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Martin ELP CL Profile user guide
Data network requirements
A DMX 512 data link is required in order to control the fixture via DMX. The fixture has 5-pin XLR
connectors for DMX data input and output.
Up to 32 devices can be linked together on a single daisy chain. The total number of fixtures in one
512-channel DMX universe is limited by the number of DMX channels required by the fixtures.
Note that if independent control of a fixture is required, it must have its own DMX channels.
Fixtures that are required to behave identically can share the same DMX address and channels.
To add more fixtures or groups of fixtures when the above limits are reached, add another DMX
universe or split the daisy-chained link into branches using a powered DMX splitter.
Tips for reliable data transmission
Use shielded twisted-pair cable designed for RS-485 devices: standard microphone cable cannot
transmit control data reliably over long runs. 24 AWG cable is suitable for runs up to 300 meters
(1000 ft.). Heavier gauge cable and/or a DMX buffer is recommended for longer runs. The pin-out
on all connectors is:
•
pin 1 = shield
•
pin 2 = cold (-)
•
pin 3 = hot (+).
Pins 4 and 5 in the XLR connectors are not used in the fixture but are passed through for possible
additional data signals as required by the DMX512-A standard. Standard pin-out is pin 4 = data 2
cold (-) and pin 5 = data 2 hot (+).
To split the link into branches, use an opto-isolated splitter such as the Martin™ DMX 5.3 Splitter.
Terminate the link by installing a termination plug in the output socket of the last fixture. The
termination plug, which is a male XLR plug with a 120 Ohm, 0.25 W resistor soldered between
pins 2 and 3, “soaks up” the control signal so it does not reflect and cause interference. If a splitter
is used, terminate each branch of the link.
Connecting the data link
To connect the fixture to data:
•
Connect the DMX data output from the controller to the closest fixture’s male XLR DMX input
connector.
•
Connect the first fixture’s DMX output to the DMX input of the next fixture and continue
connecting fixtures output to input. Terminate the last fixture on the link with a DMX
termination plug.
