Overview

Select this tool if you want to place additional retentive or time-related function blocks on the programming interface. LOGO!Soft Comfort then displays a toolbar of special function icons:

 

Timers

 

Analog

On-delay

Analog threshold trigger

Off-delay

Analog differential trigger

On-/Off-delay

Analog comparator

Retentive on-delay

Analog watchdog

Wiping relay (pulse output)

Analog amplifier

Edge triggered wiping relay

Analog multiplexer

Symmetrical pulse generator

Pulse Width Modulator (PWM)

Asynchronous pulse generator

Mathematic instruction

Random generator

PI controller

Stairway lighting switch

Analog ramp

Multiple function switch

Analog filter (0BA7 and later versions only)

Weekly timer

Max/Min (0BA7 and later versions only)

Yearly timer

Average value (0BA7 and later versions only)

Astronomical clock (0BA7 and later versions only)

 

Miscellaneous

Stopwatch (0BA7 and later versions only)

Latching relay

 

Counter

Pulse relay

Up/Down counter

Message text (LOGO! 0BA4 and LOGO! 0BA5), Message text (LOGO! 0BA6 and LOGO! 0BA7), Message text (LOGO! 0BA8 and later versions)

Hours counter

Softkey

Threshold trigger

Shift register (0BA4 to 0BA6) , Shift register (0BA7 to 0BA8)

 

 

Mathematic instruction error detection

 

 

Float/Integer converter (LOGO! 8.FS4 and later versions only)

 

 

Integer/Float converter (LOGO! 8.FS4 and later versions only)

The LAD Editor offers you the following additional functions:

AND with edge evaluation
NAND with edge evaluation

FBD and UDF Editors: description of the blocks of special functions
The description of the blocks of special functions in the circuit program begins with timer blocks ("T"), with counter blocks ("C") and with the remaining blocks ("SF").

The LOGO! version you have selected determines these characteristics of your circuit program:

  • Available blocks

  • Parameters that you can set

This topic also describes the following tasks or characteristics of the special functions:

  • Inverting inputs

  • Block configuration

  • Reference parameters

  • Protection

  • Retentivity

Inverting inputs

You can invert individual inputs:

  • You can invert a logical "1" at a specific input to logical "0" in the circuit program.

  • You can invert a logical "0" to logical "1" in the circuit program.

To do so, right-click the input and select the invert command from the shortcut menu.

You cannot invert the inputs of output blocks.

Note
  • Unused logical inputs default to logical "0".

  • You cannot invert the inputs of a UDF block.

0BA0-0BA3:

To invert an input, use the basic function NOT

Block configuration

The block properties dialog provides you with an easy means of setting the various block parameters.

Reference functionality

You can also assign parameters to blocks with the value from other blocks. Such parameters are reference parameters.

The parameter box displays the block's parameters in a table. You can reference any parameter in the parameter box to the parameter of another function. You can use the show/hide button to change the visibility of the parameter box.

Show/hide button

Output connector

Input connector

Each parameter has an input connector and/or an output connector. You can simply use drag and drop to create a reference line between the parameter connector of one function and the parameter connector of another function. Note that you cannot connect output parameters to other output parameters.

The reference line between two parameters indicates their reference relation. You can delete the reference line to remove the reference.

LAD Editor/0BA4-0BA7:

The parameter box is not available in the LAD Editor or for 0BA4-0BA7 devices.

Follow the below steps to create a reference: 

  1. Click the "Reference" button next to a parameter in the block properties window.

  2. LOGO!Soft Comfort displays all the blocks available for providing the reference parameter.

  3. Select the block you want to refer to.

For example, if you click the "Reference" button for the Off-Delay parameter of an Off-Delay timer, you can then choose a specific block to reuse the time value of that timer.

A quick way of changing block parameters

LOGO! 0BA7 and LOGO! 0BA8 devices provide a timer reference function. With this function, you can take the current time (Ta) of a timer as the reference value (C) in other function blocks. The calculation of the reference value (C) follows the formula as shown below:

Current time (Ta)

Time base

Reference value (C)

A : B

Hours (h : m)

C = A × 60 + B

A : B

Minutes (m : s)

C = A × 60 + B

A : B

Seconds (s: 1/100s)

C = A × 100 + B

Protection

If a Protection Active check box exists for the protection of a block parameter, you can enable or lock the display and editing of this parameter in LOGO! configuration mode.

Retentivity

The switching state and counter values of SFBs can be retentive. This means that the current data values are retained, for example after a power failure, so that the function is resumed at the break position after power on. Hence, a timer is not reset, but instead the time-to-go expires.

You must set the retentivity to enable this feature for the relevant function. There are two possible settings:

  • On: Current data values are retained.

  • Off: Current data values are not retained (default).

The Hours counter is an exception, because it is always retentive.