LYTEMODE® DMX MASTER STATION USER’SGUIDE ABOUT DMX512
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About DMX512
What is DMX512?
DMX512 (often shortened to simply "DMX") is a standardized digital communication signal used to
interconnect different kinds of microprocessor-based lighting control equipment. It uses a special data
communication cable to transmit information to the various pieces of lighting equipment (Dimmers,
Color Changers, Remote Controlled Spotlights, etc.). "DMX" stands for Digital MultipleX, a
technique by which information for many devices may be transmitted digitally over one cable.
The messages transmitted in a DMX512 system tell the lighting equipment what to do. For example,
messages might set a lamp dimmer to 80% intensity, tell a color changer to go to a blue color, or direct
a moving spotlight to shine on the lead singer in a band. These messages are sent by the lighting
controller.
To construct a DMX512 control system, a specialized cable must be run from the lighting controller to
every controlled device in the facility. In most cases this cable will connect in a daisy-chain fashion
from one device to the next until it reaches the last device in the system. When properly connected, all
devices in the facility will instantly respond to commands sent from the lighting controller.
What Electrical Signals are Used with DMX512?
DMX512 is based on an electronic signaling standard called EIA-485. Under this standard, signals are
sent down a pair of wires, while an additional single wire provides a common voltage reference for the
system. So, in order to create one message channel, you need three wires: the two wires in the twisted
pair, and the common reference wire. If a second message channel is required, you only need to add a
second twisted pair. The common reference wire can serve both pairs.
DMX512 requires two message channels, so it uses cable which contains two twisted pairs of wire,
and one common wire. The common wire also serves as an electrical shield for the cable. So there are
a total of five wires in a complete DMX512 cable.
Device Device Device Device
LYTEmode® DMX
Master Station Controller
DMX512 Cable
Twisted Pair
Drain (Common Reference)
Twisted Pair
APPENDIX B: EXPANSION PORT DRY CONTACT INPUTS LYTEMODE® DMX MASTER STATION USER’SGUIDE
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Appendix B: Expansion Port Dry Contact Inputs
A 16-position terminal strip located on the back of the DMX Master Station unit is used to hardwire
alarms and other remote lock devices into the system. This strip is divided into eight inputs with
common and six LED outputs with drive. The function of these inputs and outputs can be changed by
setting its mode options. Functions include:
•Cinema Cycle - A remote closure causes the unit to cycle through Scenes A, B, C and D. This
closure comes from a projector and can automatically control the lights in a movie theater. The ON
Scene is reserved for ‘clean up/emergency.’
•Alarm - A remote closure comes from the alarm system and causes all the channels to either go to
Full On or cycle between Full Off and Off. Refer to "Alarm Flash/Full" on page 33.
Once the terminal strip is wired according to the desired network configuration, the Terminal Strip
Mode must be set for proper operation. This section provides instructions for wiring the various
components and setting the proper mode.
Terminal Strip Modes
Depending on the mode, the terminal strip will read inputs and write outputs differently. To set the
mode, refer to "Expansion Port Mode" on page 30.
Table 2: Terminal Strip Signals by Mode
Pin Mode 0 Mode 1 Mode 2 Mode 3
1 LED Common LED Common Not Used Not Used
2 OFF LED OFF LED
3 D LED I LED
4 C LED H LED
5 B LED G LED
6 A LED F LED
7 ON LED E LED
8 Button Common Button Common Button Common
9 Lower (1) Lower (1) Alarm
10 Raise (1) Raise (1) Cycle
11 OFF Button OFF Button Panel Lock
12 D Button I Button Remote Lock
13 C Button H Button n/a
14 B Button G Button n/a
15 A Button F Button n/a
16 On Button E Button n/a
