Instruction manual
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Power Supply: The American DJ® Comscan LED contains an elec-
tronic ballast, which will auto sense the voltage when it is plugged into 
the power source. With the electronic ballast you do not need to worry 
about wall voltage, this unit can be plugged in anywhere. Also be sure 
to only use the included I.E.C. power cable supplied with the unit.
DMX-512: DMX is short for Digital Multiplex. This is a universal pro-
tocol used by most lighting and controller manufactures as a form of 
communication  between  intelligent  fixtures  and  controllers.  A  DMX 
controller sends DMX data instructions from the controller to the fix-
ture. DMX data is sent as serial data that travels from fixture to fixture 
via the DATA “IN” and DATA “OUT” XLR terminals located on all DMX 
fixtures (most controllers only have a DATA “OUT” terminal). 
DMX  Linking:  DMX  is  a  language  allowing  all  makes  and  models 
of  different  manufactures  to  be  linked  together  and  operate  from  a 
single  controller,  as  long  as  all  xtures  and  the  controller  are  DMX 
compliant.  To  ensure  proper  DMX  data  transmission,  when  using 
several DMX fixtures try to use the shortest cable path possible. The 
order in which fixtures are connected in a DMX line does not influence 
the DMX addressing. For example; a fixture assigned a DMX address 
of 1 may be placed anywhere in a DMX line, at the beginning, at the 
end, or anywhere in the middle. Therefore, the first fixture controlled 
by the controller could be the last fixture in the chain. When a fixture 
is  assigned  a  DMX  address of  1,  the  DMX  controller knows  to  send 
DATA assigned to address 1 to that unit, no matter where it is located 
in the DMX chain.
Data Cable (DMX Cable) Requirements (For DMX and Master/Slave 
Operation): The Comscan LED  can be controlled via DMX-512 pro-
tocol.  The  Comscan  LED  is  a  ve  channel  DMX 
unit. The DMX  address is set electronically using 
the controls on the rear panel of the unit. Your unit 
and your DMX controller require a approved DMX-
512 110 Ohm Data cable for data input and  data 
output (Figure 1). We recommend Accu-Cable DMX 
cables. If you are making your own cables, be sure 
to use standard 110-120 Ohm shielded cable (This 
cable may be purchased at almost all professional 
sound and lighting stores). Your cables should be made with a male 
 Comscan LED                                               Set Up
Figure 1
and female XLR connector on either end of the cable. Also remember 
that DMX cable must be daisy chained and cannot be split.
 Comscan LED                               Set Up
Notice: Be sure to follow gures two and three when making your own 
cables. Do not use the ground lug on the XLR connector. Do not con-
nect the cable’s shield conductor to the ground lug or allow the shield 
conductor to come in contact with the XLR’s outer casing. Grounding 
the shield could cause a short circuit and erratic behavior.
Figure 3
1 Ground
1 Ground
XLR Male Socket
XLR Pin Conguration
3 Hot
2 Cold
2 Cold
3 Hot
XLR Female Socket
Pin 3 = Data True (positive)
Pin 2 = Data Compliment (negative)
Pin 1 = Ground
Special  Note:  Line  Termination.
  When  longer  runs  of  cable  are 
used, you may need to use a terminator on the last unit to avoid erratic 
behavior. A terminator is a 110-120 ohm 1/4 watt resistor which is con-
nected between pins 2 and 3 of a male XLR connector (DATA + and 
DATA -). This unit is inserted in the female XLR connector of the last 
unit in your daisy chain to terminate the line. Using a cable terminator 
(ADJ  part  number  Z-DMX/T)  will  decrease  the  possibilities  of  erratic 
behavior. 
Figure 2
DMX512 IN
3-PIN XLR
1
2
3
1
2
3
DMX +
DMX -
COMMON
DMX512 OUT
3-PIN XLR
Figure 4
1
2
3
Termination reduces signal errors and
avoids signal transmission problems
and interference. It is always advisable
to connect a DMX terminal, (Resistance
120 Ohm 1/4 W) between PIN 2 (DMX-)
and PIN 3 (DMX +) of the last fixture.










