Siemens Simatic S7-1500 User manual

CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
SIMATIC
S7-1500
CPU 1518
-4 PN/DP MFP
(6ES7518
-4AX00-1AB0)
Equipment Manual
07/2021
A5E40882737
-AB
Preface
Documentation guide
1
Product overview
2
Connecting up
3
Interrupts, error messages,
diagnostics and system
alarms
4
Technical specifications
5
Dimensional drawing
A

Siemens AG
Digital Industries
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A5E40882737-AB
Ⓟ
07/2021 Subject to change
Copyright © Siemens AG 2017 - 2021.
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If more than one degree of danger is present, the warning notice representing the highest degree of danger will
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editions.

CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
Equipment Manual, 07/2021, A5E40882737-AB 3
Preface
Purpose of the documentation
This manual supplements the system manual of the S7-1500 automation system / ET 200MP
distributed I/O system as well as the function manuals. This manual contains a description of
the module-specific information. The system-related functions are described in the system
manual. All system-spanning functions are described in the function manuals.
The information provided in this manual and the system manual enables you to commission
the CPU 1518-4 PN/DP MFP.
Basic knowledge required
To understand this documentation, you need to have general knowledge of automation
engineering. You also need basic knowledge of the following topics:
•Knowledge of the industrial automation system SIMATIC
•Knowledge of working with STEP 7
•Knowledge of working with Linux systems
•Knowledge of programming with C/C++
•Working with the Eclipse development environment
Conventions
•STEP 7: In this documentation, "STEP 7" is used as a synonym for all versions of the
configuration and programming software "STEP 7 (TIA Portal)".
•ODK: Open Development Kit
•SO: Shared Object
•MFP: Multifunctional platform
Please also observe notes marked as follows:
Note
A note contains important information on the product described in the documentation, on
the handling of the product or on the section of the
documentation to which particular
attention should be paid.

Preface
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
4Equipment Manual, 07/2021, A5E40882737-AB
Recycling and disposal
For environmentally friendly recycling and disposal of your old equipment, contact a certified
electronic waste disposal company and dispose of the equipment according to the applicable
regulations in your country.
Security information
Siemens provides products and solutions with industrial security functions that support the
secure operation of plants, systems, machines and networks.
In order to protect plants, systems, machines and networks against cyber threats, it is
necessary to implement – and continuously maintain – a holistic, state-of-the-art industrial
security concept. Siemens’ products and solutions constitute one element of such a concept.
Customers are responsible for preventing unauthorized access to their plants, systems,
machines and networks. Such systems, machines and components should only be connected
to an enterprise network or the internet if and to the extent such a connection is necessary
and only when appropriate security measures (e.g. firewalls and/or network segmentation)
are in place.
For additional information on industrial security measures that may be implemented, please
visit (https://www.siemens.com/industrialsecurity).
Siemens' products and solutions undergo continuous development to make them more
secure. Siemens strongly recommends that product updates are applied as soon as they are
available and that the latest product versions are used. Use of product versions that are no
longer supported, and failure to apply the latest updates may increase customers' exposure to
cyber threats.
To stay informed about product updates, subscribe to the Siemens Industrial Security RSS
Feed visit (https://www.siemens.com/industrialsecurity).

Preface
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
Equipment Manual, 07/2021, A5E40882737-AB 5
Siemens Industry Online Support
You can find current information on the following topics quickly and easily here:
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FAQs, certificates, downloads, and manuals.
•Application examples
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•mySupport
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This information is provided by the Siemens Industry Online Support in the Internet
(https://support.industry.siemens.com).
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The Industry Mall is the catalog and order system of Siemens AG for automation and drive
solutions on the basis of Totally Integrated Automation (TIA) and Totally Integrated Power
(TIP).
You can find catalogs for all automation and drive products on the Internet
(https://mall.industry.siemens.com).

CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
6Equipment Manual, 07/2021, A5E40882737-AB
Table of contents
Preface................................................................................................................................................... 3
1 Documentation guide............................................................................................................................ 7
2 Product overview................................................................................................................................... 9
2.1 New functions ..................................................................................................................... 9
2.2 Applications of the S7-1500 CPUs ...................................................................................... 14
2.3 Hardware properties .......................................................................................................... 25
2.4 Firmware functions............................................................................................................ 27
2.4.1 Quick start instructions for commissioning C/C++ Runtime ................................................. 31
2.4.2 Supplied libraries for C/C++ Runtime .................................................................................. 37
2.5 Operating and display elements......................................................................................... 37
2.5.1 Front view of the CPU with the front panel......................................................................... 37
2.5.2 Front view of the CPU without front panel.......................................................................... 40
2.5.3 Rear view of the CPU.......................................................................................................... 41
2.6 Mode selector switch......................................................................................................... 41
3 Connecting up ..................................................................................................................................... 42
4 Interrupts, error messages, diagnostics and system alarms ............................................................... 47
4.1 Status and error display of the CPU..................................................................................... 47
5 Technical specifications....................................................................................................................... 50
A Dimensional drawing .......................................................................................................................... 65

CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
Equipment Manual, 07/2021, A5E40882737-AB 7
Documentation guide
1
The documentation for the SIMATIC S7-1500 automation system and the SIMATIC ET 200MP
distributed I/O system is arranged into three areas.
This arrangement enables you to access the specific content you require.
Basic information
The System Manual and Getting Started describe in detail the configuration, installation,
wiring and commissioning of the SIMATIC S7-1500 and ET 200MP systems. The STEP 7 online
help supports you in the configuration and programming.
Device information
Product manuals contain a compact description of the module-specific information, such as
properties, wiring diagrams, characteristics and technical specifications.
General information
The function manuals contain detailed descriptions on general topics regarding the SIMATIC
S7-1500 and ET 200MP systems, e.g. diagnostics, communication, motion control, Web
server, OPC UA.
You can download the documentation free of charge from the Internet
(https://support.industry.siemens.com/cs/ww/en/view/109742691).
Changes and supplements to the manuals are documented in a Product Information.
You can download the product information free of charge from the Internet
(https://support.industry.siemens.com/cs/us/en/view/68052815).

Documentation guide
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
8Equipment Manual, 07/2021, A5E40882737-AB
Manual Collection S7-1500/ET 200MP
The Manual Collection contains the complete documentation on the SIMATIC S7-1500
automation system and the ET 200MP distributed I/O system gathered together in one file.
You can find the Manual Collection on the Internet
(https://support.industry.siemens.com/cs/ww/en/view/86140384).
SIMATIC S7-1500 comparison list for programming languages
The comparison list contains an overview of which instructions and functions you can use for
which controller families.
You can find the comparison list on the Internet
(https://support.industry.siemens.com/cs/ww/en/view/86630375).
"mySupport"
With "mySupport", your personal workspace, you make the best out of your Industry Online
Support.
In "mySupport", you can save filters, favorites and tags, request CAx data and compile your
personal library in the Documentation area. In addition, your data is already filled out in
support requests and you can get an overview of your current requests at any time.
You must register once to use the full functionality of "mySupport".
You can find "mySupport" on the Internet (https://support.industry.siemens.com/My/ww/en).
Application examples
The application examples support you with various tools and examples for solving your
automation tasks. Solutions are shown in interplay with multiple components in the system -
separated from the focus on individual products.
You will find the application examples on the Internet
(https://support.industry.siemens.com/cs/ww/en/ps/ae).

CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
Equipment Manual, 07/2021, A5E40882737-AB 9
Product overview
2
2.1 New functions
New functions of the CPU in firmware version V2.9
New functions Applications Customer benefits Where can I find infor-
mation?
Communication of the CPU
Secure PG/HMI
communication
With STEP 7 and WinCC as of Ver-
sion V17, SIMATIC S7-1500 CPUs
and ET 200 CPUs from firmware
version 2.9 support innovated and
standardized secure PG/PC and HMI
communication – referred to as
Secure PG/HMI communication for
short.
Secure and standardized creation or
assignment of PLC communication
certificates
Communication function
manual
(https://support.industry.sie
mens.com/cs/ww/en/view/5
9192925)
Protection of
confidential con-
figuration data
You have the option of assigning a
password for protecting confiden-
tial configuration data of the re-
spective CPU. This refers to data
such as private keys that are re-
quired for the proper functioning
of certificate-based protocols.
Additional password protection of
confidential configuration data
OPC UA: Alarms
& Conditions OPC UA clients from any manufac- turer can subscribe to messages of
the CPU via OPC UA Alarms & Con-
ditions.
Messages created once via OPC UA
are available as events and alarms
without any further measures having
to be taken. The messages can be
displayed by any display device with
corresponding OPC UA client func-
tionality.
OPC UA: Certifi-
cate manage-
ment via Global
Discovery Server
(GDS)
Via GDS push management func-
tions:
•Automatic update of OPC UA
certificates of an S7-1500 CPU
•Transfer of updated certificates
and lists in RUN operating state
of the CPU
The automation of the certificate
management eliminates any manual
work required for reconfiguring the
CPU, for example, after a certificate
has expired, and a new download to
the CPU.

Product overview
2.1 New functions
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
10 Equipment Manual, 07/2021, A5E40882737-AB
New functions Applications Customer benefits Where can I find infor-
mation?
DHCP (Dynamic
Host Configura-
tion Protocol)
The CPU can use the DHCP com-
munication protocol to assign the
network configuration via a DHCP
server. The CPU uses a client ID for
identification on the DHCP server.
The following parameters can be
obtained:
•IP Suite
•DNS server
•NTP server
The CPU can also send its host
name to the DHCP server.
With DHCP, you can integrate the
CPU into an existing IT network
without having to make additional
changes to the PROFINET interface.
MRP interconnec-
tion in PROFINET
networks
The MRP interconnection proce-
dure is an extension of MRP.
MRP interconnection enables the
redundant coupling of two or more
rings with MRP in PROFINET net-
works.
The limit of maximum 50 devices in a
ring does not apply when setting up
redundant network topologies.
Monitoring larger topologies with
ring redundancy
PROFINET function manual
(https://support.industry.sie
mens.com/cs/ww/en/view/4
9948856)
Web server of the CPU
Web applications
that can be load-
ed by the user
Additional methods to easily man-
age web applications via Web API
All available Web API methods can
be used within the web application
Web applications are also available in
STOP mode of the CPU
Reduced development times of web
server user pages
Web server function manu-
al
(https://support.industry.sie
mens.com/cs/ww/en/view/5
9193560)
New Web API
methods
Reading and changing the CPU
operating state via Web API
Ticket methods for transferring
large amounts of data outside of
the JSON RPC protocol
Additional applications for the web
server
Diagnostic infor-
mation on mo-
tion control
Diagnostic information is available
for all technology objects
Improved display and grouping of
the tags
More comprehensive diagnostic
options are possible via the web
server for motion control applica-
tions.
Optimizations to
the DNS (Domain
Name System)
functionality with
OPC UA/Open
User Communi-
cation and on the
web server
Optimizations to the DNS (Domain
Name System) functionality with
OPC UA/Open User Communication
and on the web server
The NTP client of the CPU can ad-
dress its relevant NTP servers via
DNS.
The Web server can be consistently
reached via DNS addressing. DNS is
taken into account during certifi-
cate handling.
A pool of NTP servers can be ad-
dressed.
Communication function
manual
(https://support.industry.sie
mens.com/cs/ww/en/view/5
9192925)
Web server function manu-
al
(https://support.industry.sie
mens.com/cs/ww/en/view/5
9193560)
Technology functions of the CPU
Axis functions
•Backlash compensation
•Linear motor
The repeat accuracy of a movement
is increased by compensation for the
mechanical play of the real axis.
Easier control of highly dynamic
linear motors.
S7-1500T Motion Control
function manuals
(https://support.industry.sie
mens.com/cs/ww/en/view/1
09751049)

Product overview
2.1 New functions
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
Equipment Manual, 07/2021, A5E40882737-AB 11
Extended functions of the CPU in firmware version V2.9
Extended func-
tions
Applications Customer benefits Where can I find infor-
mation?
Work memory
The work memory of the CPU
1518-4 PN/DP MFP was extended
to 116 MB and the work memory
of the CPU 1518F-4 PN/DP MFP to
119 MB.
This expansion allows you to imple-
ment larger and more extensive
applications with the CPUs.
•Section Applications of
the S7-1500 CPUs
(Page 14)
•Section Technical speci-
fications (Page 50)
New functions of the CPU in firmware version V2.8
New functions Applications Customer benefits Where can I find infor-
mation?
SIMATIC Industri-
al OS
The Linux component was updated
to the SIMATIC Industrial OS oper-
ating system with firmware version
V2.8.4 on the CPUs 1518(F)-4
PN/DP MFP (multifunctional plat-
form).
Siemens-administered Linux distribu-
tion: All necessary Linux updates
including security updates are veri-
fied and made available by Siemens.
Section Quick start instruc-
tions for commissioning
C/C++ Runtime (Page 31)
IP forwarding
IP forwarding forwards IP data
through the CPU from one IP sub-
net to another IP subnet.
During IP forwarding, the CPU
automatically creates an IP route
table from the IP configuration in
STEP 7.
•Simplified integration of devices
for remote access, e.g. for diag-
nostics during remote mainte-
nance or firmware update
•Simple access from the control
level to the field level for configu-
ration and parameter assignment
of devices
Example: You can access the Web
server of a drive connected to the
X1 interface of the CPU from a
computer connected to the X2 in-
terface of the CPU.
Communication function
manual
(https://support.industry.sie
mens.com/cs/ww/en/view/5
9192925)
Direct data ex-
change
In the case of direct data exchange,
the CPU cyclically provides user
data from the I/O area to one or
more other CPUs.
The "Direct data exchange" function
enables deterministic, isochronous
I/O communication between multiple
S7-1500 CPUs.
PROFINET function manual
(https://support.industry.sie
mens.com/cs/ww/en/view/4
9948856)

Product overview
2.1 New functions
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
12 Equipment Manual, 07/2021, A5E40882737-AB
New functions Applications Customer benefits Where can I find infor-
mation?
API (Application
Programming
Interface)
The CPU has a web-based API (Ap-
plication Programming Interface)
as an interface for reading and
writing CPU data.
The API supports all conventional
browsers and command line pro-
grams, such as cURL and Wget.
•Established standard mechanisms
for creating Web pages:
Automation Web Programming
commands (AWP commands) are
no longer required for output of
CPU data
•No dependency between custom
web pages and CPU program:
No synchronization between user
program and Web server required
by the SFC 99 instruction
•Lower communication load:
A smaller data packet is trans-
ferred between server and client
(JSON instead of HTML of the
custom Web page generated by
the CPU). This improves the
communication performance.
The CPU needs less runtime to
generate the information and
make it available.
•Secure data traffic:
API exclusively supports the
"HTTPS" transfer protocol
Web server function manu-
al
(https://support.industry.sie
mens.com/cs/ww/en/view/5
9193560)
Cross-device
trace
Coordination of traces on different
devices
•Support of multiple CPUs
•Support of different device
types
Visualization in a shared chart
Support of alternative trigger
sources
•Extensive trigger options for
faster localization of sporadically
occurring errors
•Simple combination of related
traces
Function manual for trace
and logic analyzer function
(https://support.industry.sie
mens.com/cs/ww/en/view/6
4897128)

Product overview
2.1 New functions
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
Equipment Manual, 07/2021, A5E40882737-AB 13
New functions of the CPU in firmware version V2.6
New functions Applications Customer benefits Where can I find infor-
mation?
OPC UA client
In addition to the OPC UA server,
an OPC UA client is integrated in
the CPU.
Using the corresponding OPC UA
communication instructions, you
can:
•Call methods
•Read and write data
You can perform, for example, verti-
cal communication to MES sys-
tems/cloud services or IO controller-
IO controller communication.
Communication
(https://support.industry.sie
mens.com/cs/ww/en/view/5
9192925) function manual
Isochronous
mode for central
I/O
Isochronous mode is also possible
for modules that are inserted next
to the CPU in a centralized configu-
ration.
In this way, you can implement the
following functions, for example:
•Dynamic control tasks
•Measuring input
•Output cam
•Dosing processes, high-speed
analog value acquisition with
oversampling
•Optimized controls through con-
stant, calculable dead times
•Determinism, reliable reproduci-
bility of response times
•Consistent (simultaneous) read-
ing in of input data
•Consistent (simultaneous) output
of output data
•PROFINET
(https://support.industr
y.siemens.com/cs/ww/e
n/view/49948856)
function manual
•Isochronous mode
function manual
(https://support.industr
y.siemens.com/cs/ww/e
n/view/109755401)
•S7-1500T Motion Con-
trol function manuals
(https://support.industr
y.siemens.com/cs/ww/e
n/view/109751049)
Reference
You can find an overview of all new functions, improvements and revisions in the respective
firmware versions on the Internet
(https://support.industry.siemens.com/cs/ww/en/view/109478459).

Product overview
2.2 Applications of the S7-1500 CPUs
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
14 Equipment Manual, 07/2021, A5E40882737-AB
2.2 Applications of the S7-1500 CPUs
Application
SIMATIC S7-1500 is the modular control system for a wide variety of automation applications
in discrete automation.
SIMATIC S7-1500 is the cost-effective and convenient solution for a broad range of tasks and
offers the following advantages:
•Modular, fanless design
•Simple realization of distributed structures
•User-friendly handling
Areas of application of the SIMATIC S7-1500 automation system include, for example:
•Special-purpose machines
•Textile machinery
•Packaging machines
•General mechanical engineering
•Controller engineering
•Machine tool engineering
•Installation engineering
•Electrical industry and crafts
•Automobile engineering
•Water/waste water
•Food & Beverage
Areas of application of the SIMATIC S7-1500R/H redundant system include, for example:
•Tunnels
•Airports (e.g. baggage conveyors)
•Subways
•Shipbuilding
•Wastewater treatment plants
•High-bay warehouses
Areas of application of the SIMATIC S7-1500T automation system for advanced motion
control applications include, for example:
•Packaging machines
•Converting applications
•Assembly automation
•Pick-and-place automation
•Palletizers

Product overview
2.2 Applications of the S7-1500 CPUs
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
Equipment Manual, 07/2021, A5E40882737-AB 15
You can choose between CPUs with various levels of performance and a comprehensive
range of modules with many convenient functions. Fail-safe CPUs enable use in fail-safe
applications. The modular design allows you to use only the modules that you need for your
application. The controller can be retrofitted with additional modules at any time to expand
its range of tasks.
High industrial suitability due to the high resistance to EMC, shock and vibration enable
universal use of the SIMATIC S7-1500, S7-1500R/H and S7-1500T automation systems.
Performance segments of the CPUs
The CPUs can be used for smaller and mid-range applications, as well as for the high-end
range of machine and plant automation.
Table 2- 1 Standard CPUs
CPU Performance segment PROFIBUS
interfaces
PROFINET
IO RT/IRT
interfaces
PROFINET
IO RT
interface
Basic
PROFINET
functional-
ity
Work
memory
Pro-
cessing
time for
bit oper-
ations
CPU 1511-1 PN
Standard CPU for small
to mid-range applica-
tions
--
1
--
--
1.15 MB
60 ns
CPU 1513-1 PN
Standard CPU for mid-
range applications
--
1
--
--
1.8 MB
40 ns
CPU 1515-2 PN Standard CPU for mid-
range to large applica-
tions
-- 1 1 -- 3.5 MB 30 ns
CPU 1516-
3 PN/DP Standard CPU for high- end applications and
communication tasks
1 1 1 -- 6 MB 10 ns
CPU 1517-
3 PN/DP Standard CPU for high- end applications and
communication tasks
1 1 1 -- 10 MB 2 ns
CPU 1518-
4 PN/DP Standard CPU for high- performance applica-
tions, demanding com-
munication tasks and
very short reaction
times
1 1 1 1 66 MB 1 ns
CPU 1518-
4 PN/DP MFP
Standard CPU for high-
performance applica-
tions, demanding com-
munication tasks, very
short reaction times and
C/C++ blocks for the
user program
1
1
1
1
116* MB
1 ns
* 50 MB of the integrated work memory is reserved for the function library of CPU runtime

Product overview
2.2 Applications of the S7-1500 CPUs
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
16 Equipment Manual, 07/2021, A5E40882737-AB
Table 2- 2 Redundant CPUs
CPU Performance segment PROFIBUS
interfaces
PROFINET
IO RT/IRT
interfaces
PROFINET
IO RT
interface
Basic
PROFINET
functional-
ity
Work
memory
Pro-
cessing
time for
bit oper-
ations
CPU 1513R-1 PN
Redundant CPU for
smaller to mid-range
applications
--
1
--
--
1.8 MB
80 ns
CPU 1515R-2 PN
Redundant CPU for mid-
range to large applica-
tions
--
1
--
1
3.5 MB
60 ns
CPU 1517H-
3 PN
Redundant CPU for
demanding applications
and communication
tasks
--
1
--
1
10 MB
4 ns
Table 2- 3 Compact CPUs
CPU Performance segment PROFIBUS
interfaces
PROFINET
IO RT/IRT
interfaces
PROFINET
IO RT
interface
Basic
PROFINET
functional-
ity
Work
memory
Pro-
cessing
time for
bit oper-
ations
CPU 1511C-1 PN
Compact CPU for small
to mid-range applica-
tions
--
1
--
--
1.175 MB
60 ns
CPU 1512C-1 PN
Compact CPU for mid-
range applications
--
1
--
--
1.25 MB
48 ns
Table 2- 4 Fail-safe CPUs
CPU Performance segment PROFIBUS
interfaces
PROFINET
IO RT/IRT
interfaces
PROFINET
IO RT
interface
Basic
PROFINET
functional-
ity
Work
memory
Pro-
cessing
time for
bit oper-
ations
CPU 1511F-1 PN
Fail-safe CPU for smaller
to medium-sized appli-
cations
--
1
--
--
1.225 MB
60 ns
CPU 1511TF-
1 PN
Fail-safe technology
CPU for small to mid-
range applications
--
1
--
--
1.225 MB
60 ns
CPU 1513F-1 PN
Fail-safe CPU for medi-
um-sized applications
--
1
--
--
1.95 MB
40 ns
CPU 1515F-2 PN
Fail-safe CPU for medi-
um-sized to large appli-
cations
--
1
1
--
3.75 MB
30 ns

Product overview
2.2 Applications of the S7-1500 CPUs
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
Equipment Manual, 07/2021, A5E40882737-AB 17
CPU Performance segment PROFIBUS
interfaces
PROFINET
IO RT/IRT
interfaces
PROFINET
IO RT
interface
Basic
PROFINET
functional-
ity
Work
memory
Pro-
cessing
time for
bit oper-
ations
CPU 1515TF-
2 PN
Fail-safe technology
CPU for complex appli-
cations and communi-
cation tasks
--
1
1
--
3.75 MB
30 ns
CPU 1516F-
3 PN/DP
Fail-safe CPU for de-
manding applications
and communications
tasks
1
1
1
--
6.5 MB
10 ns
CPU 1516TF-
3 PN/DP
Fail-safe technology
CPU for complex appli-
cations and communi-
cation tasks
1
1
1
--
6.5 MB
10 ns
CPU 1517F-
3 PN/DP
Fail-safe CPU for de-
manding applications
and communications
tasks
1
1
1
--
11 MB
2 ns
CPU 1517TF-3
PN/DP Fail-safe technology CPU for complex appli-
cations and communi-
cation tasks
1 1 1 -- 11 MB 2 ns
CPU 1518F-
4 PN/DP
Fail-safe CPU for high-
performance applica-
tions, demanding com-
munication tasks and
very short reaction
times
1
1
1
1
69 MB
1 ns
CPU 1518F-
4 PN/DP MFP
Fail-safe CPU for high-
performance applica-
tions, demanding com-
munication tasks, very
short reaction times and
C/C++ blocks for the
user program
1
1
1
1
119* MB
1 ns
CPU 1518TF-
4 PN/DP
Technology CPU for
high-performance mo-
tion control applications
with large quantities,
demanding communi-
cation tasks and very
short reaction times
1
1
1
1
69 MB
1 ns
CPU 1518HF-
4 PN
Fail-safe redundant CPU
for high-performance
applications and de-
manding communica-
tions tasks
--
1
--
2
69 MB
4 ns
* 50 MB of the integrated work memory is reserved for the function library of CPU runtime

Product overview
2.2 Applications of the S7-1500 CPUs
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
18 Equipment Manual, 07/2021, A5E40882737-AB
Table 2- 5 Technology CPUs
CPU Performance segment PROFIBUS
interfaces
PROFINET
IO RT/IRT
interfaces
PROFINET
IO RT
interface
Basic
PROFINET
functional-
ity
Work
memory
Pro-
cessing
time for
bit oper-
ations
CPU 1511T-1 PN
Technology CPU for
small to mid-range
applications
--
1
--
--
1.225 MB
60 ns
CPU 1515T-2 PN
Technology CPU for
mid-range to large ap-
plications
--
1
1
--
3.75 MB
30 ns
CPU 1516T-
3 PN/DP
Technology CPU for
high-end applications
and communication
tasks
1
1
1
--
6.5 MB
10 ns
CPU 1517T-
3 PN/DP
Technology CPU for
high-end applications
and communication
tasks
1
1
1
--
11 MB
2 ns
CPU 1518T-
4 PN/DP
Technology CPU for
high-performance mo-
tion control applications
with large quantities,
demanding communi-
cation tasks and very
short reaction times
1
1
1
1
69 MB
1 ns
CPU 1511TF-
1 PN
CPU 1515TF-
2 PN
CPU 1516TF-
3 PN/DP
CPU 1517TF-
3 PN/DP
CPU 1518TF-
4 PN/DP
These CPUs are described in the fail-safe CPUs

Product overview
2.2 Applications of the S7-1500 CPUs
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
Equipment Manual, 07/2021, A5E40882737-AB 19
Power segment of the CPU 1518-4 PN/DP MFP
The CPU 1518-4 PN/DP MFP can be used for the high-end area of machine and plant
automation.
The CPU 1518-4 PN/DP MFP offers you the following options:
•Executing STEP 7 blocks of the "standard" user program
•Executing applications that were programmed in C/C++ with the Open Development Kit
ODK
–Run C/C++ code synchronously in the CPU cycle via the CPU function library
–Run C/C++ applications as separate applications parallel to CPU runtime