Data Cabling; Dmx Data Cable; Dmx Cable Connectors - Chauvet Legend 1200E Wash User Manual

Data Cabling

DMX Data Cable

DMX Cable
Connectors
Legend™ 1200E Wash User Manual
You must use DMX compliant data cables to link two or more DMX compatible
fixtures together. You may purchase CHAUVET certified DMX cables directly from a
dealer/distributor or construct your own cable.
USITT recommends limiting the total length of the DMX cable (from the first
fixture/controller to the last fixture) to 300 ~ 455 m (985 ~ 1,500 ft).
If you choose to create your own cable, make sure to use data-grade cables that
can carry a high frequency signal and are less prone to electromagnetic
interference. Use a Belden© 9841 or equivalent cable, which meets the
specifications for EIA RS-485 applications.
Do not use standard microphone cables for DMX applications because they
cannot transmit DMX data reliably over long distances.
The data cable must have the following characteristics:
Type:
Maximum capacitance between conductors:
Maximum capacitance between conductor and shield:
Maximum resistance:
Nominal impedance:
Each DMX cable must have a male, 3 or 5-pin XLR
connector on one end and a female, 3 or 5-pin XLR
connector on the other end.
DMX Connector
To DMX Input
(Female)
Common
1
DMX +
3
2
DMX -
To avoid signal transmission problems and interference, it is always advisable to
connect a DMX signal terminator, as seen below.
1
3
2
Test all DMX cables with an ohmmeter to verify their correct polarity and to
make sure that there are no short-circuits between any of the pins, or between
any pin and ground. If the Common wire touched the chassis ground, a
ground loop could form, which may cause the fixture to perform erratically.
9
shielded, 2-conductor twisted pair
Configu
To DMX Output
ration
(Male)
1
3
2
120 ohm, ¼ W
resistor between
pin 2 (DMX -) and
pin 3 (DMX +) on
the output of the
last fixture.
Setup
30 pF/ft
55 pF/ft
20 ohms/1000 ft
100 ~ 140 ohms
120 ohm, ¼ W
resistor between
pin 2 (DMX -) and
pin 3 (DMX +) on
the output of the
last fixture.
8/13/2009 10:55 AM