4
Signal cable selection
Use only shielded and twisted cables with EIA485 (RS485) standards. The cable must be low capacity and with an impedance
between 82 and 120 ohm. It is preferable not to use audio cables.
The wire size we recommend is 26 AWG or higher.
If the projector have cable clamps, the external diameter of cable must be compatible with cable clamps.
We suggest to use our selection signal cable or standard patch cable with compatible cannon XLR.
CAV99/040
: Flexible signal cable for
in-door
.
One pair of cable plus shield and inside safety wire.
Impedance 120 Ohm.
CAV99/037
: Polyurethane flexible signal cable for
out-door
.
One pair of cable plus shield drain wire and inside safety Kevlar wire. Impedance 120 Ohm.
EIA485 specifications
It is preferable:
-
Not to insert more than 32 power unit for each DMX chain.
-
Not to use more than 150m of signal cable (low quality cable) or 300m of signal cable (good quality cable).
-
Not to duplicate “T” way the signal cable, use a DMX Splitter.
Standard DMX controllers have only one signal out-put. If more than 32 power unit are used it is necessary to have a signal
SPLITTER, that will duplicate the signal in 2 or more lines.
If the signal cable is very long, it is necessary to install a signal AMPLIFIER on the DMX line (at least every 300m of good
quality cable), so that it will repeat the signal to the following projectors.
It is preferable, on the last power unit of the dmx signal chain, to insert a resistor (from 82 to 120 ohm) between positive and
negative terminal (+ and -).
