Legend™ 550 Spot User Manual 12 1/11/2010 11:36 AM
Fixture Linking
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.
Important: 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 digital DMX signal.
Maximum recommended serial data link distance: 500 m (1640 ft)
Maximum recommended number of fixtures on a serial data link: 32
Data Cabling
To link fixtures together you must obtain data cables. You can purchase CHAUVET certified DMX
cables directly from a dealer/distributor or construct your own cable. If you choose to create your own
cable please use data-grade cables that can carry a high quality signal and are less prone to
electromagnetic interference.
DMX Data Cable
Use a Belden© 9841 or equivalent 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