Mitsubishi Electric Melsec A Series User manual

MELSECASeries
Programmable Controllers
User's Manual
(Hardware)
AnN/AnA/AnUCPU
MITSUBISHI ELECTRIC
MITSUBISHI ELECTRIC
01 08 2003
IB(NA)66542
Version E
INDUSTRIAL AUTOMATION

A-1
zSAFETY PRECAUTIONS z
(Read these precautions before using.)
When using Mitsubishi equipment, thoroughly read this manual and the
associated manuals introduced in this manual.
Also pay careful attention to safety and handle the module properly.
These z
zz
zSAFETY PRECAUTIONS z
zz
zclassify the safety precautions into two
categories: "DANGER" and "CAUTION".
Procedures which may lead to a dangerous condition
and cause death or serious injury if not carried out
properly.
Procedures which may lead to a dangerous condition
and cause superficial to medium injury, or physical
damage only, if not carried out properly.
Depending on circumstances, procedures indicated by CAUTION may
also be linked to serious results.
In any case, it is important to follow the directions for usage.
Store this manual in a safe place so that you can take it out and read it
whenever necessary. Always forward it to the end user.
[DESIGN PRECAUTIONS]
DANGER
Install a safety circuit external to the PLC that keeps the entire system
safe even when there are problems with the external power supply or the
PLC module. Otherwise, trouble could result from erroneous output or
erroneous operation.
(1) Outside the PLC, construct mechanical damage preventing interlock
circuits such as emergency stop, protective circuits, positioning upper
and lower limits switches and interlocking forward/reverse operations.
CAUTION
DANGER

A-2
[DESIGN PRECAUTIONS]
DANGER
(2) When the PLC detects the following problems, it will stop calculation
and turn off all output in the case of (a). In the case of (b), it will stop
calculation and hold or turn off all output according to the parameter
setting.
Note that the AnS series module will turn off the output in either of
cases (a) and (b).
(a) The power supply module has over current
protection equipment and over voltage protection equipment.
(b) The PLC CPUs self-diagnosis functions, such as the watch dog
timer error, detect problems.
In addition, all output will be turned on when there are problems that
the PLC CPU cannot detect, such as in the I/O controller. Build a fail
safe circuit exterior to the PLC that will make sure the equipment
operates safely at such times. See section 9.1 of this manual for
example fail safe circuits.
(3) Output could be left on or off when there is trouble in the outputs
module relay or transistor. So build an external monitoring circuit that
will monitor any single outputs that could cause serious trouble.
When overcurrent which exceeds the rating or caused by short-circuited
load flows in the output module for a long time, it may cause smoke or
fire. To prevent this, configure an external safety circuit, such as fuse.
Build a circuit that turns on the external power supply when the PLC main
module power is turned on. If the external power supply is turned on
first, it could result in erroneous output or erroneous operation.
When a data link results in a communication error, the faulty station
changes in operating status depending on the used data link type.
(1) For the data link data, the data prior to the communication error will be
held.
(2) The MELSECNET (II,/B,/10) remote I/O station will turn all output off.
(3) The MELSECNET/MINI-S3 remote I/O station will hold the output or
turn all output off depending on the E.C. remote setting.
Refer to the data link manuals regarding the method for setting the
communication problem station and the operation status when there are
communication problem.

A-3
[DESIGN PRECAUTIONS]
DANGER
When connecting a peripheral device to the CPU module or connecting a
personal computer or the like to the intelligent function module to
exercise control (data change) on the running PLC, configure up an
interlock circuit in the sequence program to ensure that the whole
system will always operate safely.
Also before exercising other control (program change, operating status
change (status control)) on the running PLC, read the manual carefully
and fully confirm safety.
Especially for the above control on the remote PLC from an external
device, an immediate action may not be taken for PLC trouble due to a
data communication fault.
In addition to configuring up the interlock circuit in the sequence program,
corrective and other actions to be taken as a system for the occurrence of
a data communication fault should be predetermined between the external
device and PLC CPU.
When configuring a system, do not leave any slots vacant on the base.
Should there be any vacant slots, always use a blank cover (A1SG60) or
dummy module (A1SG62).
When the extension base A1S52B, A1S55B or A1S58B is used, attach the
dustproof cover supplied with the product to the module installed in slot
0.
If the cover is not attached, the module's internal parts may be
dispersed when a short-circuit test is performed or
overcurrent/overvoltage is accidentally applied to the external I/O area.
CAUTION
Do not bunch the control wires or communication cables with the main
circuit or power wires, or install them close to each other. They should
be installed 100 mm (3.94 inch) or more from each other. Not doing so
could result in noise that would cause erroneous operation.
When controlling items like lamp load, heater or solenoid valve using an
output module, large current (approximately ten times greater than that
present in normal circumstances) may flow when the output is turned
OFF to ON.
Take measures such as replacing the module with one having sufficient
rated current.

A-4
[INSTALLATION PRECAUTIONS]
CAUTION
Use the PLC in an environment that meets the general specifications
contained in this manual. Using this PLC in an environment outside the
range of the general specifications could result in electric shock, fire,
erroneous operation, and damage to or deterioration of the product.
Hold down the module loading lever at the module bottom, and securely
insert the module fixing latch into the fixing hole in the base unit.
Incorrect loading of the module can cause a malfunction, failure or drop.
When using the PLC in the environment of much vibration, tighten the
module with a screw.
Tighten the screw in the specified torque range. Undertightening can
cause a drop, short circuit or malfunction. Overtightening can cause a
drop, short circuit or malfunction due to damage to the screw or module.
When installing extension cables, be sure that the connectors of base
unit are installed correctly. After installation, check them for looseness.
Poor connections could cause an input or output failure.
Correctly connect the memory cassette installation connector to the
memory cassette. After installation, be sure that the connection is not
loose. A poor connection could cause an operation failure.
Completely turn off the external power supply before loading or
unloading the module. Not doing so could result in electric shock or
damage to the product.
Do not directly touch the module's conductive parts or electronic
components. Touching the conductive parts could cause an operation
failure or give damage to the module.

A-5
[WIRING PRECAUTIONS]
DANGER
Completely turn off the external power supply when installing or placing
wiring. Not completely turning off all power could result in electric shock
or damage to the product.
When turning on the power supply or operating the module after
installation or wiring work, be sure that the module's terminal covers are
correctly attached. Not attaching the terminal cover could result in
electric shock.
CAUTION
Be sure to ground the FG terminals and LG terminals to the protective
ground conductor. Not doing so could result in electric shock or
erroneous operation.
When wiring in the PLC, be sure that it is done correctly by checking the
product's rated voltage and the terminal layout. Connecting a power
supply that is different from the rating or incorrectly wiring the product
could result in fire or damage.
Do not connect multiple power supply modules in parallel. Doing so
could cause overheating, fire or damage to the power supply module.
External connections shall be crimped or pressure welded with the
specified tools, or correctly soldered. Imperfect connections could result
in short circuit, fires, or erroneous operation.
Tighten the terminal screws with the specified torque. If the terminal
screws are loose, it could result in short circuits, fire, or erroneous
operation. Tightening the terminal screws too far may cause damages to
the screws and/or the module, resulting in fallout, short circuits, or
malfunction.
Be sure there are no foreign substances such as sawdust or wiring
debris inside the module. Such debris could cause fires, damage, or
erroneous operation.
The module has an ingress prevention label on its top to prevent foreign
matter, such as wire offcuts, from entering the module during wiring.
Do not peel this label during wiring.
Before starting system operation, be sure to peel this label because of
heat dissipation.

A-6
[STARTUP AND MAINTENANCE PRECAUTIONS]
DANGER
Do not touch the terminals while power is on.
Doing so could cause shock or erroneous operation.
Correctly connect the battery.
Also, do not charge, disassemble, heat, place in fire, short circuit, or
solder the battery. Mishandling of battery can cause overheating or
cracks which could result in injury and fires.
Switch all phases of the external power supply off when cleaning the
module or retightening the terminal or module mounting screws. Not
doing so could result in electric shock.
Undertightening of terminal screws can cause a short circuit or
malfunction. Overtightening of screws can cause damages to the screws
and/or the module, resulting in fallout, short circuits, or malfunction.

A-7
[STARTUP AND MAINTENANCE PRECAUTIONS]
CAUTION
The online operations conducted for the CPU module being operated,
connecting the peripheral device (especially, when changing data or
operation status), shall be conducted after the manual has been carefully
read and a sufficient check of safety has been conducted.
Operation mistakes could cause damage or problems with of the
module.
Do not disassemble or modify the modules.
Doing so could cause trouble, erroneous operation, injury, or fire.
Use any radio communication device such as a cellular phone or a PHS
phone more than 25cm (9.85 inch) away from the PLC.
Not doing so can cause a malfunction.
Switch all phases of the external power supply off before mounting or
removing the module. If you do not switch off the external power supply,
it will cause failure or malfunction of the module.
Do not drop or give an impact to the battery installed in the module.
Otherwise the battery will be broken, possibly causing internal leakage
of electrolyte. Do not use but dispose of the battery if it has fallen or an
impact is given to it.
Always make sure to touch the grounded metal to discharge the
electricity charged in the electricity charged in the body, etc., before
touching the module.
Failure to do say cause a failure or malfunctions of the module.
[DISPOSAL PRECAUTIONS]
CAUTION
z
zz
zWhen disposing of this product, treat it as industrial waste.
[TRANSPORTATION PRECAUTIONS]
CAUTION
z
zz
zWhen transporting lithium batteries, make sure to treat them based on
the transport regulations. (Refer to Chapter 7 for details of the controlled
models.)

A-8
REVISIONS
*The manual number is given on the bottom right of the front cover.
Print Date *Manual Number Revision
Mar., 1995 IB(NA) 66542-A First edition
Jan., 1996 IB(NA) 66542-B
Sep., 1998 IB(NA) 66542-C Correction
SAFETY PRECAUTIONS, 4.5.2
Addition
SPECIFICATIONS, PERFORMANCE
SPECIFICATIONS, EMC STANDARDS,
LOW-VOLTAGE INSTRUCTION
Deletion
I/O MODULE SPECIFICATIONS AND
CONNECTIONS
Dec., 2002 IB(NA) 66542-D Equivalent to Japanese version G
Addition
Chapter 5
Partial corrections
SAFETY PRECAUTIONS, 1.1, 2.1.1,
2.1.2, 2.1.3, Chapter 3, 4.1.3, 4.2, 4.3.1,
4.3.2,4.3.3, 4.5.2, Chapter 6
Aug., 2003 IB(NA) 66542-E Addition
Chapter 7
Partial corrections
SAFETY PRECAUTIONS, Section 6.1
Japanese Manual Version IB(NA)68438-H
This manual confers no industrial property rights or any rights of any other kind,
nor does it confer any patent licenses. Mitsubishi Electric Corporation cannot be
held responsible for any problems involving industrial property rights which may
occur as a result of using the contents noted in this manual.
©1995 Mitsubishi Electric Corporation

A-9
This manual describes EMC DIRECTIVE AND LOW-VOLTAGE INSTRUCTION,
the handling precautions, and error codes of the following CPUs:
z
zz
zA1NCPU(P21(-S3)/R21), A2NCPU(P21(-S3)/R21), A2NCPU(P21/R21)-S1(-S4),
A3NCPU(P21(-S3)/R21) (abbreviated to AnNCPU in this manual)
z
zz
zA2ACPU(P21(-S3)/R21), A2ACPU(P21/R21)-S1(-S4), A3ACPU(P21(-S3)/R21)
(abbreviated to AnACPU in this manual)
z
zz
zA2UCPU, A2UCPU-S1, A3UCPU, A4UCPU (abbreviated to AnUCPU in this
manual)
AnNCPU, AnACPU, and AnUCPU are generically abbreviated to CPU in this
manual.
Manuals
The manuals related to these CPUs are listed below.
Refer to the following manuals when necessary.
Detailed manuals
z
zz
zA1N/A2N(S1)/A3NCPU User's Manual (IB-66543)
This manual describes the performance, functions, handling, etc., of the A1NCPU,
A2NCPU(S1), and A3NCPU, and the specifications and handling for the memory
cassette, power supply module, and base unit.
z
zz
zA2A/A3ACPU User's Manual (IB-66544)
This manual describes the performance, functions, handling, etc., of the
A2ACPU(S1) and A3ACPU, and the specifications and handling of the memory
cassette, power supply module, and base unit.
z
zz
zA2U(S1)/A3U/A4UCPU User's Manual (IB-66436)
This manual describes the performance, functions, handling, and so forth of
A2UCPU(S1), A3UCPU, A4UCPU, and the specifications and handling of the
memory cassette, power supply module, and base unit.
Related manuals
z
zz
zACPU/QCPU-A(A mode) Programming Manual (Fundamentals) (IB-66249)
This manual describes programming methods required to create programs,
device names, parameters, types of program, configuration of the memory area,
etc.
z
zz
zACPU/QCPU-A(A mode) Programming Manual (Common Instructions)
(IB-66250)
This manual describes how to use the sequence instructions, basic instructions,
application instructions and micro-computer programs.

A-10
z
zz
zAnSHCPU/AnACPU/AnUCPU/QCPU-A(A mode) Programming Manual
(Dedicated Instructions) (IB-66251)
This manual describes the instructions that are expanded for dedicated use with
the A2ACPU(S1), A3ACPU, A2UCPU(S1), A3UCPU, and A4UCPU.
z
zz
zAnACPU/AnUCPU Programming Manual (AD57 Control Instructions)
(IB-66257)
This manual describes sequence program instructions used to control the
AD57(S1)/AD58 CRT/LCD controllers with the A2ACPU(S1), A3ACPU,
A2UCPU(S1), A3UCPU, and A4UCPU.
z
zz
zAnACPU/AnUCPU Programming Manual (PID Control Instructions)
(IB-66258)
This manual describes sequence program instructions used to execute PID
control with the A2ACPU(S1), A3ACPU, A2UCPU(S1), A3UCPU, and A4UCPU.
z
zz
zBuilding Block I/O Module User's Manual (IB-66140)
This manual describes the specifications of the building block I/O module.

A-11
CONTENTS
1.SPECIFICATIONS...............................................................................................................1
1.1 SPECIFICATIONS..........................................................................................................1
2.Performance Specifications.............................................................................................2
2.1 CPU Module Performance Specifications....................................................................2
2.1.1 AnNCPUModule Performance Specifications.....................................................2
2.1.2 AnACPU Module performance specifications......................................................4
2.1.3 AnUCPUModule Performance Specifications.....................................................7
3.EMC DIRECTIVE AND LOW-VOLTAGE INSTRUCTION.............................................9
3.1 Requirements for Compliance to EMC Directive (89/336/EEC).................................9
3.1.1 EMC standards........................................................................................................9
3.1.2 Installation inside the control cabinet...................................................................10
3.1.3 Cables.................................................................................................................... 12
3.1.4 Power supply module...........................................................................................16
3.1.5 Ferrite core............................................................................................................16
3.1.6 Noise filter (power supply line filter).....................................................................17
3.2 Requirement to Conform to the Low-Voltage Instruction.........................................18
3.2.1 Standard applied for MELSEC-A........................................................................ 18
3.2.2 Precautions when using the A series..................................................................18
3.2.3 Power supply.........................................................................................................19
3.2.4 Control box............................................................................................................20
3.2.5 Module installation................................................................................................ 21
3.2.6 Grounding..............................................................................................................21
3.2.7 External wiring.......................................................................................................21
4.LOADING AND INSTALLATION.................................................................................... 22
4.1 Installing Modules.........................................................................................................22
4.1.1 Precautions for handling of modules ..................................................................22
4.1.2 Installation environment........................................................................................22
4.1.3 Precautions relating to the installation of the base unit .....................................23
4.2 The view of a Fail-safe Circuit.....................................................................................26
4.3 Power Supply Connection...........................................................................................30
4.3.1 Performance Specification for Power Supply Modules.....................................30
4.3.2 Part identification and setting of Power SupplyModule....................................34
4.3.3 Power Supply Connection................................................................................... 39
4.4 Precaution when Connecting the Uninterruptive Power Supply (UPS)..................42
4.5 Part Identification..........................................................................................................43
4.5.1 Part identification of AnNCPU, AnACPU, and AnUCPU..................................43
4.5.2 Part identification of AnNCPUP21/R21, AnACPUP21/R21.............................48
5.I/O MODULE SPECIFICATIONS AND CONNECTIONS............................................ 52
5.1 Input Modules...............................................................................................................52
5.1.1 Input module specifications..................................................................................52
5.1.2 Input module connections....................................................................................56
5.2 Output Modules............................................................................................................63
5.2.1 Output module specifications..............................................................................63
5.2.2 Output module connections.................................................................................69
5.3 Input/Output Combined Modules................................................................................79

A-12
5.3.1 Input/output combined module specifications.....................................................79
5.3.2 Input/output combined module connections.......................................................81
6.ERROR CODES................................................................................................................84
6.1 Error Code List for AnNCPU........................................................................................84
6.2 Error Code List for AnACPU........................................................................................94
6.3 Error Code List for AnUCPU.....................................................................................112
7. TRANSPORTATION PRECAUTIONS....................................................................... 134
7.1 Controlled Models...................................................................................................... 134
7.2 Transport Guidelines................................................................................................. 134

1
1. SPECIFICATIONS
1.1 SPECIFICATIONS
Table 1.1 General specification
Item Specifications
Ambient operating
temperature 0 to 50 °C
Ambient storage
temperature −20 to 75 °C
Ambient operating
humidity 10 to 90 % RH, No-condensing
Ambient storage
humidity 10 to 90 % RH, No-condensing
Frequency Acceleration Amplitude
No. of
sweeps
10 to 57Hz  0.075mm
(0.003in.)
Under
intermittent
vibration 57 to 150Hz 9.8m/s2
10 to 57Hz  00.35mm
(0.001in.)
Vibration
resistance
Conforming to
JIS B 3502,
IEC 61131-2 Under
continuous
vibration 57 to 150Hz 4.9m/s2
10 times
each in
X, Y, Z
directions
(for 80min.)
Shock resistance
Conforming to JIS B 3502, IEC 61131-2 (147 m/s
2
, 3 times in each of 3 directions X Y
Z)
Operating
ambience No corrosive gases
Operating
elevation *3 2000m (6562ft.) max.
Installation location Control panel
Over voltage
category *1 II max.
Pollution level *2 2 max.
*1 : This indicates the section of the power supply to which the equipment is
assumed to be connected between the public electrical power distribution
network and the machinery within premises. Category II applies to equipment for
which electrical power is supplied from fixed facilities. The surge voltage
withstand level for up to the rated voltage of 300 V is 2500 V.
*2 : This index indicates the degree to which conductive material is generated in
terms of the environment in which the equipment is used. Pollution level 2 is
when only non-conductive pollution occurs. A temporary conductivity caused by
condensing must be expected occasionally.
*3 : Do not use or store the PC in the environment when the pressure is higher than
the atmospheric pressure at sea level. Otherwise, malfunction may result. To
use the PC in high-pressure environment, contact your nearest Mitsubishi
representative.

2
2. Performance Specifications
2.1 CPU Module Performance Specifications
2.1.1 AnNCPU Module Performance Specifications
Table 2.1 shows the memory capacities of the CPU modules and the performance
of their devices. Table 2.1 Performance Specifications
Performance
Item A1NCPU A2NCPU A2NCPU-S1 A3NCPU
Control system Stored program, repeated operation
I/O control mode Refresh / direct mode selectable
Programming language Language dedicated to sequence control. (Combined use of relay symbol type, logic symbolic language and
MELSAP-II(SFC)*1)
Sequence
instructions 26
Basic
instructions 131 132
Instruction
(types) Application
instruction 103 107 110
Processing speed
(Sequence instruction)
(µsec/step)
Direct mode : 1.0 to 2.3
Refresh mode : 1.0
I/O points 256 points
(X/Y0 to FF) 512 points (X/Y0 to 1FF) 1024 points (X/Y0 to 3FF) 2048 points (X/Y0 to 7FF)
Watch dog timer (WDT)
(msec) 10 to 2000ms
Capacity of installed memory cassette
Memory capacity Max. 16k bytes Max.448k bytes
Main
sequence
program Max. 6k steps Max.14k steps Max. 30k steps
Program
capacity Sub-sequence
program Absent Max. 30k steps
*1 The SFC language cannot be used with an A1NCPU.

3
Table 2.1 Performance Specifications (Continued)
Performance
Item A1NCPU A2NCPU A2NCPU-S1 A3NCPU
Self-diagnosis Watchdog error supervision Memory error detection, CPU error detection, I/O error detection, battery
error detection, etc.
Operation mode at error
occurrence Stop or continue selectable
Output mode a switching at
STOP ÆRUN Selection of re-output of operation state before STOP (default)/output after operation execution
Starting method at RUN Initial start (Automatic restart when "RUN" switch is moved to ON position
at power-on, at power restoration after power failure)
Clock function
Year, month, day, hour, second, and day of the week (automatic leap year
recognition) Accuracy:
-3.9 to + 0.8s (TYP. -1.1s) /d at 0°C
-1.8 to + 1.0s (TYP. -0.2s) /d at 25°C
-8.5 to + 0.7s (TYP. -4.0s) /d at 55°C
Latch (power failure
compensation) range Defaults to L1000 to 2047 (Latch range can be set for L, B, T, C, D and W relays.)
X0 to FF X0 to 1FF X0 to 3FF X0 to 7FF
Remote RUN/Pause contact One RUN contact and one PAUSE contact can be set. It is not possible
Allowable momentary power
failure time 20 msec Depends on used power supply module
5 VDC internal power
consumption (A)
A1NCPU :0.53
A1NCPUP21(S3)
:1.23
A1NCPUR21
:1.63
A2NCPU :0.73
A2NCPUP21(S3)
:1.38
A2NCPUR21
:1.78
A2NCPU-S1
:0.73
A2NCPUP21-S1
(S4) :1.38
A2NCPUR21-S1
:1.78
A3NCPU :0.90
A3NCPUP21(S3)
:1.55
A3NCPUR21
:1.95
Weight kg
A1NCPU :1.45
A1NCPUP21(S3)
:1.75
A1NCPUR21
:1.75
A2NCPU :0.62
A2NCPUP21(S3)
:0.92
A2NCPUR21
:0.92
A2NCPU-S1
:0.62
A2NCPUP21-S1
(S4) :0.92
A2NCPUR21-S1
:0.92
A3NCPU :0.65
A3NCPUP21(S3)
:0.95
A3NCPUR21
:0.95
External dimensions mm (in)
250(H) ×135(W)
×121(D)
(9.84 ×5.31
×4.76)
250(H) ×79.5(W) ×121(D) (9.84 ×3.13 ×4.76)

4
2.1.2 AnACPU Module performance specifications
Table 2.2 shows the performance specifications of the AnACPU module. Since the
valid range for setting each device differs, use caution when a previous system FD,
peripheral devices or an AnACPU compatible system FD are used.
Table 2.2 CPU Module Performance Specifications
Performance
Item A2ACPU A2ACPU-S1 A3ACPU Remarks
Control system Stored program, repeated operation
I/O control method Refresh method Instructions to enable partial direct I/O are
available.
Language dedicated to sequence control
Programming language Combined use of relay symbol type, logic symbolic
language and MELSAP-II(SFC)
Processing speed
(Sequence instruction) A2A (S1) : 0.2 to 0.4 µs/STEP A3A : 0.15 to 0.3 µs/STEP
Sequence
instruction 25 types
Basic,
application
instruction 233 types 235 types
Instruction
Dedicated
instruction 200 types
Constant scan (program
start at specified
intervals)
Can be set between 10 msec and 190 msec in 10
msec increments Set in special register D9020.
Memory
capacity Max. 448k bytes Max. 768k bytes
Memory
capacity
and
memory
type
Memory
type
(Memory
cassette
type)
A3NMCA-0 to A3NMCA-56 A3NMCA-0 to A3NMCA-56
*A3AMCA-96
Refer to Section 7 for
detalls on memory
cassette.
Battery back up.
POINT
* Memory cassette A3AMCA-96 is compatible with CPUs of the following
versions and later versions.
•A3ACPU Version BM
•A3ACPUP21 Version BL
•A3ACPUR21 Version AL
Example)
BM
Software version
Hardware version

5
Table 2.2 CPU Module Performance Specifications (continued)
Performance
Item A2ACPU A2ACPU-S1 A3ACPU Remarks
6k steps
Main sequence program
capacity (Can be set to max. 14k steps (Can be set to
max. 30k steps)
Set in parameters.
Sub-sequence program
capacity Absent 0 to 30k steps can be set. Set in parameters.
I/O points 512 points 1024 points 2048 points
The number of points
which can be used for
accessibility to actual
I/O modules.
STOP →RUN output
mode Selection of re-output of operation state before STOP (default)/output after operation execution Set in parameters.
Self-diagnostic functions Watchdog error timer (watchdog timer 200 msec fixed) Memory error detection, CPU error detection, I/O error
detection, battery error detection, etc.
Starting method at RUN Automatic restart when "RUN" switch is moved to ON
position (initial start)
Allowable momentary
power failure time Depends on used power supply module
Latch (power failure
compensation) range
Using parameter setting, M, L, and S relays 0 to 8191,
can be set in latch relay as L0 to L8191 (defaults to
L1000 to L2047)
Set range in
parameters.
Remote RUN/PAUSE
contact
RUN/PAUSE contact point can be set by the
parameter settings for A2A, A2A-S1, and A3 within the
following range.
A2A: X0 to X1FF, A2A-S1: X0 to X3FF, and A3A: X0
to X7FF.
Operation mode at the
time of error I/O, special function module error: Stop, Operation error: continue Can be changed to operation error stop.
Clock function
Year, month, day, hour, minute, second, day of the week
(leap year is automaticallyidentified.)
Accuracy
-2.3 to + 4.4s (TYP. +1.8s) /d at 0°C
-1.1 to + 4.4s (TYP. +2.2s) /d at 25°C
-9.6 to + 2.7s (TYP. -2.4s) /d at 55°C
Step RUN
yExecution per instruction
yExecution per circuit ladder block
yExecution according to loop count and step interval
specification
yExecution according to loop count and break point
specification
yExecution according to device status
Interrupt
processing
Interrupt program can be run in response to a signal
from an interrupt unit or by a constant-cycle interrupt
signal.
Other
functions
Data link Data link system incorporating local PCs and/or
remote I/O can be constructed.

6
Table 2.2 CPU Module Performance Specifications (continued)
Performance
Item A2ACPU A2ACPU-S1 A3ACPU Remarks
Current consumption
(A)
A2ACPU : 0.4
A2ACPUP21(S3)
: 1.0
A2ACPUR21
: 1.4
A2ACPU-S1: 0.4
A2ACPUP21-S1
(S4) : 1.0
A2ACPUR21-S1
: 1.4
A3ACPU : 0.6
A3ACPUP21(S3)
: 1.0
A3ACPUR21
: 1.6
Differs according to
memory cassette.
Weight kg
A2ACPU : 0.7
A2ACPUP21(S3)
: 0.9
A2ACPUR21
: 0.9
A2ACPU-S1: 0.7
A2ACPUP21-S1
(S4) : 0.9
A2ACPUR21-S1
: 0.9
A3ACPU : 0.7
A3ACPUP21(S3)
: 0.9
A3ACPUR21
: 1.0
External dimensions
mm (in) 250(H) ×79.5(W) ×121(D) (9.84 ×3.13 ×4.76)

7
2.1.3 AnUCPU Module Performance Specifications
This section explains the performance specifications and devices of the AnUCPU.
Table 2.3 Performance Specifications
Performance
Item A2UCPU A2UCPU-S1 A3UCPU A4UCPU Remarks
Control system Stored program, repeated operation
I/O control method Refresh method
Instructions to
enable partial
direct I/O are
available.
Language dedicated to sequence control
Programming language Combined use of relay symbol type, logic symbolic
language and MELSAP-II (SFC)
Processing speed
(Sequence
instruction)
(µsec/step)
0.2 0.15
Sequence
instruction 25
Basic,
application
instruction 233 235
Inst-ru
ction
(types) Dedicated
instruction 204
Constant scan
(program start at
specified intervals)
Can be set between 10 msec and 190 msec in 10 msec
increments Set in special register D9020.
Memory capacity Capacity of installed memory cassette
(Max. 448 kbytes)
Capacity of installed
memory cassette
(Max. 1024 kbytes)
Main
sequence
program Max. 14k steps Max. 30k steps
Program
capacity Sub-seque
nce
program Absent Max. 30k
steps Max. 30k steps ×3
Set in
parameters.
I/O device points 8192 points (X/Y0 to 1FFF) The number of points usable in
the program
I/O points 512 points (X/Y0 to
1FF)
1024 points
(X/Y0 to
3FF)
2048 points
(X/Y0 to
7FF)
4096 points
(X/Y0 to
FFF)
The number of
points which can
be used for
accessibility to
actual I/O
modules