PlcOpenDrive

Namespace

ZPlatform

FUNCTION_BLOCK PlcOpenDrive (
 [input] Axis : Tc2_MC2.AXIS_REF,
 [input] Power : Tc2_MC2.MC_Power,
 [input] Stop : Tc2_MC2.MC_Stop,
 [input] ReadDriveAddress : Tc2_MC2.MC_ReadDriveAddress)

The PlcOpenMotionControl implementation in the Zeugwerk Framework allows the function blocks that are defined in the PLCopen motion-control standard to be useable in a more object-oriented way and especially to be used as Sequences. This simplifies chaining of said function blocks to logical tasks that have to be performed when issuing commands to a drive. For details about how these sequences are used see the PLCopen Axis implementation. In fact, we suggest to not directly instantiate any of the PLCopen wrapper classes of this library. Use the PLCopen Axis implementation instead.

This particular function block serves as a "drive control" and is the main interface to Beckhoff's NC motion. The function block handles the booting phase of a drive that is controlled via NC motion and provides methods that are useful for all PLCopen Sequences. These includes functions like

• Reading parameters
• Powering the axis that is connected to the drive.
• Retrieving information about the particular drive.

This implementation is a wrapper around

• Tc2_MC2.AXIS_REF
• Tc2_MC2.MC_Power
• Tc2_MC2.MC_ReadDriveAddress

Inputs

Axis Tc2_MC2.AXIS_REF

Power Tc2_MC2.MC_Power

Stop Tc2_MC2.MC_Stop

ReadDriveAddress Tc2_MC2.MC_ReadDriveAddress

Constructor

FB_init

METHOD FB_init (
 [input] bInitRetains : BOOL,
 [input] bInCopyCode : BOOL) : BOOL

Inputs

bInitRetains BOOL

bInCopyCode BOOL

Returns

BOOL

Properties

Accelerating

PROPERTY Accelerating : BOOL

Property Value

BOOL

ActualCurrent

PROPERTY ActualCurrent : LREAL

Property Value

LREAL

ActualFollowingError

PROPERTY ActualFollowingError : LREAL

Property Value

LREAL

ActualModuloPosition

PROPERTY ActualModuloPosition : LREAL

Property Value

LREAL

ActualPosition

PROPERTY ActualPosition : LREAL

Property Value

LREAL

ActualVelocity

PROPERTY ActualVelocity : LREAL

Property Value

LREAL

AxisReference

PROPERTY AxisReference : ZCore.ZPointer

Property Value

ZPointer

ConstantVelocity

PROPERTY ConstantVelocity : BOOL

Property Value

BOOL

Decelerating

PROPERTY Decelerating : BOOL

Property Value

BOOL

DrivePowered

PROPERTY DrivePowered : BOOL

Property Value

BOOL

NegativeMovementEnabled

PROPERTY NegativeMovementEnabled : BOOL

Set or test the negative direction lock to -> movement is allowed = TRUE, movement is locked = FALSE;

Property Value

BOOL

PositiveMovementEnabled

PROPERTY PositiveMovementEnabled : BOOL

Set or test the positive direction lock to -> movement is allowed = TRUE, movement is locked = FALSE;

Property Value

BOOL

Referenced

PROPERTY Referenced : BOOL

Property Value

BOOL

Standstill

PROPERTY Standstill : BOOL

Property Value

BOOL

Methods

BootSequence

METHOD BootSequence (
 [input] startToken : ZCore.IStartToken) : BOOL

This method handles the booting sequence of a drive that is controlled with NC motion. It has to be called cyclically until the method returns FALSE. The main purpose is to detect if the NC motion drive has been linked correctly to the PLC (see Link to PLC) and if the corresponding hardware is simulated or physically available. The later information is used in IsSimulated. Please note that this method should be used in combination with HasFault to test if the booting sequence was successful or failed. As soon as the booting phase finished, which is indicated by a falling trigger of this method, the BootSequence method should no longer be called cyclically.

Inputs

startToken IStartToken

Returns

BOOL

HasFault

METHOD HasFault () : BOOL

This method returns TRUE if NC motion reports any error about the drive or its configuration. In particular, this method should be used together with BootSequence to check if booting of the drive was successful or not.

Returns

BOOL

IsEnabled

METHOD IsEnabled () : BOOL

This method returns TRUE if the axis connected to the drive is actually powered or FALSE if it is not powered. Powering a drive is achieved by the Power function block and in particular with the power sequence.

Note

The power function-block, in constrast to most other function blocks that are dealing with motion control in the PLCopen standard, has to be called cyclically. This is the reason, why the function block is instantiated in drive context instead of the power sequence

Returns

BOOL

IsSimulated

METHOD IsSimulated () : BOOL

This method returns TRUE if the drive that is Linked to the PLC is simulated (no hardware is connected or currently not in use) or if it is physically available. This information is retrieved during booting of this object.

Returns

BOOL

Read

METHOD Read ()

This method has be called cyclically to retrieve status information about the drive and axis. This includes information as

• Current velocity
• Current position
• Following error
• etc. The method is internally, automatically called during the booting phase, but has to be called manually as soon as this phase has finished. The later is indicated by the first time that BootSequence returns FALSE.

Write

METHOD Write ()

This method has be called cyclically to keep an axis that has been enabled (e.g. by using PlcOpenPowerSequence) powered.