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You will need a serial data link to run light shows of one or more fixtures using a DMX controller or to
run synchronized shows on two or more fixtures set to a master/slave operating mode. The combined
number of channels required by all the fixtures on a serial data link determines the number of fixtures the
data link can support.
Fixture Linking
Fixtures on a serial data link must be daisy chained in one single line. To comply with
the EIA-485 standard, no more than 32 fixtures should be connected on one data link.
Connecting more than 32 fixtures on one serial data link without the use of a DMX optically-
isolated splitter may result in deterioration of the DMX signal.
Maximum recommended serial data link distance:
500 m (1640 ft)
Maximum recommended number of fixtures on a serial data link:
32
Use a cable which meets the specifications for EIA RS-485 applications. Standard microphone cables
cannot transmit DMX data reliably over long distances. The cable must have the following characteristics:
Type:
Shielded, 2-conductor, twisted pair
Maximum capacitance between conductors:
30 pF/ft
Maximum capacitance between conductor and shield: 55 pF/ft
Maximum resistance:
20 Ohms/1000 ft
Nominal impedance:
100 ~ 140 Ohms
DMX Data Cable
Cabling must have a male XLR connector on one end and a female XLR connector on the other end.
Cable Connectors
Do not allow contact between the common and the fixture’s chassis ground. Grounding
the common can cause a ground loop, and your fixture may perform erratically. Test cables
with an Ohm meter to verify correct polarity and to make sure the pins are not grounded or
shorted to the shield or each other.
