High End Systems Studio Command 1200, User Manual

Page: 23 / 108

CHAPTER 2
Setup and Configuration
Studio Command Series User Manual 13
Linking the Fixtures
The combined number of channels required by all the fixtures on a DMX 512 link determines the
number of fixtures the link can support. Each Studio Command fixture uses 14 channels on a
DMX512 link.
Studio Command-H fixtures use 13 channels plus a channel dedicated to a dimmer.
Note: If you connect more than 32 fixtures to a link, you must use a DMX
splitter. The 32 device limit complies with the EIA-485 standard.
Connecting more than 32 devices per link without a DMX splitter will
eventually deteriorate the digital signal.
Controllers, serial data distributors, data line optoisolators, and any fixtures using the RS-422
DMX standard of serial communications block software uploads, crossloads, or TalkBack™
protocol on a link. Therefore, make sure you either put all of these devices after the Studio
Command fixture on the link, or bypass these devices when you perform software uploads or
crossloads
Data Cabling and Connectors
To link one or more fixtures to a controller and/or to each other, you must obtain data cabling.
You can either purchase cabling from High End Systems (see Related Products and Accessories
on page 4) or construct your own cabling.
If you choose to construct cabling, High End Systems recommends that you use data-grade
cable. Data-grade cable is designed to carry a high-quality signal with less susceptibility to
electromagnetic interference.
DMX data cables:
Belden
®
9841 or equivalent (meets specifications for EIA RS-485 applications) with the
following characteristics:
• 2-conductor twisted pair plus a shield
• maximum capacitance between conductors - 30 pF/ft.
• maximum capacitance between conductor and shield - 55 pF/ft.
• maximum resistance of 20
Ω
/ 1000 ft.
• nominal impedance 100-140
Ω