Connections (Point-To-Point Connections) - Siemens SIMATIC PG 760 Manual

3.4 PG 760 Connections (Point-to-Point Connections)
Point-to-Point
In this section, you will learn how to connect your PG 760 to a programming
Connection
device or programmable controller using a point-to-point connection.
You can establish a point-to-point connection by connecting the PG 760 to
another programming device or a programmable controller via:
Suggestions for Reliable data transfer depends on several factors. The data transfer rate you
Configuring TTY can achieve depends on the distance, the type of cable, the type of interface
(20 mA) Interfaces and any interference present.
Rules
You can reduce interference by choosing the right transmission cable and
connecting it properly, and observing the following guidelines:
Note
The contaminating field of the interference source decreases exponentially
with the distance.
PG 760 Programming Device
C79000-G7076-C761-01
a V.24 connection.
a TTY connection.
Use a shielded cable with a low surge impedance (< 130
capacitance (< 90 pF/m). Twisted-pair cables enhance noise immunity
due to inductance. A low surge impedance results in reduced voltage
excursions and shorter charge reversal times. The larger the conductor
cross-section, the lower the surge impedance for the same length of cable.
The shorter the transmission link, the higher the maximum possible data
transfer rate.
If there is an active sender and an active receiver at the same end of the
transmission link, the sequence of access priority to the transmission
circuit must be taken into account in order to achieve the longest possible
transmission link.
Signal lines and power lines must not be run together. Signal lines must
be installed as far away as possible from strong interference sources
(for example, 400 V three-phase power cables).
The active TTY interface with 12 V no-load voltage has been tested on a
1000 m (3300 ft.) long cable at a transmission rate of 9600 bps in a
normal noisy environment (field strength < 3 V/m or 1 V/ft.). If a
shielded LiYCY 5x1x0.14 is used, reliable transmission is possible over a
distance of up to 1000 m (3300 ft.). The AS511 protocol (only one
transmitter at a time) was used for testing.
Installing and Operating the PG 760
/ km) and low
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