Control Data Link - Martin RUSH MH 7 Hybrid User Manual

Control data link

A DMX 512 data link is required in order to control the fixture via DMX. The
fixture has 3-pin and 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 a DMX universe and/or split the daisy-chained link into branches.
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 an amplifier is recommended for longer runs. The pin-out on all
connectors is pin 1 = shield, pin 2 = cold (-), and pin 3 = hot (+). Pins 4 and 5
in the 5-pin XLR connectors are not used in the fixture but are available 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 Watt 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:
1. Connect the DMX data output from the controller to the closest fixture's
male XLR DMX input connector.
2. Connect the first fixture's DMX output to the DMX input of the next fixture
and continue connecting fixtures output to input.
3. Terminate the last fixture on the link with a DMX termination plug.
16 RUSH™ MH 7 Hybrid User Manual