1.5
DMX CABLES
Only use specific DMX data cable. The data cable must conform to the EIA485 cable
requirements by providing the following specifications:
•
Low capacitance
•
One or more twisted pairs
•
Foil and braid shielded
•
Impedance of 85-150 ohms, nominally 120 ohms
•
22AWG gauge for continuous lengths over 300 metres
If you want to make your own cables LSC recommends using Beldon 9842 (or
equivalent). Never use audio cable.
The end of the DMX line must be terminated (120
Ω
) to prevent the signal reflecting
back up the line and causing possible errors.
1.6
PUSH-FIT TERMINALS
The following cables are suitable for use with the push-fit terminals:
•
2.5mm² stranded wire
•
4.0mm² solid wire
Stripping length is 8mm.
Insert a small screwdriver into the slot adjacent to the cable hole. This releases the
spring inside the connector. Insert the cable into the round hole then remove the
screwdriver. Solid wires or wires fitted with ferrules can often be pushed directly
into the connector without the use of the screwdriver. When connecting multiple
cables to a single terminal the wires must be twisted together to ensure a good
connection to both legs. Non-insulated bootlace ferrules can also be used for
stranded cables. Ferrules are not recommended for solid cables. Insulated bootlace
ferrules can also be used allowing stranded cables to be easily inserted without the
need of a tool to actuate the spring release. The maximum ferrule outer diameter is
4mm.
1.7
RJ45 DMX CONNECTOR PIN-OUTS
RJ45 8-Pin Connector Function
Pin 1
DMX +ve
Pin 2
DMX
–
ve
Pin 3
Not Connected
Pin 4
Not Connected
Pin 5
Not Connected
Pin 6
Not Connected
Pin 7
Common
Pin 8
Common
Page 2
1.8
MDR-DIN SPECIFICATIONS
Power Requirements
9-24V DC, 5W
Power Input Connector
Quick Connect Terminals
Reverse Polarity Protected
Yes
Input and Thru Connectors
RJ45 or Quick Connect Terminals
Output Connectors
RJ45 or Quick Connect Terminals
Number of Buffered Outputs
4
DMX Protocol
ANSI DMX512A Standard E1.11:2008 (R2013)
RDM Protocol
ANSI RDM Standard E1.20:2010
RDM
Can be individually disabled on each output
All Inputs and all Outputs Isolated
Yes
Galvanic Isolation Barrier
1500V
Short Circuit Protected
Yes
DMX512 Data LED
Yes (Flashes when DMX data is present)
RDM Data LED
Yes (Flashes when RDM data is present)
Power LED
Yes (Flashes when RDM Identify is received)
Conformity
CE, RCM
Note:
All outputs are individually isolated from each other as well as the input.
Isolation is for both data and common connections and provides a galvanic
barrier to 1500V. Outputs are EMI-filtered and current-limited to protect against
short circuits.
1.9
DMX EXPLAINED
DMX512-A is the industry standard for the transmission of digital control signals
between lighting equipment. It utilises just a single pair of wires on which is
transmitted the level information for the control of up to 512 DMX slots
(addresses or channels).
The information for each slot is sent sequentially. The level of slot 1 is
transmitted, then the level of slot 2, then 3, etc., up to a maximum of 512 slots.
This stream of data containing the levels for all 512 DMX slots is repeated a
minimum (generally) of 44 times per second. This provides sufficient updates of
channel information for smooth fade transitions.
DMX allows a controller to communicate with a device. It does not allow the
device to communicate with the controller.
1.10
RDM EXPLAINED
RDM allows RDM-based controllers and devices to communicate with each other
in bidirectional mode over the DMX cable, interleaved with the DMX512-A signal.
Page 3