FB_Cylinder

Description

This function block can be used to control a cylinder and the Limit Switches.

There are two inputs InA and InB to set the direction of the movement and the belonging LimSwitches LsA and LsB.

If InA is set to TRUE the output DirA is set to TRUE and after a time value defined by CtrlTime the LsA has to become TRUE otherwise a fault FaultLsA appears. Just as in direction B.

If both LsA and LsB are TRUE then a Fault depending of the output is set. If both InA and InB are given (e.g. to stop the cylinder movement) no limit switch is controlled.

All faults can be reset by input iResetFault.

Arguments

Input

iInA	Description	Set direction A
	Data type	BOOL
iInB	Description	Set direction B
	Data type	BOOL
iLsA	Description	Limit Switch at End of direction A
	Data type	BOOL
iLsB	Description	Limit Switch at End of direction B
	Data type	BOOL
iCtrlTime	Description	Max Time till Lim.Sw. has to be reached
	Data type	TIME
iResetFault	Description	Reset Fault (Is set to FALSE by UDFB"User Defined Function Block" UDFB can be used as a sub-function block in another program of the application. It is described using FBD, LD, ST or IL language. Input / output parameters of a UDFB (as well as private variables) are declared in the variable editor as local variables of the UDFB!)
	Data type	BOOL

Output

oDirA	Description	Direction A
	Data type	BOOL
oDirB	Description	Direction B
	Data type	BOOL
oFaultLsA	Description	Fault of Lim.Sw. at End direction A
	Data type	BOOL
oFaultLsB	Description	Fault of Lim.Sw. at End direction B
	Data type	BOOL

Usage

The signal flow is valid for both directions (A and B)

If oDirA AND oDirB are active there is no Fault Control.

The Fault can be reset by iRestFault = True.

Example

ST

//Electric Cylinder with limit switch controls
Inst_FB_Cylinder( dirA, dirB, LimitSwitchA, LimitSwitchB, CtrlTime, ResetFault );
A := Inst_FB_Cylinder.oDirA;
B := Inst_FB_Cylinder.oDirB;
FaultLimitSwitchA := Inst_FB_Cylinder.oFaultLsA;
FaultLimitSwitchB := Inst_FB_Cylinder.oFaultLsB;

Function Block Diagram

UDFB Cylinder: FBD example

FFLD

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