Rdm connections – Tempest Hurricane User Manual
Page 43

Hurricane Enclosure User Manual
page 43
installations. The individual fixtures installed inside the Tempest enclosures must NOT be
terminated. It is recommended that any line termination is done using the 3-pin terminal
connector fitted to the DEC3 control circuit board.
1.
Make sure that any DMX termination provided by the fixture inside your enclosure(s) is
disabled.
2.
The LAST enclosure in the installed DMX daisy chain should have a DMX Termination
fitted to one of the pass through DMX connectors. Per the ANSI E1.11 standard, the
Terminator shall be 120 ohm +5%/-10% impedance placed between Data+ and Data-. We
recommend minimum power rating of 0.6W for the resistor.
We recommend that the installer fit a label externally to say “DMX Termination fitted
internally”.
Test:
3.
Switch mains power OFF to all enclosures.
4.
Before connecting the DMX line to your controller, measure the impedance between Pin 2
(Data-) and Pin 3(Data+) at the controller end. Reading should be around 100-130 ohms.
This test shows that you have a terminator in place, and also that you have continuity of Data- and
Data+ between installed devices. If the measured resistance is significantly less than 100 ohms,
(say 40-80 ohms) it suggests you may have multiple terminations in place. Check that any
terminator switches on light fixtures are OFF. If impedance is very low, check for wiring shorts.
RDM Connections
RDM refers to ANSI E1.20, a control protocol in the entertainment industry gaining popularity and
essentially an “extension” of DMX512. The use of RDM is optional – but it does require a DMX512
cable connection.