DTS DOCTUS.D 1, Руководство пользователя, Страница: 16 / 23

User Manual
Ver. 1.02 14 di 20
DOCTUS.D
5.5 Wiring
To operate, DOCTUS.D units require a DC power supply of appropriate value and a DMX/RDM connection to a
control unit for their management and configuration.
5.5.1 Characteristics of power supplies
Not all power supplies are suitable for driving the DOCTUS.D. To select the correct power supply consider that:
•
The product is class III and therefore the PSU must have a SELV type output and ensure double
insulation between input and output.
•
The output of the power supply must be adequate for the number and type of products that you want
to connect.
•
The output voltage of the power supply must be such to ensure the correct power supply to the most
distant product at the maximum load conditions. The output voltage shall, in any case, be lower than
what is foreseen for SELV power supplies, also complying with installation requirements.
5.5.2 DMX RDM network
DMX512 uses the RS-485 standard as physical layer. To connect a DMX512 controller to compatible
equipment use a bipolar cable with 120 ohm impedance and low capacitance, the data is transmitted in
differential form. There are special cables for this type of transmission with different designs suitable for
different installations.
The wiring of a RDM/DMX network must be carried out with the different devices placed in cascade avoiding
star, Y or ring connections; for this purpose there are special devices such as "splitters".
In the drafting of the cable avoid its parallel positioning to cables that supply power devices; never use the
same pipe for these two types of connection.
In the absence of repeaters, and under ideal conditions, the maximum length of a DMX or RDM network is
1200 m at a maximum speed of 100 k bps.
Without splitters or/and repeaters the maximum number of devices that can be connected is 31 plus the
console but in some particular conditions can be more.
RS-485 suggests its nodes to be networked in a daisy-chain, or bus topology. In this topology, the participating
devices, connect to a main cable trunk via short network stubs.
Daisy-chain
(Best)
Collegamento a BUS
(Works)
Star network
(AVOID)
Ring network
(AVOID)
Backbone with stars or clusters
( AVOID )