Axis Parameters

Boolean Parameters

This table is a list of Boolean supported parameters.

These parameters are read and written by the function blocks MC_ReadBoolPar and MC_WriteBoolPar.

ID

Parameter

Name

R/W

Update Rate Type

Description

1011

MC_AXIS_PARAM_IN_POSITION

Axis In-Position

Read-only

Controller

1013

MC_AXIS_PARAM_DRIVE_WARNING

Drive Warning

Read-only

EtherCAT Cyclic

Drive Warning Status. 1

1025

MC_AXIS_PARAM_REGIST_GOOD

Good Registration Mark Occurred

Read-only

EtherCAT Non-Cyclic

  • TRUE indicates a good registration mark was encountered.
  • This Boolean is automatically reset after it has been read. 2

1026

MC_AXIS_PARAM_REGIST_BAD

Bad Registration Mark Occurred

Read-only

EtherCAT Non-Cyclic

  • TRUE indicates a bad registration mark was encountered.
  • This Boolean is automatically reset after it has been read. 2

1027

MC_AXIS_PARAM_FI_OCCURRED

Fast InputClosed The inputs are taken into account at each cycle depending on the system periodicity (for example each millisecond). Under certain circumstances this can be insufficient when more accuracy is needed, or if a quick response is required from the system. To fill the gap, a drive may have some Fast Input connections (generally one or two). When an event happens that triggers a Fast Input (e.g. when a sensor sends a rising edge), the detection of a signal occurs faster (which can be 1000 times more accurate than the system periodicity). Then the timestamp associated with this input can be provided to the IPC to take corrective action Occurred

Read-only

EtherCAT Non-Cyclic

Deprecated Behavior

  • TRUE if a fast input occurred on either Capture Engine 0 or Engine 1.
  • This Boolean is automatically reset after it has been read. 3

1033

MC_AXIS_PARAM_APPLY_SUPERIMPOSED_DISTANCE

Apply Superimposed Distance

Read / Write

Controller

The default value for this parameter is FALSE.

  • The final reported position of the axis, which does include superimposed distance, may not be equal to the Position input to MC_MoveAbsolute.
  • The final reported position of the axis is equal to the Position input to MC_MoveAbsolute.

Non-Boolean Parameters

This table is a list of non-Boolean parameters currently supported.

These parameters are read and written by the function blocks MC_ReadParam and MC_WriteParam.

ID

Parameter

Name

R/W

Update Rate Type

Description

1

MC_AXIS_PARAM_CMD_POS

Command Position

Read-only

Controller

  • Axis command position – includes any command deltas from superimposed axes.
  • User units.
  • If a set position is in process due to homing or registration, there may be a 1 cycle delay.

10

MC_AXIS_PARAM_ACT_VEL

Actual Velocity

Read-only

EtherCAT Cyclic

  • Axis actual velocity
  • User unit/sec

11

MC_AXIS_PARAM_CMD_VEL

Command Velocity

Read-only

Controller

  • Axis command velocity – includes any command deltas from superimposed axes.
  • User unit/sec

1000

MC_AXIS_PARAM_PHASE_SHIFT

Phase Shift

Read-only

Controller

  • The amount of phase shift applied by MC_Phasing.
  • Slave axis' user units

1001

MC_AXIS_PARAM_SUPERIMPOSED_DISTANCE

Superimposed Distance

Read-only

Controller

1002

MC_AXIS_PARAM_MASTER_OFFSET

Master Offset

Read / Write

Controller

  • Write: The amount to increment the master offset for an active master/slave move.
    • User units.
  • Read: The amount of master offset applied.
    • User units.

1003

MC_AXIS_PARAM_SLAVE_OFFSET

Slave Offset

Read / Write

Controller

  • Write: The amount to increment the slave offset for an active master/slave move.
    • User units.
  • Read: The amount of slave offset applied.
    • User units.

1004

MC_AXIS_PARAM_MOVE_TYPE_ACTIVE

Active Move Type

Read-only

Controller

The active move type.

See Move Types.

1005

MC_AXIS_PARAM_MOVE_TYPE_NEXT

Next Move Type

Read-only

Controller

The queued (next) move type.

See Move Types.

1006

MC_AXIS_PARAM_POSITION_ERROR

Position Error

Read-only

EtherCAT Cyclic

Position error in user units.

1007

MC_AXIS_PARAM_FEEDBACK_LAST

Raw Feedback

Read-only

EtherCAT Cyclic

1008

MC_AXIS_PARAM_ROLLOVER_POSITION

Rollover

Read / Write

Controller

  • The axis rollover position is in User units.
  • If the axis is a servo axis:
    • This parameter can only be written when there are no moves in the queue. 1
    • When this parameter is changed, the new position is scaled from the old position.

In particular:

{equation}NewPosition = OldPosition * (New Rollover) / (Old Rollover){/equation}. 

1009

MC_AXIS_PARAM_VELCOMP_FACTOR

Velocity Compensation Factor

Read / Write

Controller

  • The factor used to multiply the velocity compensation value to account for the number of updates of delay in transmission of the feedback value from the drive to the control.
  • See Velocity Compensation for more information. 1 4

1010

MC_AXIS_PARAM_VELCOMP_FILTER

Velocity Compensation Filter

Read / Write

Controller

  • The number of updates to apply a change in velocity compensation.
  • See Velocity Compensation for more information. 1 4

1012

MC_AXIS_PARAM_IN_POSITION_BAND

Axis In-Position BandwidthClosed In computer networking, bandwidth often refers to a data rate measured in bits/s, for example, network throughput. The reason for the connection of data rate with the term bandwidth is that the limit to the data rate of a physical communication link is related to its bandwidth in hertz

Read / Write

Controller

The bandwidth about the command position to determine the state of the in-position flag. 2

1014

MC_AXIS_PARAM_DRIVE_STATUS

Drive Status

Read-only

EtherCAT Cyclic

  • Drive Status Word
  • Some status bits are set only at program startup.

1015

MC_AXIS_PARAM_UU_FB_RATIO_NUM

User Unit to feedback unit ratio numerator

Read-only

Static

1016

MC_AXIS_PARAM_TORQUE_ACTUAL

Actual TorqueClosed Torque is the tendency of a force to rotate an object about an axis. Just as a force is a push or a pull, a torque can be thought of as a twist

Read-only

EtherCAT Cyclic

1017

MC_AXIS_PARAM_BUS_ADDRESS

Drive Address

Read-only

Static

  • Drive address value used in EtherCAT fieldbus functions as drive address.
  • Before using in fieldbus functions, this value needs to be converted to an integer by using a convert any_to_dint / any_to_udint function. 1

1018

MC_AXIS_PARAM_SENSOR_DELAY

SensorClosed A sensor is a type of transducer that converts one type of energy into another for various purposes including measurement or information transfer Delay

Read / Write

Controller

Compensation for Physical sensorClosed A sensor is a type of transducer that converts one type of energy into another for various purposes including measurement or information transfer delay for MC_TouchProbe, in microseconds. 1

1019

MC_AXIS_PARAM_INTERP_CMD_POS

Interpolated Command Position

Read-only

Controller

  • Command position solely from this axis’s interpolator (in User units).
  • This value does not include any command deltas from other axes that are currently superimposed upon it.

1020

MC_AXIS_PARAM_INTERP_CMD_VEL

Interpolated Command Velocity

Read-only

Controller

  • Command velocity solely from this axis’s interpolator (in user units).
  • This value does not include any command deltas from other axes that are currently superimposed upon it.

1021

MC_AXIS_PARAM_REGIST_COMP

Registration Compensation

Read-only

Controller

  • The latest calculated registration compensation value.
  • This value is updated each time a good registration mark is encountered.
  • This value is in User units.

1022

MC_AXIS_PARAM_REGIST_DIST

Distance Between the Last Two Good Registration Marks

Read-only

EtherCAT Non-Cyclic

  • The distance between the last two good registration marks.
  • This value is in User units. 2

1023

MC_AXIS_PARAM_REGIST_GOOD_CNT

Number of Consecutive Good Registration Marks

Read / Write

EtherCAT Non-Cyclic

  • Number of consecutive good registration marks.
  • This value is incremented each time a good registration mark is encountered.
    • It is automatically zeroed when a bad registration mark is encountered.
  • The ability to write this parameter is provided to allow the application to zero this value. 2

1024

MC_AXIS_PARAM_REGIST_BAD_CNT

Number of Consecutive Bad Registration Marks

Read / Write

EtherCAT Non-Cyclic

  • Number of consecutive bad registration marks.
  • This value is incremented each time a bad registration mark is encountered.
    • It is automatically zeroed when a good registration mark is encountered.
  • The ability to write this parameter is provided to allow the application to zero this value. 2

1028

MC_AXIS_PARAM_UU_FB_RATIO_DEN

User units to feedback unit ratio denominator

Read-only

Static

1029

MC_AXIS_PARAM_CM_ACT_CMD_POS

Coordinated Motion Applied Command Position

Read-only

Controller

Amount of motion actually applied to the PLCopenClosed A vendor -and product- independent worldwide association active in Industrial Control and aiming at standardizing PLC file formats based on XML axis drive by Coordinated Motion commands.

1030

MC_AXIS_PARAM_CM_CMD_POS

Coordinated Motion Command Position

Read-only

Controller

Amount of motion requested of a PLCopen axis by the Coordinated Motion commands.

1031

MC_AXIS_PARAM_INGEAR_BANDWIDTH

"In Gear" bandwidth

Read / Write

Controller

  • The bandwidth about the target slave velocity where the slave axis locks onto the master axis and the InGear output turns on for the MC_GearIn function block.
  • User unit/sec
  • Default value = 0.1. 1

1032

MC_AXIS_PARAM_DRIVE_AXIS_NUMBER

Drive Axis Number

Read-only

Static

One-based number that specifies the axis on the drive.

1034

MC_AXIS_PARAM_UU_FB_RATIO

User units to feedback unit ratio

Read-only

Static

1037

MC_AXIS_PARAM_UU_REV_RATIO

User units revolution ratio

Read / Write

Controller


  • Do NOT change the user units per revolution ratio when the axis is enabled, geared, or cammed to another axis.
    Undefined behavior may result.

Notes

  1. This is a configuration parameter.
  2. There is some delay in acquiring fast input information from drives and calculating the registration marks.
    While the information is evaluated cyclically, there may be a few cycles between when the fast input occurs and the system records the registration marks.
    See Tuning Controller Performance for EtherCAT Communication Latency for more information.
  3. There is some delay in acquiring fast input information from drives and calculating the fast input position.
    While the information is evaluated cyclically, there may be a few cycles between when the fast input occurs and the system records the fast input data.
    See Tuning Controller Performance for EtherCAT Communication Latency for more information.
  4. There is some delay in acquiring the actual position values.
    While the information is evaluated cyclically, there may be a few cycles between when the actual position is updated in the drive and the system records the fast input data.
    See Tuning Controller Performance for EtherCAT Communication Latency for more information.

Update Rate Types

Update Rate Type

Description

Controller

Update rate depends on KAS application program update rate.

See Define the PLC Cycle for more information.

EtherCAT Cyclic

Update rate depends on the EtherCAT.

See EtherCAT Master Settings tab and KAS application program Define the PLC Cycle for more information about update rates.

EtherCAT Non-Cyclic

Update rate depends on the reading of the parameter through EtherCAT.

Static

Values do not change after axis is created.

User Units to Feedback Units Ratio

Parameters 1015 and 1028 are set during the MC_CreatePLCAxis function block execution.

  • These two parameters work together to form the User Units to Feedback Units Ratio (UU/FBU Ratio).
  • The drive interface units are fixed by the drive and define the drive units per revolution.
    • This is used to command the drive per the ratio.

Example 1

Where the drive interface units are set to 1048576 units per revolution, the value of the UU-per-revolution ratio is calculated as:

UU per revolution = MC_AXIS_PARAM_UU_FB_RATIO_NUM * 1048576 / MC_AXIS_PARAM_UU_FB_RATIO_DEN

Example 2

For a drive with a ration of:

  • 360 UU / 1048576 FBU generates:
    • 360 UU per revolution of the drive motor.
    • A 0.000343323 UU-to-FBU ratio.
  • 11379 UU / 1898996404 FBU generates:
    • 6.283185 UU per revolution of the drive motor.
    • A 5.99211e-6 UU-to-FBU ratio.

Example 3 - Reading the Current to Units of Amps

After reading the current using MC_ReadParam, this equation converts current to amps for a 12 amp peak drive:

MC_AXIS_PARAM_TORQUE_ACTUAL * Drive Continuous Current Rating / 1000

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