AbsA (FB)

FUNCTION_BLOCK AbsA

Short Description

Anti-blocking protection for an analog signal

Portrayal

Interfaces

Inputs

Name	Datatype	Range	Init-Value	Function
rPosFb	REAL			Position feedback

Outputs

Name	Datatype	Range	Init-Value	Function
rOut	REAL			Analog - output
xAbsOn	BOOL			Anti-blocking protection process
dtAbsLastOn	DATE_AND_TIME			Startdate / -Timepoint of the last anti-blocking protection process

Setpoints / Parameters

Name	Datatype	Range	Init-Value	Function
rMinChange	REAL		10.0	Minimum position change
tTime	TIME		180s	Time duration of the anti-blocking protection process
eDay	eDoW		eDow.Monday	Weekday of anti-blocking operation
todStartTime	TOD		08:00:00 Uhr	Time point of the anti-blocking protection process
rMinLimit	REAL		0	Lower limit for the analog - output rOut
rMaxLimit	REAL		100	Upper limit for the analog - output rOut

Functional Description

General

This function block is used to monitor the analog input rPosFb to activity. The test period covers 168 hours (= 1 week).

The position feedback rPosFb is active if its value has changed in the check period by an amount greater than the minimum position change rMinChange.

The blocking protection process is thereby suppressed (= blocking protection process not active), the test time starts again.

If no activity was detected during the test period, the blocking protection process is triggered with the tTime time period on the eDay weekday

at todStartTime time. (= blocking protection process active). At the same time, the test period starts again.

During the blocking protection process, different signals are shown at the analog output rOut depending on the current value at the position feedback rPosFb, at the beginning of the blocking protection process.

Condition 1: rPosFb > 51% of the upper limit for the analog output rOut:

rOut = rMinLimit

Condition 2: rPosFb <= 51% of the upper limit for the analog output rOut:

rOut = rMaxLimit

If the blocking protection process is disabled, the analog output rOut shows 0.0.

The initial triggering of the blocking protection process may vary depending to the relevant settings (eDay weekday and todStartTime)

(example: test time ended on Tuesday morning, triggering of the blocking protection process only on the next Monday).

At the dtAbsLastOn output, the start date and the start time of the last blocking protection process are available.

Voraussetzung für den Einsatz des Funktionsbausteins AbsA

For correct function, the use of the function block TimeRead with xEn = TRUE is mandatory.

Display of the blocking protection process xAbsOn

This output is used to display an active blocking protection process (xAbsOn = TRUE).

Setpoint / Parameter eDay

Die Blockierschutzfunktion kann durch die Einstellung eDay = eDow.Inactive generell gesperrt werden.

Setpoint / Parameter**tTime**

The blocking protection function can be disabled by set the setting to tTime = 0s.

Visualization

Information

Element	Authors	Date	Version	Notes
Function	Adam Bartod	06.2016	1.0	Initial version
Programming	Adam Bartod	06.2016	1.0	Initial version
Test	Jochen Reu	02.2017	1.0	Initial version
Documentation	Jochen Reu	10.2017	1.0	Initial version

Codesys

InOut:

Scope	Name	Type	Initial	Comment
Input	rPosFb	REAL		Position feedback
	rMinChange	REAL	10	Minimum position change
	tTime	TIME	TIME#3m0s0ms	Time duration of the anti-blocking protection process
	eDay	eDoW	eDow.Monday	Weekday of anti-blocking operation
	todStartTime	TOD	TIME_OF_DAY#8:0	Time point of the anti-blocking protection process
	rMinLimit	REAL	0	Lower limit for the analog - output rOut
	rMaxLimit	REAL	100	Upper limit for the analog - output rOut
Output	rOut	REAL		Analog - output
	xAbsOn	BOOL		Anti-blocking protection process
	dtAbsLastOn	DT		Startdate / -Timepoint of the last anti-blocking protection process

• AbsA.mEx (METH)
  • Kurzbeschreibung Methode (AbsA.mEx)