Harman Martin Exterior Projection 1000, User Manual

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18 Exterior Projection 1000 User Manual
Control data link
A DMX512 data link is required in order to control the fixture via DMX (and manage fixtures via
RDM, if used). Your Martin supplier will be happy to help if you need advice or assistance in
planning the link.
Follow these guidelines when creating a DMX data link:
• Use RS-485 data cable designed for exterior use. RS-485 cable has low capacitance and a
characteristic impedance of 85 to 150 Ohms. It is electrically shielded and has at least one
twisted pair of conductors. The minimum recommended wire size is 0.25 mm2 (24 AWG) for
runs up to 300 meters (1000 ft.) and 0.32 mm2 (22 AWG) for runs up 500 meters (1640 ft.). A
cable run of more than 500 meters requires the use of a splitter-amplifier to boost the DMX
signal.
•
If independent control of a fixture is required, that fixture must have its own DMX channels. Any
fixtures that will always be required to behave identically can have the same DMX address,
which means that they will use the same DMX channels.
•
512 DMX channels are available in a single DMX universe. Each time the number of DMX
channels required by the fixtures on a data link reaches 512 and you want to add more fixtures,
create a new DMX universe on a new data link and connect the additional fixtures to the new
link.
•
You can connect up to 32 fixtures in a single daisy chain on a DMX data link. Connecting in a
daisy chain means that you must connect the DMX data OUT from one fixture to the DMX data
IN of the next fixture, creating a single line of fixtures. Do not split the link into branches by
creating a
Y shape in the cable or at connectors.
•
However, you can split a DMX data link into two or more branches if you use an optically
isolated DMX splitter-amplifier. To preserve RDM functionality, use an RDM-compatible splitter
such as the Martin RDM 5.5 Splitter. Each branch can contain up to 32 fixtures.
• If you reach the limit of 32 fixtures on a DMX data link, you can connect up to 32 additional
fixtures if you add a splitter-amplifier such as the Martin RDM 5.5 Splitter to the link in order to
boost the data signal. Adding a splitter-amplifier also lets you extend a data link beyond 500
meters (1640 ft.).
• The data link (and each branch of the link if you have created branches with a splitter-amplifier)
must be terminated at the end by placing a 120 ohm resistor (available from Martin, P/N
04150308) across the data output hot (+) and data output cold (-) conductors of the last fixture
on the link.
• Do not create long parallel runs of AC power and data cables, as these may cause interference
on the data link. Even if not required by law, use separate conduits for power and data cables.
•
The Exterior Projection 1000’s combined data input/output cable does not support the optional
second data wire pair that is provided for in the DMX512-A standard. Do not place devices that
use the second data pair on the same DMX data link as Exterior Projection 1000 fixtures.
Connecting the data link
Important! Protect all connections and all breaks in cable jackets from moisture (see ‘Protecting
connections from moisture’ on page 16).
Important! Connect the data output from one fixture to the data input of one fixture only. If you
connect one data output to more than one data input, you will split the DMX data link into branches
which will probably cause data signal integrity problems.
The Exterior Projection 1000 is supplied with a hard-wired 1.8 m (5.9 ft.) shielded cable with 2
pairs of wires for connection to a DMX data link.