XM974-V1.0-NR
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6. DMX-512 connection with DMX terminator
For installations where the DMX cable has to run a long distance or is in an electrically noisy
environment, such as in a discotheque, it is recommended to use a DMX terminator. This helps in
preventing corruption of the digital control signal by electrical noise. The DMX terminator is
simply an XLR plug with a 120
Ω
resistor connected between pins 2 and 3,which is then plugged
into the output XLR socket of the last fixture in the chain. Please see illustrations below.
7. Projector DMX start address selection
All fixtures should be given a DMX starting address when using a DMX signal, so that the
correct fixture responds to the correct control signals. This digital starting address is the channel
number from which the fixture starts to “listen” to the digital control information sent out from
the DMX controller. The allocation of this starting address is achieved by setting the correct
number on the display located on the base of the device.
You can set the same starting address for all fixtures or a group of fixtures, or make different
address for each fixture individually.
If you set the same address, all the units will start to “listen” to the same control signal from the
same channel number. In other words, changing the settings of one channel will affect all the
fixtures simultaneously.
If you set a different address, each unit will start to “listen” to the channel number you have set,
based on the quantity of control channels of the unit. That means changing the settings of one
channel will affect only the selected fixture.
Address 1 Address 13 Address 25