Mitsubishi Electric FX2N-32CAN, Руководство по обучению

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A.5
PLC Components Glossary
The following table describes the meaning and functionality of the single components und parts
of a Mitsubishi PLC.
Appendix PLC Components Glossary
Training Manual GX IEC Developer A - 17
Component Description
Connection for
expansion
adapter boards
Optional expansion adapter boards can be connected to this interface. A variety of differ-
ent adapters are available for all FX lines (except the FX
2NC
). These adapters extend the
capabilities of the controllers with additional functions or communications interfaces. The
adapter boards are plugged directly into the slot.
Connection for pro-
gramming units This connection can be used for connecting the FX-20P-E hand-held programming unit or
an external PC or notebook with a programming software package (e.g. GX Developer).
EEPROM
Read/write memory in which the PLC program can be stored and read with the program-
ming software. This solid-state memory retains its contents without power, even in the
event of a power failure, and does not need a battery.
Memory cassette slot
Slot for optional memory cassettes. Inserting a memory cassette disables the controller’s
internal memory – the controller will then only execute the program stored in the cassette.
Extension bus
Both additional I/O expansion modules and special function modules that add additional
capabilities to the PLC system can be connected here. See Chapter 6 for an overview of
the available modules.
Analog
potentiometers The analog potentiometers are used for setting analog setpoint values. The setting can be
polled by the PLC program and used for timers, pulse outputs and other functions.
Service power supply
The service power supply (not for FX
2NC
ans FX
3UC
) provides a regulated 24V DC power
supply source for the input signals and the sensors. The capacity of this power supply
depends on the controller model (e.g. FX
1S
, FX
1N
and FX
3G
: 400mA; FX
2N
-16M
쏔
-
쏔쏔
through FX
2N
-32M
쏔
-
쏔쏔
: 250 mA, FX
2N
-48M
쏔
-
쏔쏔
through FX
2N
-64M
쏔
-
쏔쏔
: 460 mA)
Digital inputs
The digital inputs are used for inputting control signals from the connected switches, but-
tons or sensors. These inputs can read the values ON (power signal on) and OFF (no
power signal).
Digital outputs
You can connect a variety of different actuators and other devices to these outputs,
depending on the nature of your application and the output type.
LEDs for indicating
the input status
These LEDs show which inputs are currently connected to a power signal, i.e. a defined
voltage. When a signal is applied to an input the corresponding LED lights up, indicating
that the state of the input is ON.
LEDs for indicating
the output status
These LEDs show the current ON/OFF states of the digital outputs. These outputs can
switch a variety of different voltages and currents depending on the model and output
type.
LEDs for indicating
the operating status
The LEDs RUN, POWER and ERROR show the current status of the controller. POWER
shows that the power is switched on, RUN lights up when the PLC program is being exe-
cuted and ERROR lights up when an error or malfunction is registered.
Memory battery
The battery protects the contents of the MELSEC PLC’s volatile RAM memory in the
event of a power failure (FX
2N
, FX2
NC
and FX
3U
only). It protects the latched ranges for
timers, counters and relays. In addition to this it also provides power for the integrated
real-time clock when the PLC’s power supply is switched off.
RUN/STOP switch
MELSEC PLCs have two operating modes, RUN and STOP.
The RUN/STOP switch allows you to switch between these two modes manually. In RUN
mode the PLC executes the program stored in its memory. In STOP mode program execu-
tion is stopped and it is possible to program the controller.