Siemens SIMATIC S5-115U, User Manual

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Technical Description S5-115U Manual
Central Processing Unit (CPU)
The central processing unit reads in input signal states, processes the control program, and
controls outputs. In addition to program scanning functions, the CPU provides internal flags,
timers and counters. You can preset the restart procedure and diagnose errors using the CPU's
LEDs. Use the Overall Reset switch on the CPU to delete the RAM contents.
Use a programmer or a memory submodule to transfer the control program to the CPU.
Communications Processors (CP)
Communications processors can be used in the S5-115U for communication between man and
machine and between machines. Communications processors perform the following func-
tions:
•
operator monitoring and control of machine functions or process sequences
• reporting and listing of machine and process states
You can connect various peripheral devices to these processors, e.g. printers, keyboards, CRTs
and monitors as well as other controllers and computers.
Input/Output Modules (I/Os)
•
Digital input modules adapt digital signals, e.g. from pressure switches or BERO®
proximity switches, to the internal signal level of the S5-115U.
• Digital output modules convert the internal signal level of the S5-115U into digital process
signals, e.g. for relays or solenoid valves.
• Analog input modules adapt analog process signals, e.g. from transducers or resistance
thermometers, to the S5-115U, which functions digitally.
• Analog output modules convert internal digital values of the S5-115U to analog process
signals, e.g. for speed controllers.
Interface Modules (IM)
The S5-115U is installed on mounting racks with a specific number of mounting locations
(slots). A configuration comprising power supply, CPU, and input/output modules is called a
central controller. If the slots on the central controller's mounting rack are insufficient, you
can install expansion units (systems without CPUs) on additional mounting racks. Interface
modules connect an expansion unit to a central controller.
Mounting Racks
A mounting rack consists of an aluminium rail to which all the modules are fastened mechani-
cally. It has one or two backplanes that connect the modules to each other electrically.
Serial Interface
You can connect the following at this interface:
•
Programmer
• Operator panel
• SINEC L1 bus terminal
Memory submodule
Battery compartment
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EWA 4NEB 811 6130-02b