21669756_Zeitschaltuhr_einfach_DOKU_v21_e.pdf

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Applications & ToolsAnswers for industry.

Cover

Time Switch Based on anS7-300/400 CPU with optionalRadio Clock Connection

SIMATIC S7-300/400

Application Description March 2011


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2Time Switches

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011Allrightsreserved

Industry Automation and Drive Technologies Service & Support Portal

This document is taken from the Service Portal of Siemens AG, IndustryAutomation and Drive Technologies. The following link takes you directly to thedownload page of this document.

http://support.automation.siemens.com/WW/view/en/21669756

If you have any questions concerning this document please e-mail us to thefollowing address:

[email protected]
http://support.automation.siemens.com/WW/view/en/21669756mailto:[email protected]:[email protected]://support.automation.siemens.com/WW/view/en/21669756


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Time SwitchesV2.1, ID Number: 21669756 3

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s

SIMATIC

Time Switches

SIMATIC S7-300/400

Automation Problem 1

Automation Solution 2

Functional Mechanismsof this Application 3

Installation 4

Description of theTime Switching Functions

5

Operation of the

Application 6

Further Notes, Tips andTricks, etc. 7

References 8

History 9


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Warranty and Liability

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Warranty and LiabilityNote The application examples are not binding and do not claim to be complete

regarding the circuits shown, equipping and any eventuality. The applicationexamples do not represent customer-specific solutions. They are only intended

to provide support for typical applications. You are responsible for ensuring thatthe described products are correctly used. These application examples do notrelieve you of the responsibility of safely and professionally using, installing,operating and servicing equipment. When using these application examples, yourecognize that Siemens cannot be made liable for any damage/claims beyondthe liability clause described. We reserve the right to make changes to theseapplication examples at any time without prior notice. If there are any deviationsbetween the recommendations provided in these application examples and otherSiemens publications e.g. Catalogs then the contents of the other documentshave priority.

We do not accept any liability for the information contained in this document.

Any claims against us based on whatever legal reason resulting from the use ofthe examples, information, programs, engineering and performance data etc.described in this application example shall be excluded. Such an exclusion shallnot apply in the case of mandatory liability, e.g. under the German Product LiabilityAct (Produkthaftungsgesetz), in case of intent, gross negligence, or injury of life,body or health, guarantee for the quality of a product, fraudulent concealment of adeficiency or breach of a condition which goes to the root of the contract(wesentliche Vertragspflichten). However, claims arising from a breach of acondition which goes to the root of the contract shall be limited to the foreseeabledamage which is intrinsic to the contract, unless caused by intent or grossnegligence or based on mandatory liability for injury of life, body or health. Theabove provisions do not imply a change in the burden of proof to your detriment.

It is not permissible to transfer or copy these application examples or excerpts ofthem without first having prior authorization from Siemens Industry Sector inwriting.


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Table of Contents


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Table of ContentsWarranty and Liability ................................................................................................. 4

1 Automation Problem ......................................................................................... 7

1.1 Overview .............................................................................................. 71.2 Requirements ....................................................................................... 7

2 Automation Solution ......................................................................................... 9

2.1 Overview of the overall solution ........................................................... 92.2 Description of the core functionality ..................................................... 92.3 Hardware and software components used......................................... 10

3 Functional Mechanisms of this Application ................................................. 11

3.1 Absolute time switching functions ...................................................... 113.1.1 Day time switch .................................................................................. 113.1.2 Week time switch ............................................................................... 123.1.3 Month time switch............................................................................... 12

3.1.4 Year time switch................................................................................. 123.2 Relative time switching function......................................................... 133.2.1 Relative time switch............................................................................ 133.3 Additional functions ............................................................................ 133.3.1 Summer-/wintertime changeover ....................................................... 133.3.2 Identification of holidays/special days................................................ 13

4 Installation........................................................................................................ 14

4.1 Hardware installation.......................................................................... 14

5 Description of the Time Switching Functions .............................................. 16

5.1 Absolute time switching functions ...................................................... 175.1.1 Day time switch .................................................................................. 195.1.2 Week time switch ............................................................................... 205.1.3 Month time switch............................................................................... 215.1.4 Year time switch................................................................................. 225.2 Relative time switch............................................................................ 235.3 Additional functions ............................................................................ 255.3.1 Program-controlled summer-/wintertime changeover........................ 255.3.2 Radio-controlled summer-/wintertime changeover ............................ 265.3.3 Identification of holidays..................................................................... 27

6 Operation of the Application .......................................................................... 28

6.1 Absolute time switching functions ...................................................... 286.2 Relative time switching function......................................................... 296.3 Input of special days........................................................................... 30

7 Further Notes, Tips and Tricks, etc. .............................................................. 31

7.1 How can I include several switch-on/switch-off times in one block?.. 317.2 What do I have to do if I need more holidays or special days? ......... 317.3 How can I integrate a SICLOCK radio clock into the project? ........... 327.3.1 Introduction......................................................................................... 327.3.2 Functionality ....................................................................................... 327.3.3 Performance data............................................................................... 327.3.4 Hardware components....................................................................... 337.3.5 Hardware connection ......................................................................... 337.3.6 Software interface and block parameterization.................................. 35

8 References ....................................................................................................... 36

8.1 References ......................................................................................... 36


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8.2 Internet links ....................................................................................... 36

9 History............................................................................................................... 36


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1 Automation Problem


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1.1 Overview

Many fields of automation require accurate timing of processes. Even in domesticelectrical installation practice, individual systems must operate, for example,depending on the time of day or the day of the week. One possibility to solve thisproblem is to use electrical or mechanical time switches. The figure below showsexamples of electrical time switches:

Figure 1-1: Examples of time switches

All of the examples are hardware clocks that can be used to solve the time

switching problem in domestic electrical installation practice. Operation is keptsimple so that this clock can be easily used by ordinary persons.

Accurate time switching of processes is also necessary in a large number ofindustrial applications in the field of automation.

1.2 Requirements

To be able to create the time characteristic of such or similar processes, theS7 CPU requires a block that, depending on the absolute time, sets an output orensures that a parameterized time interval elapses when a specific event occurs.

The absolute start and end times for these processes must be configurable on a

relevant block and then be available in the S7 CPU. In addition, it is to be possibleto parameterize a specific time interval that will elapse depending on a start event(relative time).


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Requirements for the automation problem

In the S7 CPU, the automation problem requirements for the application are asfollows:

The following blocks exist:

Day, week, month, year time switch

Relative time switch

Summer-/wintertime changeover

Identification of holidays

Radio clock connection

Start and end time can be parameterized for each time switch (day, week,month, year time switch and relative time switch).

The time switches must be easily resettable.


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2 Automation Solution


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2.1 Overview of the overall solution

Figure 2-1: Overall solution

2.2 Description of the core functionality

The application includes function blocks for absolute and relative time switchingfunctions (clocks). Each clock has only one setting option (corresponds to onecam), i.e. one switch-on time and one switch-off time can be entered on a block.This property has several advantages:

The design of the function blocks is very fine-grained. This allows optimumutilization of the memory requirement in the S7 CPU.

The blocks can be used flexibly.

The blocks can be easily parameterized.

Furthermore, the application includes additional functions such as summer-/wintertime changeover and identification of holidays.

By default, the additional Summer-/wintertime changeover function is executed bya function block. As an option, this changeover can also be controlled using a radioclock. In this case, a digital input module (here: SM321) must be used since twodigital inputs are necessary to receive the data sent from the radio clock module.

DCF77


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2.3 Hardware and software components used

The application was created with the following components:

Hardware components

Table 2-1: Hardware used

Component Qty. MLFB/order number Note

PS307 2A 1 6ES7 307-1BA00-0AA0 Or similarpower supply

CPU 315-2 DP 1 6ES7-315-2AG10-0AB0 Or other CPU

Optional hardware components (only necessary when using a radio clock):

Table 2-2: Optional hardware


SM 321 1 6ES7 321-7BH00-0AB0 Or other digitalinput module

SIPLUS DCF77radio receiver

1 6AG1057-1AA03-0AA0 Or SICLOCK

Software components

Table 2-3: Standard software


STEP7 V5.4+SP5 1 6ES7810-4CC08-0YA5

Sample files and projects

The following list contains all files and projects that are used in this example.

Table 2-4: Files of the application

Component Note

21669756_Zeitschaltuhr_einfach_CODE_V2.1.zip This zip file contains the STEP 7project.

21669756_Zeitschaltuhr_einfach_DOKU_V2.1.pdf This document.


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3 Functional Mechanisms of this Application


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3 Functional Mechanisms of this ApplicationThe functions included in this application can be divided into the following groups.

Figure 3-1: Function chart

3.1 Absolute time switching functions

3.1.1 Day time switch

This block can cover a time interval within 24 hours, for example 8:00 a.m. to 12:00a.m. These switching times are repeated on a daily basis.

Figure 3-2: Day time switch

12:00 a.m 11:59:59 p.m

8:00 a.m. 12:00 a.m.


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3.1.2 Week time switch

This block can cover a time interval within 7 days, for example each Tuesday from

8:00 p.m. to Friday 6:00 a.m. These switching times are repeated on a weeklybasis.

Note It is also possible to repeat one switching time on a daily basis from Monday toFriday.

Figure 3-3: Week time switch

Tue, 8:00 p.m.

Sun 12:00 Sat 11:59:59 p.m.

Fri, 6:00 a.m.

3.1.3 Month time switch

This block can cover a time interval within 31 days, for example each month from12:00 a.m. on the 3

rdto 9:00 p.m. on the 7

th.

Figure 3-4: Month time switch

1st

0:00 a.m.

31st

11:59:59 p.m.

3r, 12:00 a.m. 7

t, 9:00 p.m.

3.1.4 Year time switch

This block can cover a time interval within 365 days, for example from April 13,8:00 a.m. to September 28, 12:00 noon.

Figure 3-5: Year time switch

1st

Jan.

0:00 a.m.

31st Dec.

11:59:59 p.m.

13t

April, 8:00 28t

Sept, 12:00


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3.2 Relative time switching function3.2.1 Relative time switch

The clock is activated by a start signal and remains active until the parameterizedtime interval has elapsed.

Figure 3-6: Relative time switch

Start signal

Parameterized time

(e.g.: 3 hours)

3.3 Additional functions

3.3.1 Summer-/wintertime changeover

The absolute system time in the S7 CPU is changed by plus or minus 1 hour,

depending on whether the changeover is performed from wintertime tosummertime or from summertime to wintertime.

For the summer-/wintertime changeover, two options are available:

1. Radio-controlled changeoverThe system time is adjusted after the radio clock connected to the system hasprovided the changeover signal.

2. Program-controlled changeover:A supplied function block adjusts the system time at the officially defined times.

3.3.2 Identification of holidays/special days

In a data block, the data for holidays and special days is stored in day/month/yearformat. The block checks whether a day in this data block matches the current dateand then sets an output to 1. Otherwise, the output is 0.

When wiring this output to an EnableClock input of a time switch, you can achievethat, for example, the day time switch is not switched on on holidays.


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4 Installation

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4 Installation

4.1 Hardware installation

For the hardware components, please refer to chapter2.3Hardware and softwarecomponents used.

Figure 4-1: Hardware of the application

Note The installation guidelines for SIMATIC modules must always be observed.

Hardware installation: Radio clock

Using a 4-wire shielded cable, the SIPLUS DCF77 radio clock module is wired tothe power supply / SM 321 as follows:

Table 4-1: Hardware installation: Radio clock

PS SM 321 SIPLUS DCF77

E 0.0 Sec

E 0.1 DCF Data

L+ 24Vdc

M Ground

You can also connect the radio clock to digital inputs that differ from the onesdescribed here. In this case, you only have to adjust the interconnection of theSekTakt and Data parameters in OB1 when calling FB77 DCF77_FB.

Functions of the LEDS on the SIPLUS DCF77 radio clock module:

Green LED: 24Vdc: Power supply is connected

Center red LED: DCF data: Data transfer to the automation system

Outer red LED: sec: Second settings from atomic clock


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Note When selecting the place of installation of the SIPLUS DCF77 radio clockmodule, it should be ensured that the radio clock signal is not shielded bybuilding faades made of metal or similar material. The actual module must beshielded from interference frequencies and should not be attached directly on a

metal surface.

At the place of installation, radio reception can be tested by applying the supplyvoltage to the SIPLUS DCF77 radio clock module. If there is radio reception, theouter red LED must flash every second. If this is not the case or if the LEDsputters after a longer period of operation, a more suitable place of installationshould be selected. Depending on the reception conditions, setting the clocknormally lasts approximately 3-4 minutes; however, it may take longer atunfavorable places of installation.


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5 Description of the Time Switching Functions

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5 Description of the Time SwitchingFunctions

The figure below shows the program structure and the used blocks.

Figure 5-1: Program structure

OB1

call summer_winterFB103 FB103

prfe, ob Sommer-/Winterzeit-umschaltungstattgefunden hat

DB103

InstanzDB zu FB103

callday FB120 FB120

prfe, ob aktuelle Zeit impara-

metriertenZeitraum liegt

DB120

InstanzDB zu FB120

call weekFB121 FB121

prfe, ob aktuelle Zeit impara-metriertenZeitraum liegt

DB121

InstanzDB zu FB121

call monthFB122 FB122

prfe, ob aktuelle Zeit impara-metriertenZeitraum liegt

DB122

InstanzDB zu FB122

call yearFB123 FB123



DB123

InstanzDB zu FB123

call relativ FB124 FB124



DB124

InstanzDB zu FB124

callcheck_holidaysFC100 FC100

prfe, ob aktuelles Datum ein

Feiertag oder Sondertag ist

DB100

DB mit Feier-und Sondertagen Additionalfunctions

Absolute

tim

eswitchingfunctions

Relative

timeswitchingfunction

(Kapitel 4.3.3.1)

(Kapitel 4.3.3.2)

(Kapitel 4.3.1.1)

(Kapitel 4.3.1.2)

(Kapitel 4.3.1.3)

(Kapitel 4.3.1.4)

(Kapitel 4.3.2)

OB1

call summer_winterFB103 FB103

check whether summer/wintertime changeover occurred

DB103

InstancDBto FB103

calltimer_day FB120 FB120

check whether current time is

within parameterized range

DB120

Instance DBto FB120

call timer_week FB121 FB121

check whether current time iswithin parameterized range

DB121

InstancDB to FB121

call timer_month FB122 FB122

check whether current time iswithin parameterized range

DB122

InstancDB to FB122

call timer_year FB123 FB123



DB123

InstancDB to FB123

call timer_relativ FB124 FB124



DB124

InstancDB to FB124

callspecial_daysFC100 FC100

check whether current date is

holiday or special day

DB100

DB with holiday/special days


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The absolute time switching functions include

day time switch

week time switch

month time switch

year time switch.

Each of the blocks has the following inputs:

EnableClock of the BOOL type

Value = 1: Clock is enabled

Value = 0: Clock is not enabled

Time_To_Check of the UDT type

The parameter contains the time interval during which the clock is to beactive, including absolute start and end time. The parameter is specific foreach time switch.

Note The Time_To_Check parameter of the week time switch is an in/out parameter.

Reset of the BOOL type

Value = 1: Clock is reset

Value = 0: Clock is in normal mode

Each of the blocks has the following outputs:

Q = clock active of the BOOL type

The parameter indicates whether the clock is active.

Value = 1: Clock is active

Value = 0: Clock is not active

Error of the INT type Value = 0: No error has occurred

Value 0: An error has occurred

Possible errors:

Return values of called SFCs in the block (e.g., SFC1 Read_Clk)

8000h in the event of a limit violation on the input parameters

8001h if start time equals end time


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Note The EN input parameter and the ENO output parameter are parameters thatare included by default in the S7 blocks. For more information, please refer to theSTEP 7 documentation and the respective online help.

The EnableClock, Time_To_Check and Reset input signals and the Q outputbehave towards one another as shown in the following pulse timing diagram:

ime range

t is a programmed time range (time switch active)

The pulse timing diagram applies to all absolute function blocks, which aredescribed in detail in the following sections.


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5.1.1 Day time switch

FB timer_day checks whether the current system time in the S7 CPU is within the

parameterized time interval on the input parameters of the block. If this is the case,the output will be set to 1. Otherwise, the output is 0.

The block for the timer_day FB120 day time switch is parameterized as shown inthe figure below. Data block DB120 is used as an instance data block:

Figure 5-2: timer_day

The Time_To_Check parameter is a structure of the UDT_timer_day (UDT1)type. It includes:

Start hour, start minute, start second, combined as starttime and with astructure of the times (UDT6) type

End hour, end minute, end second, combined as endtime and with a structure

of the times (UDT6) type


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5.1.2 Week time switch

FB timer_week checks whether the current system time and the current weekday

in the S7 CPU are within the parameterized time interval on the input parameters ofthe block. If this is the case, the output will be set to 1. Otherwise, the output is0.

The block for the timer_week FB121 week time switch is parameterized as shownin the figure below. Data block DB121 is used as an instance data block:

Figure 5-3: timer_week

The Time_To_Check parameter is a structure of the UDT_timer_week (UDT2)type. It includes:

Start day

1 to 7: Sunday to Saturday

8: Monday to Friday

9: Saturday to Sunday

Start hour, start minute, start second, combined as starttime and with astructure of the times_udt (UDT6) type

End day

1 to 7: Sunday to Saturday

8: Monday to Friday

9: Saturday to Sunday

End hour, end minute, end second, combined as endtime and with a structureof the times_udt (UDT6) type

If the startday parameter has a value between 1 and 7, only a value between 1and 7 may be entered on the end day. If the startday parameter equals 8 or 9,only 8 or 9 may be entered on the end day.


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5.1.3 Month time switch

FB timer_month checks whether the current system time and the current day of

the month in the S7 CPU are within the parameterized time interval on the inputparameters of the block. If this is the case, the output will be set to 1. Otherwise,the output is 0.

The block for the timer_month FB122 month time switch is parameterized asshown in the figure below. Data block DB122 is used as an instance data block:

Figure 5-4: timer_month

The Time_To_Check parameter is a structure of the UDT_timer_month (UDT3)type. It includes:

Start day

1 to 31: Corresponds to the day of the month

32: Last day of the month


End day

1 to 31: Corresponds to the day of the month

32: Last day of the month


Note When parameterizing start day and end day, it must be considered that not everymonth has 31 days. If a function is to be executed on or until or starting from thelast day of the month, 32 must be entered instead of 28, 30 or 31. The blockchecks which month is the current month and automatically sets the end day tothe last day of this month.


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5.1.4 Year time switch

FB timer_year checks whether the current system time and the current date in the

S7 CPU are within the parameterized time interval on the input parameters of theblock. If this is the case, the output will be set to 1. Otherwise, the output is 0.

The block for the timer_year FB123 year time switch is parameterized as shownin the figure below. Data block DB123 is used as an instance data block:

Figure 5-5: timer_year

The Time_To_Check parameter is a structure of the UDT_timer_year (UDT4)type. It includes:

Start month

Start day


End month

End day



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5.2 Relative time switch

FB timer_relative sets the output to 1 if a positive edge is detected at the

EnableClock input. The output remains set to 1 until the parameterized time haselapsed.

In addition, you can parameterize whether the parameterized time restarts witheach positive edge or whether the system responds only to the first edge change.

Figure 5-6: timer_relative

The block for relative time switching has the following input parameters:

EnableClock of the BOOL type

Value = 1: Clock is enabled

Value = 0: Clock is not enabled

CheckEdge of the BOOL type

Value = 1: Each positive edge on the StartTime parameter is evaluated ->the time is restarted each time

Value = 0: The first positive edge on the StartTime parameter isevaluated. When the time has elapsed, the clock can be restarted byanother edge change at the StartTime input-

Time_To_Go

The Time_To_Go parameter is a structure of the relative_udt (UDT5) type. Itincludes:

Number of days

Number of hours

Number of minutes

Number of seconds

Reset of the BOOL type

Value = 1: Clock is reset

Value = 0: Clock is in normal mode

The block for relative time switching has the following in/out parameters:

StartTime of the BOOL type

In the event of a positive-going edge on this parameter, the clock is activated

and remains active until the time on the time_to_go parameter has elapsed.


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Control parameters for the relative time switch are EnableClock, CheckEdge,Reset and StartTime. The control parameters and the output behave towards oneanother as shown in the following pulse timing diagrams.

CheckEdge = 0:

CheckEdge = 1:

The block for the timer_relative FB124 relative time switch is parameterized asshown in the figure below. Data block DB124 is used as an instance data block:

EnableClock

CheckEdge

StartTime

Reset

Time Aktive

Output

EnableClock

CheckEdge

StartTime

Reset

Time Aktive

Output


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5.3 Additional functions

Aside from the blocks for absolute time switching and relative time switching,

blocks for the summer/-wintertime changeover and identification of holidays aresupplied.

5.3.1 Program-controlled summer-/wintertime changeover

The block for the summer-/wintertime changeover adds exactly 1 hour to thecurrent system time in the S7 CPU when wintertime is changed over tosummertime and subtracts exactly 1 hour from the current system time in theS7 CPU when summertime is changed over to wintertime. The changeover fromwintertime to summertime always takes place on the last Saturday in March. Thechangeover from summertime to wintertime takes place on the last Saturday in

October.Figure 5-7: summer_winter

The block has the following input parameters:

activ of the BOOL type

If the parameter = 1, the block will be executed. If the parameter = 0, executionof the block will be prevented.

The block has the following output parameters:

summertime of the BOOL type

Value = 1: It is summertime

Value = 0: It is wintertime

Error of the INT type

Not equal to 0 if an error has occurred during processing.


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5.3.2 Radio-controlled summer-/wintertime changeover

Instead of the block described in chapter 7.4.1, a radio clock can optionally be

used for the summer-/wintertime changeover. FB77 DCF77_FB is used for thispurpose, which evaluates the radio clock signals.

Block FB77 is included in the application example; however, it is not parameterizedin the example. At this point, it is only shown as an alternative.

Figure 5-8: DCF77_FB


SekTakt of the BOOL type One-second interval input of the DCF77 module

Data of the BOOL type Bit pattern input, data of the DCF77module

SekCPU of the BOOL type 1 Hz clock bit memory of the CPU clock

DCF77 of the Timer type Timing element for the detection of the minutemark

The block has the following output parameters:

Time zone of the BOOL type

Value = 1: It is summertime (CEST)

Value = 0: It is wintertime (CET)

Umsch_Zeitzone of the BOOL type

Value = 1: Changeover from summertime to wintertime or vice versa takesplace in one hour

Min_Puls of the BOOL typeA negative edge starts a minute and/or the clock is set

Error of the BOOL type

Value = 1: No valid message frame has been received for three minutes or alonger period of time


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5.3.3 Identification of holidays

The block checks a DB with 30 memory locations for holidays or special days and

sets an output to 1 if the current day of the S7 CPU system time matches a datein this DB.

Figure 5-9: special_days


DB_Nr of the INT type

Contains the number of the data block that stores the holidays and specialdays.

The block has the following output parameter:

special_day of the BOOL type

Value = 1: Current day is a holiday or special day

Value = 0: Current day is not a holiday or special day


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6 Operation of the Application

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6 Operation of the ApplicationThis application provides variable tables as an operating option for the time andspecial functions.

Note The individual input and output parameters of the functions have already beendescribed in chapter5Description of the Time Switching Functions.


As an operator control and monitoring option, a VAT variable table is assigned toeach absolute time switching function. These tables are

VAT_timer_day for the day time switch

VAT_timer_week for the week time switch

VAT_timer_month for the month time switch

VAT_timer_year for the year time switch

The figure below shows the VAT_timer_month variable table of FB122timer_month as an example of the operation of the absolute time switches.

Figure 6-1: VAT_timer_month

The table starts with the input parameters of the time functions. This is where thefunction can be activated or reset.

Then the start and end time of the time switch are entered.

The output parameters form the end of the variable table. The time switch statusand a possibly occurring error code are displayed here.

Inputparameters

Outputparameters

Start time of thetime switch: Fifthday, 11:21:00 h

End time of the

time switch


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Note Operation of the absolute time functions differs only in the number of parametersfor the start and end time of the time switch.

6.2 Relative time switching function

The VAT_timer_relative variable table is available as an operator control andmonitoring option for the relative time switching function.

Figure 6-2: VAT_timer_relative

Outputparameters

Inputparameters

Runtime of thetime function:One day,2 hours,

10 minutes,30 seconds


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6.3 Input of special days

The check for special days is performed using FC100 special_days. The specialdays data is stored in DB100 IDB_special_days and can be entered using the

VAT_special_days variable table.

Figure 6-3: VAT_special_days

Special day 1(06.01.2010)

Special day 2(25.12.2010)

Outputparameter


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7 Further Notes, Tips and Tricks, etc.


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7.1 How can I include several switch-on/switch-off times inone block?

Step Action Note / action

1 In the block container of the SIMATICManager, create a new FB and open it.

2 Create as many input parameters of theassociated UDT as switch-on/switch-off timesneeded (e.g., 3).

Note:When calling, interconnect the inputparameters of the new FB with the data areasthat have the structure of the required UDT.

3 In the statement section of the new FB, call theFB for the respective time function (dependingon which UDT you have used) as often as youhave configured an associated inputparameter.

4 Save the newly created FB.

5 Now call this FB in your user program, e.g.OB1.

7 Save

8 Menu: PLC -> Download Or Download icon

7.2 What do I have to do if I need more holidays or specialdays?


1 Open the DB in which the holidays andspecial days are stored (in the example:DB100).

2 Increase the number of array elements to

the desired number (30 is entered bydefault).

3 Save the DB.

4 Open the FC that checks the holidays (inthe example: FC100).


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5 Increase the loop counter. The loopcounter must be as large as the number

of array elements (by default, the loopcounter is 30).

Note:The code sequence is in network 2 of theblock.

7 Save the FC.

8 Download the block via the PLC ->

Download menu in the SIMATIC

Manager.

Or Download icon

7.3 How can I integrate a SICLOCK radio clock into theproject?

7.3.1 Introduction

The scope of this application included the explanation of the optional use of aSIPLUS radio clock. As an alternative, the SICLOCK radio clock can be used. Thepurpose of this chapter is to provide a concise description of the properties of theSICLOCK radio clock.

7.3.2 Functionality

Basically, the SICLOCK radio clock has the same functionality as SIPLUS. It isused to receive the DCF77 time signal transmitter whose signal is demodulatedand provided as a pulse for the S7. The supplied software synchronizes the S7CPU system time with the received official time.

7.3.3 Performance data

The following table lists the key data for the SICLOCK DCF77 radio receiver:

Radio frequency 77.5 kHz

Bandwidth 400 Hz

Dimensions (W x H x D) 185 x 80 x 65 mm

Sensitivity 0.3 V

Connection cable 20 m, fixed

Plug type SUBD 9-pole

Power supply Via RS232 interface

Operating temperature -10C to +50C

Degree of protection IP65


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7.3.4 Hardware components

The following hardware components are necessary to connect it to the S7-300:

Component Order no. Description/pictureSICLOCK DCFRS 2XV9450-1AR06 DCF77 receiver

9-pole DSUB plug with 5 mconnection cable

2XV9450-1AR35 For connection to SIMATIC

Optocoupler 3TX7-005-3PB54 Optional

The diagrammatic representation below shows the complete hardwareconfiguration of an S7-300 with a SICLOCK radio clock:

Figure 7-1: Hardware configuration with SICLOCK

7.3.5 Hardware connection

The SICLOCK radio clock module is wired to the power supply and the SM 321 asfollows:

PS SM 321 SICLOCK

E 0.3 Yellow (receive signal)

M Gray (cable shield)

L+ Green (supply voltage)

M Brown (signal and supply ground)


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To amplify the SICLOCK encoder signal, it may be necessary to use anoptocoupler. In this case, the following scheme is used for the wiring:

SIMATIC S7PS SM

Optocoupler SICLOCK

+1324Vdc

Green (supply voltage)

A2

0V

Brown (signal and supply ground)

Ground

Gray (cable shield)

E 0.3 14

A1 Yellow (receive signal)

Note When selecting the place of installation of the radio clock module, it should beensured that the radio clock signal is not shielded by building faades made ofmetal or similar material. The actual module must be shielded from interferencefrequencies and should not be attached directly on a metal surface.


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7.3.6 Software interface and block parameterization

The scope of delivery of the hardware includes a disk with all S7 blocks that are

necessary for the SICLOCK DCF77 Reception Service. These blocks are: FB100,DB100, SFC0, SFC39, SFC40, FC34.

The blocks must be inserted into the block folder of your S7 project.

Function block FB100 has to be called in the following blocks:

OB 1

OB 100 (startup OB)

OB 35 (10 ms cyclic interrupt)

Parameterization is performed as shown in the following table:

OB1 OB100 OB35


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8 References

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8 References

8.1 References

This list is by no means complete and only presents a selection of relatedreferences.

Table 8-1

Topic Title

/1/ STEP7 Automating with STEP7 in STL and SCL

Hans Berger

Publicis Corporate Publishing

ISBN 3-89578-113-4

/2/

8.2 Internet links

This list is by no means complete and only presents a selection of appropriateinformation.

Table 8-2

Topic Title

\1\ Reference to thedocument

http://support.automation.siemens.com/WW/view/en/21669756

\2\ Siemens I IA/DTCustomer Support

http://support.automation.siemens.com

\3\

9 History

Table 9-1

Version Date Modification

V2.0 07/2002 First edition

V2.0.1 08/2006 Error correction in week time switch, FB121

V2.1 03/2011 To simplify the example, the OP connection was removed
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