set incorrectly. You can however, control multiple
fixtures of the same type using the same starting address as long as the intended result is that of unison
movement or operation. In other words, the fixtures will be slaved together and all respond exactly the same.
DMX fixtures are designed to receive data through a serial Daisy Chain. A Daisy Chain connection is where the
DATA OUT of one fixture connects to the DATA IN of the next fixture. The order in which the fixtures are
connected is not important and has no effect on how a controller communicates to each fixture. Use an order
that provides for the easiest and most direct cabling. Connect fixtures using shielded two conductor twisted
pair cable with three pin XLR male to female connectors. The shield connection is pin 1, while pin 2 is Data
Negative (S-) and pin 3 is Data positive (S+).
4.2 Fixture Linking
In the Controller mode, at the last fixture in the chain, the DMX output has to be connected with a DMX
terminator. This prevents electrical noise from corrupting the DMX control signals. The DMX terminator is
simply an XLR connector with a 120W (ohm) resistor connected across pins 2
and 3, which is then plugged into the output socket on the last projector in the chain.The connections are
illustrated below.
