DMX-150SQ User Manual
10
2005-05-05/09:34
A
PPENDIX
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+). CHAUVET
carries 3-pin XLR DMX compliant cables, DMX-10 (33
’
), DMX
-4.5 (15
’
) and DMX
-1.5 (5
’
)
F I XT URE LI NKI NG
Note!
If you use a controller with a 5 pin DMX output connector, you will need to use a 5
pin to 3 pin adapter. CHAUVET Model No: DMX5M.
The chart below details a proper cable conversion:
3
P
IN TO
5
P
IN
C
ONVERSION
C
HART
C
ONDUCTOR
3 Pin Female (output)
5 Pin Male (Input)
G
ROUND
/S
HIELD
Pin 1
Pin 1
D
ATA
(
-
)
SIGNAL
Pin 2
Pin 2
D
ATA
(
+
)
SIGNAL
Pin 3
Pin 3
D
O NOT USE
Do not use
D
O NOT USE
Do not use
COMMON
DMX +
DMX -
INPUT
OUTPUT
1
3
2
1
3
2
1
3
2
Resistance 120
ohm 1/4w between
pin 2 (DMX -) and
pin 3 (DMX +) of
the last fixture.
Termination reduces signal errors and to
avoid signal transmission problems and
interference, it is always advisable to connect
a DMX signal terminator.
Figure 2 - DMX connector configuration
