Communications Capabilities - Siemens SIMATIC S5-90U System Manual

S5-90U/S5-95U
Communications
Complex applications sometimes make it necessary for the programmable controller to communicate
with other PLCs or peripherals. SIMATIC S5 PLCs offer two possibilities:
• Point-to-point connections or
• Networking via SINEC L1 and SINEC L2 LANs.
SINEC L2 bus
Printers
Computers
Printers
Computers
Point-to-point connections are the ideal solution for connecting up only two devices. They are
both economical and very efficient. The integral 20 mA (TTY) interface (programmer interface) can
be used to connect a programmer (PG) or operator panel (OP).
The optional second serial interface (20 mA) of the S5-95U permits the simultaneous connection of
programmers and operator panels. Additionally, the following devices can be linked:
• Other SIMATIC PLCs (SINEC L1 protocol, S5-95U as point-to-point master)
• Siemens devices (3964(R) protocol) or
• Third-party devices (ASCII protocol).
Communications processors (CPs) offer additional communications possibilities.
If more than two devices are to be interconnected, the use of a LAN is recommendable. The low-
cost SINEC L1 LAN for applications that are not critical with regard to time can connect devices
over distances of up to 50 km via a four-wire cable. It can easily be expanded for a maximum of 31
stations.
S5-90U and S5-95U programmable controllers can be connected as slaves to this LAN via the
integral 20 mA (TTY) interface (programmer interface) or the CP 521 SI communications processor.
The S5-95U is optionally available with SINEC L2 interface. SINEC L2 is the LAN type required for
the lower and medium-range cell and field levels in industrial environments and conforms to the
PROFIBUS standard (DIN 19245).
The open LAN architecture permits the connection of non-Siemens field devices. However, it is also
possible to link S5-95U PLCs only.
The S5-95U with SINEC L2 interface can communicate both as active and passive station on the
bus.
EWA 4NEB 812 6115-02b
CP
CP
SINEC L2 interface optional
Figure 1-2. Communications Capabilities
S5-90U
20mA interface
S5-95U
20mA interfaces
(2nd interface optional)
System Description
SINEC L1 bus
PG
OP
PG
OP
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