Description
The Ekinex® DMX - KNX Gateway performs a protocol conversion between a serial
RS485 DMX and a KNX TP network. The device works as DMX master. The device
integrates a KNX bus communication module and it is suitable for mounting on a 35
mm DIN rail; it requires an auxiliary power supply.
Main features
• Plastic casing
• Connection to bus line with KNX terminal block
• Installation on 35 mm rail (according to EN 60715)
• 4 modular units (1 MU = 18 mm)
• IP20 protection degree (installed device)
• Weight 145 g
Technical data
• Power supply: 8...24 Vac or 12...35 Vdc
• Absorption at 24 Vdc: 3,5 VA
Communication
KNX side
• KNX TP (Twisted Pair) communication port electrically isolated from power supply
• 1440-byte volatile support “KNX image” memory buffer
DMX side
• RS485 serial communication port, electrically isolated from power supply,
120 ohm termination resistance pluggable by a 1-way microswitch
• DMX master communication
• Baud rate 250 kbaud
• Device addressing from 0 to 512
• 1-byte register writing on max 512 DMX devices
Configuration
• Ethernet communication port (IEEE 802.3), RJ45 connector, minimum cable
category: 5E
Products included
The delivery includes the device and terminal blocks to connect to the KNX bus.
Gateway DMX - KNX
GATEWAY
+
-
KNX
1
2
8...24 Vac
+V
0V
POWER S.
12...35 Vdc
3
4
5
RS485
ETHERNET
Dev.
Line
Area
KNX
Device state
DMX
EK-BK1-TP
DMX / KNX TP Converter
Failure
RT-
Com
RT+
RT+
RT-
Com
RS-485
DMX
+
8-24 Vac o
12-35 Vdc
DMX, acronym for Digital Multiplex, is a communication protocol for lighting control,
developed as digital transmission method for data between controllers and controlled
devices, including dimmers and related equipment. This standard is oriented to
guarantee interoperability both for communication and mechanics among controllers
from different manufacturers.
Origin and evolution
USITT (United States Institute of Theatre Technology) develops and promotes a wide
range of technologic standards for theatric and show-business industry. Among
those, in 1986 USITT has developed DMX512 as standard protocol for lighting
control. In 1988 USITT has transferred the maintenance of the protocol to ESTA
(Entertainment Services and Technology Association), a non-lucrative category
association representing the entertainment industry of technology. In 2004,
ANSI (American National Standards Institute) approved the DMX512 standard and
subsequently other related rules. The standard is constantly reviewed and updated
along with the progress of technology: the devices which are compliant to the
2008 release are marked with the DMX512-A notation in order to distinguish them
from those developed according to the previous releases. Although developed and
acknowledged in the US only, DMX512 is spread worldwide.
Standard characteristics
DMX512 is based on a serial asynchronous 8-bit protocol composed by an
uncompressed byte stream which is produced by a standard universal asynchronous
receiver-transmitter (UART); the ‘512’ suffix refers to the maximum number of
addresses configurable in a DMX field, called “DMX universe”. If two DMX devices
connected to a universe have the same address, they are controlled in parallel. The
transmission medium is normally (although not exclusively) a twin couple conductor,
with each couple acting as data connection. If necessary, repeaters can be used in
order to overcome the length limit of a DMX network. The connection of the devices is
carried out with 5-pole XLR connectors or by physically connect the terminal blocks.
The data on the primary connection is sent in packets up to 513 slots; the first slot is
composed by a starting code which defines the information on the subsequent slots
of the packet. Interoperability among standard compliant devices is mostly due to the
use of the NULL START code by the transmitting devices.
Fields of application
DMX512 is not a general-purpose lighting standard: both device designers
and standard users use DMX512 for a limited range of applications, mostly for
entertainment industry when a central direction console needs to control the
scenic lighting composed by a big number of lights and effects, and for the scenic
illumination of historic buildings. Other standards are more suitable for other uses:
for example, DMX512 cannot support a network designed to transmit sound and
scenic actuators on the same transmission medium as lights.
Rules reference
ANSI E1.11 - Entertainment Technology USITT DMX512-A - Asynchronous Serial
Digital Data Transmission Standard for Controlling Lighting Equipment and
Accessories
ANSI E1.20 - Entertainment Technology RDM - Remote Device Management over
USITT DMX512
ANSI E1.17 - Entertainment Technology ACN – Architecture for Control Networks
(Multipurpose Network Control Protocol Suite)
DMX512
DIGITAL MULTIPLEX
Versions
Code
EK-BK1-TP
Documentation
For further details, consult the technical sheet
STEKBK1TP_EN.pdf, available for download at www.ekinex.com
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SMART LIGHTING
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