Videotec DCIR, Руководство по эксплуатации

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Pag. 6 DCIR_4402
Telemetry via coaxial cable
The DCIR can be used for telemetry transmission via coaxial cable using matrixes of the type SM42A, SM82A,
SM84A, SM164A. Set up the MACRO type video line in both the DCIR and the matrix. It is important to use a
sufficiently fast baud rate (we recommend a baud rate setting of 38400). Telemetry receivers suitable for this
purpose should be used (such as the DTRX3 fitted with the DTCOAX board).
After completing the operation, close the bottom of the base and reconnect the base to the system.
Connections
The installation must be carried out only by qualified technical staff: an improper connection of the
peripheral units may cause the remote control to be isolated from the rest of the system.
RS485 communication line termination to receiver
The DCIR remote control uses the communication standard RS485.
The RS485 standard is an updating of RS422-A, the same signals level of which are used to make the half-
duplex multi point communications easier.
The standard, particularly immune to electromagnetic noises, consists of a balanced transmission on two wires,
1200m max length, with 24 AWG cable, signal generation 6 dB.
The following configurations are possible:
•
Point – point
•
Multipoint
Point - point connection
The termination resistances of the appliances placed to the ends of the RS485 line must be connected
Multipoint connection
The termination resistances of the appliances placed to the ends of the RS485 line must be connected.
The termination resistances of the appliances placed along the RS485 line, not at its ends, have to be not
connected.
TERMINATION RESISTANCE
TERMINATION RESISTANCES
DCIR
DCIR
DTMRX1
DTMRX1
DCIR