PROFINET

System Validation

Quality Criteria for Planning

and Technical Acceptance Testing

Updated Planning

and

Commissioning

Guidelines for

PROFINET

Xaver Schmidt

Current situation

PROFINET is an internationally standardized bus protocol.

The specified behavior of the devices is documented and is tested and documented in device tests(certification testing). Device Certification

The planning and structuring of PROFINET networks is

documented in the PROFINET Design Guideline.

Nevertheless, the question arises with users as to how the

configuration and quality of the network can be evaluated

during the acceptance testing

System Validation

The WG CB/PG3 Installation Guide PB & PN therefore

revised and expanded the PROFINET Design and

Commissioning Guidelines in the past year.

3

Xaver Schmidt / PROFINET System Validation

New Guidelines Design / Commissioning

PROFINET Design Guideline Version 1.14, December 2014 Order No.: 8.062

PROFINET Commissioning Guideline Version 1.36, December 2014 Order No: 8.082

4

Download:

http://www.profibus.com/nc/download/installation-

guide/downloads/profinet-installation-guide/display/

Technical

Background

Folie 6

© AIT Solutions GmbH

cyclic update (I/O cycle)

device run in ‘autonomous‘ mode

devices may have individual I/O cycle

PROFINET Communication

Response time depends on

PLC cycle time Update interval (I/O cycle of PROFINET devices) Communication monitoring (watch dog)

Line depth Switching Technology NRT Netload

Delay

Co

nfi

gura

tio

n

Infr

astr

uct

ure

Response Time

Response time depends on

PLC cycle time Update interval (I/O cycle of PROFINET devices) Communication monitoring (watch dog)

Line depth Switching Technology NRT Netload

Delay

Co

nfi

gura

tio

n

Infr

astr

uct

ure

Response Time

Response time depends on

PLC cycle time Update interval (I/O cycle of PROFINET devices) Communication monitoring (watch dog)

Line depth Switching Technology NRT Netload

Delay

Co

nfi

gura

tio

n

Infr

astr

uct

ure

Response Time

Consequences

Response

Time

Netload

PLC cycle time

I/O cycle time

Watchdog

Line depth

Response Time / Worst Case 12

TD1

TC

TD2

TPN1

TPN2

ΔTPN1

ΔTPN2

Event

ΔTC

Reaction Tc : Cycle Time Controller

ΔTC: Processing Time Controller

TD1, TD2: Cycle Time I/O Devices

TPN1, TPN2: Transmission Time Network

… some Figures

… some figures based on 100 Mbit/s

64 Byte= 512 Bit = approx. 5 microseconds approx. 150 PROFINET packets/ms approx. 0,5% netload per device at an IO cycle of 2 ms 1500 Byte: approx. 125 microseconds approx. 8 IP packets/ms

Netload … some aspects

no uniform load Different in each cable segment Full Duplex Load distribution to/from controller (up-/downstream) …

PLC Devices

Devices PLC

Reference: Klasen, F. / Whitepaper PROFINET Validation

Non-uniform netload 16

Video

camera Video

display

Additions

for planning

Hints for Planning Reliability

The defined recommen-dations and values should assure a secure and reliable operation as well as a good diagnostics of the network.

This does not mean that higher values are not permitted or not necessarily lead to malfunction.

The specified values consider reserves for extensions of the plant over the life time.

E.g., extension of an existing plant by additional functions

18

Time

Utili-

zation

Commissio-

ning

Extension End of

Operation

Uniform

Firmware

versions

Definition of uniform firmware versions

During planning, it is recommended that uniform firmware versions be defined and that this definition be documented.

PROFINET nodes

Network components

This is checked during commissioning.

If there are any different firmware versions, they are to be aligned during commissioning through updating.

20

V1.3

V1.3

V1.1

V1.3

Line

topologies

The long line … 22

Devices with integrated switches facilitate a simple and economical creation of line topologies.

However, very long lines lead to restrictions with respect to:

Availability

Diagnostics

Throughput delay

Two measures should lead to an improvement here:

Definition of a primary infrastructure

Specification of a maximum line depth

Primary

infrastructure

consisting of

switches.

Primary infrastructure for lines 23

Lines branching

from this.

Tree structure

building on this

Line depth 24

1 2 3 4

5

6

7 8

9

→ Line depth: 9 (cut-through switches)

Maximum Line Depths 25

Store and Forward Switches

Maximum Line Depths with Update Time of

1 ms 2 ms 4 ms 8 ms

7 14 28 58

Cut through Switches

Maximum Line Depths with Update Time of

1 ms 2 ms 4 ms 8 ms

64 100 100 100

Cycle times

and Timeouts

Cycles at Data Transfer 27

Task PROFINET Task Task PROFINET

Processing Chain, Shortest Reaction Time 28

ΔTC

TD1

TC

TD2

TPN1

TPN2

ΔTPN1

ΔTPN2

Event

Reaction Tc : Cycle Time Controller

ΔTC: Processing Time Controller

TD1, TD2: Cycle Time I/O Devices

TPN1, TPN2: Transmission Time Network

Processing Chain, Longest Reaction Time 29

TD1

TC

TD2

TPN1

TPN2

ΔTPN1

ΔTPN2

Event

ΔTC

Reaction Tc : Cycle Time Controller

ΔTC: Processing Time Controller

TD1, TD2: Cycle Time I/O Devices

TPN1, TPN2: Transmission Time Network Prof. Dr. Frithjof Klasen / PROFINET System Validation

Recommendation for Cycle Time

Recommendation:

The shorter the update time is the more bandwith is consumed by the cyclic real time communication

Longer update times cause longer reaction times

Therefore, for each PROFINET Device you should choose update time as short as necessary and as long as possible

The following slide gives you a hint on how the I/O Cycle Time influences the Netload

30

Cyclic PROFINET Netload 31

0

10

20

30

40

50

60

70

80

90

100

0 20 40 60 80 100 120 140 160 180 200

Ne

tzla

st

in %

Anzahl Netzwerkteilnehmer

2 ms Aktualisierungszeit 4 ms Aktualisierungszeit 8 ms Aktualisierungszeit

PROFINET Paket Size of 108 Byte

(60 Byte User Data)

Error Counter (1) 32

0

0

1

2

0

0

1

2

t t

Co

un

ter

Sta

tus

Co

un

ter

Sta

tus

EMI

EMI

EMI

EMI

EMI

EMI

Watchdog / Error counter (3)

A higher threshold increases the error tolerance in the event of a malfunction, but extends the time until an error is detected.

It is recommended that the default setting of 3 be used. If a value other than this default is used, a check must be performed to determine whether the reaction time is sufficiently short in the event of a malfunction.

33

Netload

Netload, Multi Controller 36

1%

1% 1%

3%

1% 1%

3%

1%

2%

1% 1% 1% 1%

1%

1%

Cyclic Real Time Load 37

Update time Generated cyclic real time netload per

PROFINET Device

1 ms 0,86 %

2 ms 0,43 %

4 ms 0,22 %

8 ms 0,11 %

Generated cyclic real time netload (typ. PROFINET Packet Size

60 Byte PROFINET User data, 100 Mbit/s)

Prof. Dr. Frithjof Klasen / PROFINET System Validation

Cyclic Real Time Communication 38

Netload Recommendation

< 20%: No action neccessary

20…50%: It is recommended to check the designed netload

> 50%: There is a necessity to take measures to reduce the netload

Recommended threshold values for

netload of cyclic real time communication

Standard Ethernet Participant (1) 39

Video

camera Video

display

Standard Ethernet Participant (2) 40

Video

camera Video

display

41

User Interface Netload Calculation Tool

Minimaler Sendetakt ms

Gerätegruppe Gruppe 1 Gruppe 2 Gruppe 3 Gruppe 4 Gruppe 5 Gruppe 6

Anzahl Geräte 1 0 0

Nutzung von IRT

Anzahl der ModuleInput 40 10

Output 30 10

Nettodaten je GerätInput Daten 30 20 Bytes 100 Bytes

Output Daten 40 20 Bytes 100 Bytes

Sendetakt je GerätegruppeInput 4 1 ms 1 ms

Output 8 1 ms 1 ms

TaktinformationenSendClock Factor 32 32 32 32 32 32

Reduction Ratio Output 4 1 0 1 0 0

Reduction Ratio Input 8 1 0 1 0 0

Netzlast je Gerät

Resultirende PROFINET-Netzlast Input 0,296 0,704 MBit/s Input 1,200 MBit/s

Output 0,158 0,704 MBit/s Output 1,200 MBit/s

Netzlast je GerätegruppeResultirende PROFINET-Netzlast Input 0,296 0,000 MBit/s Input 0,000 MBit/s

Output 0,158 0,000 MBit/s Output 0,000 MBit/s

A

u

s

g

a

b

e

f

e

l

d

e

r MBit/s Input MBit/s

E

i

n

g

a

b

e

f

e

l

d

e

r

1

Gemeinsame Netzlast auf einer Leitung

0,296Output 0,158

Netzlast-Berechnung

1

Remote IO Antriebe

Download:

http://www.profibus.com/nc/

download/installation-

guide/downloads/profinet-

installation-

guide/download/18580/

Additions to

commissioning

Network parameters and anomalies

DCP Multicast

ARP Broadcast

MRP Multicast

CRC Errors

discarded packets

43

Check list 44

New Guidelines Design / Commissioning

PROFINET Design Guideline Version 1.14, December 2014 Order No.: 8.062

PROFINET Commissioning Guideline Version 1.36, December 2014 Order No: 8.082

45

Download:

http://www.profibus.com/nc/download/installation-

guide/downloads/profinet-installation-guide/display/

Thank You!

Xaver Schmidt