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SINUMERIK 840D sl. Service - Functions. Manual (2018-2020) - page 8

Positioning axes

8.7 Control by the PLC

8.7.1

Starting concurrent positioning axes from the PLC

Traversing an axis in the NC as competing positioning axes from the PLC user program is realized

using block FC18:

The following functions are defined:

• Linear interpolation (G01)

• Feedrate in mm/min or degrees/min (G94)

• Exact stop (G09)

• The active adjustable work offsets are taken into account

Since each axis is assigned to exactly one channel, the control can select the correct channel

from the axis name/axis number and start the concurrent positioning axis on this channel.

Further information

Function Manual PLC; Block descriptions > FC18: SpinCtrl, spindle control

8.7.2

PLC-controlled axes

PLC actions

The table below compares the following PLC actions as response of the NC for a machine axis:

• Start machine axis as PLC axis using FC18

• Initiate NC start or NC stop

• Axis-specific STOP, RESUME or RESET

• Trigger NC-RESET

• Cancel or set controller enable for the machine axis

• Relinquish control of machine axis to NC

Examples of NC responses

PLC actions as response of the NC are listed in the table below.

PLC actions

NC response

Machine axis AX1 is the channel axis in channel

1, start as PLC axis using FC18

Initiate NC stop axes and spindles

AX1 is stopped.

DB21, ... DBX7.4 = 1 (NC stop axes plus spindle)

DB21, ... DBX7.1 = 1 initiate (NC start)

AX1 continues to traverse.

The PLC wants to control AX1,

Checking AX1 is relinquished to the PLC. DB31, ...

DBX63.1 = 1 (PLC controls the axis)

DB31, ... DBX28.7 = 1 (PLC controls axis)

Initiate NC stop for axes and spindles

AX1 is not stopped.

DB21, ... DBX7.4 = 1 ("NC stop axes plus spindle")

Axes and spindles

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8.7 Control by the PLC

PLC actions

NC response

Initiate axial stop

AX1 is stopped

DB31, ... DBX63.2 ==1 (axis stop active)

DB31, ... DBX28.6 = 1 (stop along braking ramp)

Initiate axial continuation

AX1 traverses further

DB31, ... DBX63.2 == 0 (axis stop active)

DB31, ... DBX28.2 = 1 (continue)

Initiate NC RESET

No effect on AX1

DB21, ... DBX7.7 = 1 initiate (reset)

Initiate axial reset

AX1 is stopped and the traversing motion is inter-

rupted:

DB31, ... DBX28.1 = 1 (reset)

• DB31, ... DBX63.2 = 0 (axis stop active)

• Read-in axial machine data

• DB31, ... DBX63.0 = 1 (reset executed)

• DB31, ... DBX63.2 = 0 (axis stop active)

Start machine axis AX1 as PLC axis via FC 18

DB31, ... DBX63.0 = 0 (reset executed)

Withdraw controller enable for AX1:

Alarm 21612 "Axis %1 measuring system change"

is displayed

DB31, ... DBX2.1 = 0 (controller enable)

Initiate axial continuation

• Alarm 21612 "Axis %1 measuring system

DB31, ... DBX28.2 = 1 (continue)

change" is deleted

• DB21, ... DBX40.7 = 1(traversing command

plus)

• AX1 does not traverse due to a missing control-

ler enable signal.

Set controller enable for AX1

AX1 moves to the programmed end point.

DB31, ... DBX2.1 = 1 (controller enable)

Initiate axial reset

• Stop AX1

DB31, ... DBX28.1 = 1 (reset)

• Read-in axial machine data

• DB31, ... DBX63.0 = 0 (reset)

PLC relinquishes control of AX1 to the NC from

• NC accepts control of machine axis

DB31, ... DBX28.7 = 0 (PLC controls axis)

• DB31, ... DBX63.1 = 0 (PLC controls the axis)

• DB31, ... DBX63.0 = 0 (reset)

8.7.3

Control response of PLC-controlled axes

Response for a channel reset, activate machine data, block search and MD30460

Table 8-1

Control response to

PLC-controlled axis

Mode change and NC program control

Work independently of axis.

Channel RESET

No axial machine data are effective and a traversing

movement is not aborted.

NEWCONF

No axial machine data are effective.

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Positioning axes

8.7 Control by the PLC

Control response to

PLC-controlled axis

Block search Type 5 SERUPRO

Are processed during SERUPRO to simulate the nor-

mal procedure, e.g. PLC takes over or relinquishes

control of this axis which is also traversing via the

PLC.

All block search variants

The PLC takes over control of the axis before the

of types 1, 2, 4 and 5

approach block and is responsible for positioning

this axis.

NC-controlled retraction activated with

Has no effect and acts only on the specified PLC-

$AC_ESR_TRIGGER.

controlled axis.

Machine data:

Which is not controlled

MD30460 $MA_BASE_FUNKTION_MASK

exclusively by the PLC

Bit 4 = 0

Cannot be changed directly with axis replacement

command GET (axis) or AXTOCHAN (axis, channel)

to an axis controlled by the NC program.

Bit 4 = 1

Cannot be requested for the NC program. GET or

AXTOCHAN from the NC program or a synchronized

action, or programming the axis in the NC program,

are rejected with alarm 26075.

MD30460 $MA_BASE_FUNKTION_MASK

For the PLC-controlled axis

Bit 6 = 1

Channel-specific

IS DB 21, ... DBX6.0 ("feed disable") is not effective.

This axis is not stopped when feed disable is acti-

vated, but continues to move.

Bit 7 = 1

The axis is not taken into account when

IS DB 21, ... DBX36.3 ("all axes stationary") is gen-

erated. This signal is output with 1 even if all other

axes in the channel are stationary and only the PLC-

controlled axis is active.

* Note on axis replacement

This replacement of a "neutral axis" by an "NC program axis" does not take place until the PLC has

really relinquished control of the axis in accordance with use case "Relinquish control of axis".

8.7.4

Control response of PLC-controlled axes

Response for a channel reset, activate machine data, block search and MD30460

Table 8-2

Control response to

PLC-controlled axis

Mode change and NC program control

work independently of axis.

Channel RESET

No axial machine data are effective and a traversing

movement is not aborted.

NEWCONF

No axial machine data are effective.

Axes and spindles

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Positioning axes

8.8 Response with special functions

Control response to

PLC-controlled axis

Block search Type 5 SERUPRO

are processed during SERUPRO to simulate the nor-

mal procedure, e.g. PLC takes over or relinquishes

control of this axis which is also traversing via the

PLC.

All block search variants

The PLC takes over control of the axis before the

of types 1, 2, 4 and 5

approach block and is responsible for positioning

this axis.

NC-controlled retraction activated with

has no effect and acts only on the specified PLC-

$AC_ESR_TRIGGER.

controlled axis.

machine data:

which is not controlled

MD30460 $MA_BASE_FUNKTION_MASK

exclusively by the PLC

Bit 4 = 0

cannot be changed directly with axis replacement

command GET (axis) or AXTOCHAN(axis, channel)

to an axis controlled by the NC program, see * Note

on axis replacement.

Bit 4 = 1

cannot be requested for the NC program. GET or

AXTOCHAN from the NC program or a synchronized

action, or programming the axis in the NC program,

are rejected with alarm 26075.

MD30460 $MA_BASE_FUNKTION_MASK

For the PLC-controlled axis

Bit 6 = 1

channel-specific

IS DB 21, ... DBX6.0 ("feed disable") is not effective.

This axis is not stopped when feed disable is acti-

vated, but continues to move.

Bit 7 = 1

the axis is not taken into account when

IS DB 21, ... DBX36.3 ("all axes stationary") is gen-

erated. This signal is output with 1 even if all other

axes in the channel are stationary and only the PLC-

controlled axis is active.

* Note on axis replacement

This replacement of a "neutral axis" by an "NC program axis" does not take place until the PLC has

really relinquished control of the axis in accordance with use case "Relinquish control of axis".

Waiting for this axis interchange is displayed on the HMI operator panel front.

8.8

Response with special functions

8.8.1

Dry run (DRY RUN)

The dry run feedrate is also effective for positioning axes unless the programmed feedrate is

larger than the dry run feedrate.

Activation of the dry run feed entered in SD42100 $SA_DRY_RUN_FEED can be controlled with

SD42101 $SA_DRY_RUN_FEED_MODE. See

Further information

Feedrates (Page 195)

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Positioning axes

8.10 Data lists

X

Q1

Q2

N20

N30

N

45 N50

N55

N60

N70 N

7

5 N80

X

path axes

Q1, Q2

positioning axes

Figure 8-4

Timing of path axes and positioning axes

8.10

Data lists

8.10.1

Machine data

8.10.1.1

NC-specific machine data

Number Identifier: $MN_

Description

18960

POS_DYN_MODE

Type of positioning axis dynamic response

8.10.1.2

Channelspecific machine data

Number Identifier: $MC_

Description

20730

G0_LINEAR_MODE

Interpolation behavior with G0

20732

EXTERN_G0_LINEAR_MODE

Interpolation behavior with G00

22240

AUXFU_F_SYNC_TYPE

Output timing of F functions

8.10.1.3

Axis/spindlespecific machine data

Number Identifier: $MA_

Description

30450

IS_CONCURRENT_POS_AX

Concurrent positioning axis

30460

BASE_FUNCTION_MASK

Axis functions

32060

POS_AX_VELO

Feedrate for positioning axis

32300

MAX_AX_ACCEL

Maximum axis acceleration

32430

JOG_AND_POS_MAX_JERK

Maximum axial jerk for positioning axis movements

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8.10 Data lists

Number Identifier: $MA_

Description

32431

MAX_AX_JERK

Maximum axial jerk for path movements

37510

AX_ESR_DELAY_TIME1

Delay time for ESR single axis

37511

AX_ESR_DELAY_TIME2

ESR time for interpolatory braking of single axis

8.10.2

Setting data

8.10.2.1

Axis/spindle-specific setting data

Number Identifier: $SA_

Description

43600

IPOBRAKE_BLOCK_EXCHANGE

Braking ramp block change condition

43610

ADISPOSA_VALUE

Braking ramp tolerance window

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Rotary axes

9.1 Brief description

• Assignment: A rotates about X, B rotates about Y and C rotates about Z

• Direction of rotation: The positive rotary-axis direction of a rotation corresponds to a

clockwise rotation when looking in the positive axis direction of the corresponding linear

axis.

:

#

࢕9

࢕;

"

$

;

9

࢕:

Figure 9-1

Axis identifiers and directions of movement for rotary axes

Units of measurement

The following units of measurement apply as standard to inputs and outputs for rotary axes:

Units of measurement for rotary axes

Physical quantity

Unit

Angular position

Degrees

Programmed angular velocity

Degrees/min

Angular velocity

¹⁾ rev/min

Angular acceleration

¹⁾ rev/sec²

Angular jerk limit

¹⁾rev/sec³

1) Unit of the axis-specific machine data for rotary axes.

Further information

Velocities, setpoint/actual value systems, closed-loop control (Page 135)

Feedrate

The programmed feedrate F corresponds to an angular velocity (degrees/min) in the case of

rotary axes.

If rotary axes and linear axes traverse a common path with G94 or G95, the feedrate should be

interpreted in the linear-axis unit of measurement (e. g. mm/min, inch/min].

The tangential velocity of the rotary axis refers to diameter D_unit (unit diameter D_unit=360/π). In

the case of unit diameter D=D_unit, the programmed angular velocity in degrees/min and the

tangential velocity in mm/min (or inch/min) are numerically identical.

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Rotary axes

9.2 Modulo 360 degrees

In general, the following applies for tangential velocity:

F = F_angle * D/D_unit

F

= Tangential velocity [mm/min]

F_angle

= Angular velocity [degrees/min]

D

= Diameter acted on by F [mm]

With D_unit = 360/π

D_E

= Unit diameter [mm]

π

= Circle constant Pi

JOG mode: Revolutional feedrate

In the JOG mode, the response of the rotary axis spindle also depends on the setting data:

SD41100 $SN_JOG_REV_IS_ACTIVE (revolutional feed rate for JOG active)

9.2

Modulo 360 degrees

A 360° modulo rotary axis is a rotary axis whose position is mapped to the range from 0° to

359.999°. As a consequence, in principle, the traversing range of a 360° modulo rotary axis is

infinity. The traversing range limits (software limit switch and working area limits) of 360°

modulo rotary axes are not effective.

In the diagram below, the absolute position of a rotary axis in the positive direction of rotation

is represented as a spiral. The pointer to the spiral indicates the absolute position of the rotary

axis (420°). The point where the pointer intersects with the modulo circle marks the

corresponding 360° modulo position (60°).

p

p

p

p

p

p

p

p

p

࢕

p

p

p

p

p

p

Figure 9-2

Modulo_mapping

Parameter assignment

Modulo function

The modulo function for a rotary axis is activated using the axis-specific machine data:

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Rotary axes

9.2 Modulo 360 degrees

MD30310 $MA_ROT_IS_MODULO = 1

Note

For a 360° modulo rotary axis, it is recommended that the position display is also set to 360° at

the user interface.

Modulo range

For a 360° modulo rotary axis, the modulo range must be set to 360° using the axis-specific

machine data:

MD30330 $MA_MODULO_RANGE = 360.0

Starting position of the 360° modulo range

The starting position of the 360° modulo range can be set using the axis-specific machine data:

MD30340 $MA_MODULO_RANGE_START = <Starting position>

As a consequence, the parameterized starting position represents an offset of the modulo

function in the vertical axis. The modulo range still remains 360°.

Examples

• Standard starting position: 0° ⇒ modulo range: 0° - 360°

• Shifted starting position: -180° ⇒ modulo range: -180° to +180°

p

p

p

࢕

p

࢕

p

࢕

p

࢕

p

p

p

p

p

࢕

p

࢕

p

① Absolute position

② Modulo position

③ Shifted starting position (-180°)

Figure 9-3

Standard and shifted starting position (red)

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Rotary axes

9.2 Modulo 360 degrees

Note

Modulo partition axes

By aligning the two following machine data, indexing positions of 360° modulo indexing axes

can be implemented in the same way as for the 360° modulo range:

• MD30503 $MA_INDEX_AX_OFFSET

• MD30340 $MA_MODULO_RANGE_START

See the examples in Chapter "Indexing axes, "Example 3: Rotary modulo axis as equidistant

indexing axis (Page 340)" and the following chapters.

360° modulo rotary axis: Positioning behavior for G90 (modal absolute programming)

The standard behavior for G90 is set via the machine data:

MD30455 $MA_MISC_FUNCTION_MASK, bit 2 = <value>

<value>

Meaning

0

The 360° modulo rotary axis positions corresponding to AC as standard for G90 program-

ming:

• Target position > Current position: Move in positive traversing direction

• Target position < Current position: Move in negative traversing direction

1

For G90 programming, the 360° modulo rotary axis positions as standard corresponding

to DC, i.e. the shortest path.

Position display in the 360° modulo representation

Activating the position display at the user interface in the 360° modulo representation is realized

using the axis-specific machine data:

MD30320 $MA_DISPLAY_IS_MODULO = 1

NC/PLC interface signals

Activating the traversing range limits

In principle, the traversing range of a 360° modulo rotary axis is infinity. This is the reason that

axis-specific traversing range limits to not apply as standard, such as software limit switches and

working error limits. The traversing range limits of a 360° modulo rotary axis can be activated

using the subsequent absolute axis-specific NC/PLC interface signal, possibly initiated via an M/

H function in the NC program:

DB31, ... DBX12.4 = 1 (360° modulo rotary axes: Activate traversing range limits)

Axes and spindles

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Rotary axes

9.2 Modulo 360 degrees

p

p

p

p

࢕

p

p

① Direction of rotation +/-

② Software limit switch +/-

Figure 9-4

360° modulo rotary axis with software limit switch

Feedback signal, activation of the traversing range limits

The feedback signal that the traversing range limits of a 360° modulo rotary axis are active in the

NC, is realized using the axis-specific NC/PLC interface signal:

DB31, ... DBX74.4 == 1 (modulo rotary axes: traversing range limits active)

Example: Changing the traversing range limits

Pallet 1 with several clamped workpieces is machined on a 360° modulo rotary axis. The pallet

1 is then swapped for a pallet 2 with a built-on axis. The traverse range now has to be monitored.

Parameterization:

• MD30300 $MA_IS_ROT_AX[ AX5 ] = 1

• MD30310 $MA_ROT_IS_MODULO[ AX5 ] = 1

• MD36110 $MA_POS_LIMIT_PLUS[ AX5 ] = 340

• MD36100 $MA_POS_LIMIT_MINUS[ AX5 ] = 350

Extract from part program:

Program code

Comment

M123

; Insert pallet 1 with quadruple clamping

; PLC: deactivate traversing range limits of the

; B axis => DB35, DBX12.4=0

STOPRE

; Trigger a preprocessing stop

S1000 M3

G4 F2

G1 X0 Y300 Z500 B0 F5000

CYCLE84(500,400,0,350,0,1,4,10,,0,500,1000) ; drilling cycle

G0 Z540 B0

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Rotary axes

9.3 Programming of rotary axes

Program code

Comment

M124

; Insert pallet 2 with built-on axis

; PLC: activate traversing range limits of the

; B axis => DB35, DBX12.4=1

STOPRE

; Trigger a preprocessing stop

B270

9.3

Programming of rotary axes

9.3.1

General information

Note

For information about programming, see the NC Programming Programming Manual.

MD30310

Axis-specific machine data is used to define whether a rotary axis behaves as a linear axis during

programming and positioning, or whether rotary-axis special features should be taken into

account:

MD30310 $MA_ROT_IS_MODULO (modulo conversion for rotary axis)

These features and any differences (mainly with respect to absolute programming) are

explained on the following pages.

Modulo display for rotary axes and spindles

MD30320 $MA_DISPLAY_IS_MODULO (modulo display for rotary axis or spindle)

If MD30310 and MD30320 are set to "1", the change to a modulo display takes place as soon as

the actual value display changes between 0° and 359.999° - or exceeds 359.999° in the positive

direction of rotation, or falls below 0° in the negative direction of rotation.

For internal setpoint and actual values, the behavior of rotary axes and spindles differ:

• For spindles, the modulo conversion takes place for each spindle programming (M3, M4 and

M5).

• For rotary axes, the modulo conversion only takes place with a new traversing command.

If the setpoint and actual values are read out, these are the same as the display values in the

"Service overview" - "Service axis" under the selected axis. For rotating spindles or rotary axes,

these values can also lie below the modulo range of 0° to 359.999°.

Axes and spindles

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Rotary axes

9.3 Programming of rotary axes

p

p

p

࢕

p

p

p

p

① POS[C] = ACP(100); Traverse in positive direction of rotation to

position 100°

② POS[C] = ACN(300); Traverse in negative direction of rotation to

position 300°

③ POS[C] = ACP(240); Traverse in positive direction of rotation to

position 240°

④ POS[C] = AC(0); Traverse in negative direction of rotation to position

0°

Figure 9-5

Absolute programming for modulo rotary axes

Absolute programming along the shortest path (DC)

Example of absolute programming on the shortest path for a modulo rotary axis as positioning

axis:

POS[<axis name>] = ACP(<value>)

• <value>: Target position of the modulo rotary axis in the range between 0° and 359.999°

Negative values are also possible if a range offset has been realized with the following

machine data:

- MD30340 $MA_ MODULO_RANGE_START

- MD30330 $MA_MODULO_RANGE

• DC: Absolute programming of the target position for moving by the shortest direction of

rotation.

Note

If the route is the same in both directions (180°), movement in in the positive direction of

rotation.

Programming examples

Starting position of modulo rotary axis C = 0° (see figure below).

Axes and spindles

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Rotary axes

9.3 Programming of rotary axes

p

p

p

p

࢕

p

p

p

p

① POS[C] = DC(100); Traverse by shortest path to position 100°

② POS[C] = DC(300); Traverse by shortest path to position 300°

③ POS[C] = DC(240); Traverse by shortest path to position 240°

④ POS[C] = DC(60); Traverse by shortest path to position 60°

; in positive direction of rotation

Figure 9-6

Absolute programming with shortest path for modulo rotary axes

Block-search response

After block search with calculation, the collected search run positions can be read by modulo,

converted using the system variable $AC_RETPOINT[<axis>].

Supplementary conditions for ASUB after block search with calculation

In this instance, as well as with the cross-channel block-search tool SERUPRO, the modulo

conversion simulated in the block search must be performed in the part program.

Incremental programming (IC, G91)

Example for positioning axis: POS[axis name] = IC(+/-value)

• The value identifies the rotary-axis traversing distance. The value can be negative and ≥

+/-360°.

• The value's sign unequivocally defines the rotary-axis traversing direction.

• Application example: milling a spiral groove across several revolutions

Example

Programming

Effect

POS[C]=IC(720)

C axis traverses to 720° incrementally in the positive direction

(two revolutions)

POS[C]=IC(-180)

C axis traverses to 180° incrementally in the negative direction

Program example: Modulo rotary axes as endlessly rotating rotary axis

Program code

LOOP:

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Rotary axes

9.3 Programming of rotary axes

Program code

POS[C] = IC(720) ; Traverse as positioning axis by 270°

GOTOB LOOP

; Return to Label LOOP

9.3.3

Rotary axis without modulo conversion

Deactivating modulo conversion

→ set MD30310 $MA_ROT_IS_MODULO = 0.

Absolute programming (AC, G90)

Example for positioning axis: POS[axis name] = AC (+/- value)

• The value and its sign uniquely identify the rotary-axis target position. The value can be ≥

+/-360°. The position value is limited by the software limit switch positions.

• The traversing direction is defined by the control according to the signed rotary axis actual

position.

• If ACP or ACN is programmed, alarm 16810, "ACP traverse instruction cannot be used", or

alarm 16820 "ACN traverse instruction cannot be used", is output.

• Application example:

Linear motion (cam gear) are coupled to the rotary axis, thus certain end positions may not

be passed.

Example:

Programming

Effect

POS[C] = AC (-100)

Rotary axis C traverses to position -100°;

traversing direction depends on the starting position

POS[C] = AC (1500)

Rotary axis C traverses to position 1500°

Absolute programming along the shortest path (DC)

POS[axis name] = DC(value)

Even if the rotary axis is not defined as a modulo axis, the axis can still be positioned with DC

(Direct Control). The behavior is the same as that of a modulo axis.

• The value identifies the rotary axis target position in a range from 0° to 359.999° (modulo

360°). Alarm 16830, "Incorrect modulo position programmed", is output for values with a

negative sign or ≥ 360º.

• With DC (Direct Control), the rotary axis approaches the programmed absolute position

within one revolution along the shortest path (traversing movement max. ±180°).

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Rotary axes

9.3 Programming of rotary axes

• The control calculates the direction of rotation and the traverse path according to the current

actual position (in relation to modulo 360°). If the path to be traversed is the same in both

directions (180°), the positive direction of rotation has priority.

• DC application example: the rotary table is required to approach the changeover position in

the shortest time (and, therefore, via the shortest path) possible.

• If DC is programmed for a linear axis, alarm 16800, "DC traverse instruction cannot be used",

is output.

Example:

Programming

Effect

POS[C] = AC (7200)

Rotary axis C traverses to position 7200°;

traversing direction depends on the starting position

POS[C] = DC (300)

Rotary axis C approaches "modulo" position 300°

along the shortest path

Thus, C traverses through 60° with a negative direction of rotation

and stops at absolute position 7140°.

POS[C] = AC (7000)

Rotary axis C traverses to position 7000° absolute,

C traverses through 140° with a negative direction of rotation

Note

In this example, it would be advisable to activate the modulo 360º display (MD30320

$MA_DISPLAY_IS_MODULO = 1).

Incremental programming (IC, G91)

Example for positioning axis: POS[axis name] = IC(+/- value)

When programming with incremental dimensions, the rotary axis traverses along the same path

as for the modulo axis. In this case, however, the traversing range is limited by the software limit

switches.

• The value identifies the rotary axis traversing distance.

The value can be negative and ≥ +/-360°.

• The sign of the value defines the rotary axis traversing direction.

Limited traversing range

The traversing range is limited just the same as for linear axes. The range limits are defined by

the "plus" and "minus" software limit switches.

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Rotary axes

9.4 Activating rotary axes

9.3.4

Other programming features relating to rotary axes

Offsets

TRANS (absolute) and ATRANS (additive) can be applied to rotary axes.

Scalings

SCALE or ASCALE are not suitable for rotary axes, since the control always bases its modulo

calculation on a 360º full circle.

Preset actual value memory

PRESETON is possible.

Indexing axes

See Section "Indexing axes (Page 325)".

9.4

Activating rotary axes

Procedure

The procedure for activating rotary axes is the same as that for linear axes with a small number

of exceptions. It should be noted that, as soon as the axis is defined as a rotary axis (MD30300

$MA_IS_ROT_AX = 1), the axis-specific-machine-/setting-data units are interpreted by the

control as follows:

Positions

In "degrees"

Velocities

In "rev/min"

Accelerations

In "rev/sec²"

Jerk limitation

In "rev/sec³"

Special machine data

Special rotary-axis machine data may also have to be entered, depending on the application:

MD30310 $MA_ROT_IS_MODULO

Modulo conversion for positioning and program-

ming

MD30320 $MA_DISPLAY_IS_MODULO

Modulo conversion for position display

MD10210 $MN_INT_INCR_PER_DEG

Computational resolution for angular positions

Axes and spindles

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Rotary axes

9.4 Activating rotary axes

The following overview lists the possible combinations of these machine data for a rotary axis:

Possible combinations of rotary-axis machine data

MD30300

MD30310

MD30320

Application

Comment

permitted

0

0

0

Yes

The axis is a linear axis (default).

1

0

0

Yes

The axis is a rotary axis; modulo conversion

is not used for positioning, i.e. the software

limit switches are active; the position dis-

play is absolute.

1

0

1

Yes

The axis is a rotary axis; modulo conversion

is not used for positioning, i.e. the software

limit switches are active; the position dis-

play is modulo;

application: for axes with an operating

range of +/-1000°, for example

1

1

1

Yes

The axis is a rotary axis; positioning is per-

formed with modulo conversion, i.e. the

software limit switches are inactive, the

operating range is unlimited; the position

display is modulo (setting most frequently

used for rotary axes); axis with/without

working-area limitation can be used.

1

1

0

Yes

The axis is a rotary axis; positioning is per-

formed with modulo conversion, i.e. the

software limit switches are inactive, the

operating range is unlimited; the position

display is absolute; axis with/without work-

ing-area limitation can be used.

0

0 or 1

0 or 1

Not recom-

Axis is not a rotary axis;

mended

therefore, the other MD are not evaluated.

JOG velocity for rotary axes

SD41130 $SN_JOG_ROT_AX_SET_VELO (JOG speed for rotary axes)

The above setting data can be used to define a valid JOG velocity for all rotary axes (see also

Section "Manual traversing (Page 695)").

If a value of 0 is entered in the setting data, the following axial machine data acts as JOG velocity

for the rotary axis:

MD21150 $MC_JOG_VELO (conventional axis velocity)

Axes and spindles

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Rotary axes

9.7 Data lists

9.6

Examples

Fork head, inclined-axis head

Rotary axes are frequently used on 5-axis milling machines to swivel the tool axis or rotate the

workpiece. These machines can position the tip of a tool on any point on the workpiece and take

up any position on the tool axis. Various milling heads are required, depending on the

application. The figure shows a fork head and an inclined-axis head as example rotary-axis

arrangements.

'PSL IFBE

*ODMJOFE BYJT IFBE

Figure 9-7

Fork head, inclined-axis head

9.7

Data lists

9.7.1

Machine data

9.7.1.1

General machine data

Number

Identifier: $MN_

Description

10210

INT_INCR_PER_DEG

Computational resolution for angular positions

Axes and spindles

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Rotary axes

9.7 Data lists

9.7.1.2

Axis/spindlespecific machine data

Number

Identifier: $MA_

Description

30300

IS_ROT_AX

Axis is rotary axis

30310

ROT_IS_MODULO

Modulo conversion for rotary axis

30320

DISPLAY_IS_MODULO

Actual value display modulo

30330

MODULO_RANGE

Modulo-range size

30340

MODULO_RANGE_START

Modulo-range starting position

30455

MISC_FUNCTION_MASK

Axis functions

36100

POS_LIMIT_MINUS

Minus software limit switch

36110

POS_LIMIT_PLUS

Plus software limit switch

9.7.2

Setting data

9.7.2.1

General setting data

Number

Identifier: $SN_

Description

41130

JOG_ROT_AX_SET_VELO

JOG velocity for rotary axes

9.7.2.2

Axis/spindle-specific setting data

Number

Identifier: $SA_

Description

43420

WORKAREA_LIMIT_PLUS

Plus working-area limitation

43430

WORKAREA_LIMIT_MINUS

Minus working-area limitation

Axes and spindles

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Indexing axes

10.2 Detailed description

immediately stopped when the traversing key is actuated again (second rising edge). Under

certain circumstances, the indexing axis is then not located at an indexing position. Traversing

motion is continued at the indexing position by again actuating the traversing key.

Revolutional feedrate

The revolution feedrate with which the indexing axis is traversed in the JOG mode is dependent

on:

SD41100 $SN_JOG_REV_IS_ACTIVE, bit 0 = <value>

<value>

Meaning

0

Depending on the traversing mode, the revolutional feed rate is defined by the following

setting data:

• The indexing axis traverses as positioning axis:

SD43300 $SA_ASSIGN_FEED_PER_REV_SOURCE (revolutional feedrate for positioning ax-

es)

• The indexing axis traverses as geometry axis, on which a frame with rotation acts:

SD42600 $SC_JOG_FEED_PER_REV_SOURCE (revolutional feedrate in JOG)

1

The indexing axis is traversed with a rotational feedrate derived from the master spindle:

Corresponding machine data:

• MD32050 $MA_JOG_REV_VELO (revolutional feed rate for JOG mode)

• MD32040 $MA_JOG_REV_VELO_RAPID (revolutional feed rate for JOG with rapid traverse

override)

Further information

• Feedrates (Page 195)

• Manual traversing (Page 695)

• NC Programming Programming Manual

10.2.3

Traversing of indexing axes by PLC

Indexing axes can be traversed from the PLC user program.

• Competing positioning axes, see Section "Positioning axes (Page 271)"

• Asynchronous subprograms (ASUBs)

Further information:

Function Manual Basic Functions; Mode group, channel, program operation, reset response

See also

Homing (Page 31)

Axes and spindles

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Indexing axes

10.3 Commissioning

10.3

Commissioning

10.3.1

Machine data for indexing axes

Indexing axis

An axis is defined as indexing axis by assigning an indexing position table to this axis, using the

following axis-specific machine data:

MD30500 $MA_INDEX_AX_ASSIGN_POS_TAB = <value>

<Val-

Meaning

ue>

1

The axis is assigned indexing position table 1.

2

The axis is assigned indexing position table 2.

3

Equidistant indexing intervals (Page 331)

First indexing position for indexing axes with equidistant positions

For an indexing axis with equidistant positions, the absolute position of the first indexing

position is set using the following axes-specific machine data:

MD30503 $MA_INDEX_AX_OFFSET

Indexing position tables

In the indexing position tables, the indexing positions are saved in mm, inches or degrees.

Presently, two indexing position tables are available.

MD10910 $MN_INDEX_AX_POS_TAB_1 [ <n> ] (indexing position table 1)

MD10930 $MN_INDEX_AX_POS_TAB_2 [ <n> ] (indexing position table 2)

with <n> = 0 ... (maximum number - 1)

Multiple table assignment

Several axes can be assigned to an indexing position table.

Requirement: the axes are of the same type (linear axis, rotary axis, modulo 360° function)

General supplementary conditions

• The indexing positions must be listed in the indexing position table without gaps in an

ascending order.

• Indexing positions that follow one another must not be identical.

• The indexing positions must be specified in the basic coordinate system.

Axes and spindles

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Indexing axes

10.3 Commissioning

Additional secondary conditions for modulo rotary axes

• Permissible range: 0° ≤ indexing position < 360°

• If the indexing axis is at the last indexing position in the indexing position table, when

traversing to the next indexing position in the positive direction of rotation, the first indexing

position is approached.

• If the indexing axis is at the first indexing position in the indexing position table, when

traversing to the next indexing position in the negative direction of rotation, the last indexing

position is approached.

No. of indexing positions

A maximum of 60 indexing positions can be entered in an indexing position table. The actual

number of indexing positions that is used or the programmable number is defined using

machine data:

MD10900 $MN_INDEX_AX_LENGTH_POS_TAB_1 (number of indexing positions of indexing

position table 1)

MD10920 $MN_INDEX_AX_LENGTH_POS_TAB_2 (number of indexing positions of indexing

position table 2)

Note

Entries in the indexing positions table that exceed the parameterized number of indexing

positions are not considered.

System of units for indexing positions

The system of units of indexing positions is defined on an NC-specific basis:

MD10270 $MN_POS_TAB_SCALING_SYSTEM = <value>

<Val-

System of units

ue>

0

Metric

1

inch

Note

The machine data is only evaluated if the following applies: MD10260

$MN_CONVERT_SCALING_SYSTEM == 1

Displaying the actual indexing position

When traversing indexing axes, the machine data is used to define at which actual position the

display of the actual indexing position changes in the system variable

$AA_ACT_INDEX_AX_POS_NO:

Axes and spindles

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Indexing axes

10.3 Commissioning

MD10940 $MN_INDEX_AX_MODE, bit 0 = <value>

Bit

<Val-

Meaning

ue>

0

0

When traversing in the direction of ascending indexing positions, the displayed current

indexing position changes in the system variable $AA_ACT_INDEX_AX_POS_NO upon

reaching/overtraveling the "Exact stop fine" window (MD36010 $MA_STOP_LIM-

IT_FINE) of the next indexing position.

When traversing in the direction of descending indexing positions, the indexing posi-

tion display changes as soon as you exit the "Exact stop fine" window.

Linear axis

Modulo rotary axis

①

The traversing range of the indexing axis with indexing positions and "Exact

stop fine" window

②

Indexing position indicated in the system variable $AA_ACT_IN-

DEX_AX_POS_NO

1

The actual indexing position indicated in system variable $AA_ACT_IN-

DEX_AX_POS_NO changes when reaching/passing half the traversing distance to the

next indexing position in the traversing direction.

Linear axis

Modulo rotary axis

①

Traversing range of the indexing axis with indexing positions

②

Indexing position indicated in the system variable $AA_ACT_IN-

DEX_AX_POS_NO

Axes and spindles

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Indexing axes

10.3 Commissioning

Note

With the system variables $AA_ACT_INDEX_AX_POS_NO it is not possible to determine whether

an indexing position has been reached. To this end, one of the two following NC/PLC interface

signals must also be evaluated:

DB31, ... DBX76.6 (indexing position reached)

DB31, ... DBX60.7 (exact stop fine reached)

Example

Assumptions:

• MD10940 $MN_INDEX_AX_MODE, bit 0 == 1

• The axis is located in front of an indexing position outside the tolerance window "exact stop

fine" (DB31,

DBX60.7 == 0)

Although system variable $AA_ACT_INDEX_AX_POS_NO indicates indexing position 2, with the

"Traverse to next position" command, indexing position 3 is not approached, but first precisely

to indexing position 2. Only when the axis is precisely at (DB31,

DBX60.7 == 1) - or is located

after the displayed indexing position, using the "Traverse to next position" command, the next

indexing position is approached, in the example, indexing position 3. This means that the

indexing position is approached that is the closest in the traversing direction ! Under certain

circumstances, it is therefore necessary to issue the "traverse to next position" command twice

to move from the currently displayed indexing position to the next indexing position.

10.3.2

Machine data for equidistant indexing intervals

10.3.2.1

Features

Distance between indexes

The index distance is determined for equidistant index intervals according to the following

formula:

Numerator (MD30501 $MA_INDEX_AX_NUMERATOR)

Distance =

Denominator (MD30502 $MA_INDEX_AX_DENOMINATOR)

Axes and spindles

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331

Indexing axes

10.3 Commissioning

Linear axes

0'

0$B,1'(;B$;B2))6(7 VW GLVWDQFH IURP ]HUR SRLQW SRVLWLYH

'LVWDQFH VWDQGDUG IRU DOO LQGH[LQJ SRVLWLRQV VHH DERYH

0'

0$B,1'(;B$;B2))6(7 VW GLVWDQFH IURP ]HUR SRLQW QHJDWLYH

'LVWDQFH VWDQGDUG IRU DOO LQGH[LQJ SRVLWLRQV VHH DERYH

Modulo rotary axes

Numerator (MD30330 $MA_MODULO_RANGE)

Index =

Denominator (MD30502 $MA_INDEX_AX_DENOMINATOR)

MD30503 $MA_INDEX_AX_OFFSET

0¡˘

Spacing

Size of modulo range (MD30330 $MA_MODULO_RANGE)

Index =

Number of indexes in modulo range (MD30502 $MA_INDEX_AX_DENOMINATOR)

Axes and spindles

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Indexing axes

10.3 Commissioning

10.3.2.2

Hirth axis

Function

For a "Hirth axis", using a special gearing (Hirth gearing) the rotary axis is interlocked when

reaching an indexing position. In this case, a locking bolt or a gearwheel is engaged using a

linear axis. In order that the mechanical system of the machine is not damaged, the interlock can

only be engaged at an indexing position. For a Hirth axis, all of the indexing positions must have

the same the distance between one another (equidistant indexing positions).

Requirements

• The "Hirth axis" must be a rotary axis.

• The "Hirth axis" must be an indexing axis. See Section "Commissioning (Page 328)"

• The active measuring system of the indexing axis must be synchronized or referenced:

DB31, ... DBX60.4/.5 == 1 (referenced/synchronized, encoder 1/2)

Further information

Homing (Page 31)

Commissioning

Machine data

• MD30300 $MA_IS_ROT_AX = 1 (rotary axis)

• MD30505 $MA_HIRTH_IS_ACTIVE[ <axis> ] = 1 (indexing axis with Hirth gearing)

• MD30500 $MA_INDEX_AX_ASSIGN_POS_TAB[ <axis> ] = 3 (indexing axis with equidistant

indexing positions)

10.3.3

Axis-specific system variables

$AA_PROG_INDEX_AX_POS_NO

Function

The system variable includes the number of the indexing position programmed for the indexing

axis.

Syntax

$AA_PROG_INDEX_AX_POS_NO[<axis>]

Meaning

$AA_PROG_INDEX_AX_POS_NO

0

The axis is not an indexing axis, or presently the indexing axis is not traversing to an indexing

position

> 0

Number of programmed indexing position

Axes and spindles

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333

Indexing axes

10.4 Programming

$AA_ACT_INDEX_AX_POS_NO

Function

The system variable includes the number of the indexing position last reached by the indexing

axis, or indexing position that was passed by the indexing axis.

Syntax

$AA_ACT_INDEX_AX_POS_NO[<axis>]

Meaning

$AA_ACT_INDEX_AX_POS_NO

0

The axis is not an indexing axis.

> 0

Number of the last indexing position reached or passed

10.3.4

NC/PLC interface signals

Axis-specific interface signals

When stopping the indexing axis at an indexing position ± exact stop window fine (MD36010

$MA_STOP_LIMIT_FINE), then the axis-specific interface signal is set:

DB31, ... DBX76.6 = 1 (indexing axis in position)

10.4

Programming

Coded position

To allow indexing axes to be positioned from the NC part program, special instructions are

provided with which the indexing numbers (e.g. location numbers) are programmed instead of

axis positions in mm or degrees. The availability of a special instruction depends on the axis type

(linear or rotary axis):

Statement

Effect

Availability

CAC(i)

Traverse coded position in absolute terms

Linear axis, rotary axis

CACP(i)

Traverse coded position ain absolute terms in

Rotary axis

the positive direction

CACN(i)

Traverse coded position ain absolute terms in

Rotary axis

the negative direction

CDC(i)

Traverse coded position along the direct (short-

Rotary axis

est) path

CIC(i)

Traverse coded position incrementally

Linear axis, rotary axis

i:

Coded position (indexing position)

Value range of i:

0 ... 59; whole number (positive and negative values are possible

in CIC)

Axes and spindles

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Indexing axes

10.5 Supplementary conditions

System variables

Information on the indexing positions can be read via the following system variables:

• $AA_PROG_INDEX_AX_POS_NO

Number of the last programmed indexing position

• $AA_ACT_INDEX_AX_POS_NO

Number of the last overtraveled indexing position

The display depends on the setting in machine data MD10940 $MN_INDEX_AX_MODE.

• $AA_ACT_INDEX_AX_POS_NO

Number of the last indexing position reached or passed

Indexing positions

For axis type

Values

Description

Modulo rotary axis

1, ... n

n = number of indexing positions (Page 328)

Linear axis

0, 1, 2, 3, ... 59,

0

The actual position lies below the lowest indexing

60, 61

position

61

The actual position lies above the highest indexing

position

Equidistant indexing positions

For axis type

Values

Description

Modulo rotary axis

1 ... m

m = denominator (counter)

Linear axis

... -3, -2, -1, 0, 1,

2, 3, ...

10.5

Supplementary conditions

Indexing axes

Various channel and axis-specific NC/PLC interface signals

If, while an indexing axis is traversed, at least one of the following signals occurs, then the axis

stops immediately. The indexing positions are not taken into account.

• Channel-specific signals

- DB21, ... DBB4 == 0 (feedrate override)

- DB21, ... DBX6.2 == 1 (delete distance-to-go)

- DB21, ... DBX7.3 == 1 (NC Stop)

- DB21, ... DBX7.4 == 1 (NC Stop axes plus spindles)

- DB21, ... DBX7.7 == 1 (reset)

• Axis-specific signals

- DB31, ... DBX4.3 == 1 (feedrate stop)

Axes and spindles

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Indexing axes

10.6 Examples

10.6

Examples

10.6.1

Example 1: Rotary axis as indexing axis

Machine axes AX5 is a tool revolver, with 8 revolver locations (endlessly rotating rotary axis). The

distances between the revolver locations are constant (equidistant indexing positions).

Indexing

position

1

8

0¡˘

2

315¡˘

45¡˘

Axis position

7

270¡˘

90¡˘

3

225¡˘

135¡˘

180¡˘

6

4

5

Figure 10-1

Tool turret with 8 locations

Indexing position table 1

MD10910 $MN_INDEX_AX_POS_TAB_1[ 0 ] = 0

1st indexing position = 0°

MD10910 $MN_INDEX_AX_POS_TAB_1[ 1 ] = 45

2nd indexing position = 45°

MD10910 $MN_INDEX_AX_POS_TAB_1[ 2 ] = 90

3rd indexing position = 90°

MD10910 $MN_INDEX_AX_POS_TAB_1[ 3 ] = 135

4th indexing position = 135°

MD10910 $MN_INDEX_AX_POS_TAB_1[ 4 ] = 180

5th indexing position = 180°

MD10910 $MN_INDEX_AX_POS_TAB_1[ 5 ] = 225

6th indexing position = 225°

MD10910 $MN_INDEX_AX_POS_TAB_1[ 6 ] = 270

7th indexing position = 270°

MD10910 $MN_INDEX_AX_POS_TAB_1[ 7 ] = 315

8th indexing position = 315°

Length of the indexing position table (1)

MD10900 $MN_INDEX_AX_LENGTH_POS_TAB_1= 8

8 indexing positions in table 1

Defining machine axis AX5 as rotary modulo axis and indexing axis

MD30300 $MA_IS_ROT_AX[ AX5 ] = 1

Rotary axis

MD30310 $MA_ ROT_IS_MODULO [AX5] = 1

Modulo rotary axis

MD30500 $MA_INDEX_AX_ASSIGN_POS_TAB [AX5] = 1

Indexing axis, indexing position table 1

Axes and spindles

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339

Indexing axes

10.6 Examples

10.6.2

Example 2: Indexing axis as linear axis

Machine axis AX6 is a workholder with 10 locations. The distances between the 10 locations are

different. The first location is at position -100 mm. Machine axis is AX6.

,QGH[LQJ SRVLWLRQ

$[LV SRVLWLRQ >PP@

Figure 10-2

Indexing positions for a workholder

Indexing position table 2

MD10930 $MN_INDEX_AX_POS_TAB_2[ 0 ] = -100

1st indexing position = -100 mm

MD10930 $MN_INDEX_AX_POS_TAB_2[ 1 ] = 0

2nd indexing position = 0 mm

MD10930 $MN_INDEX_AX_POS_TAB_2[ 2 ] = 100

3rd indexing position = 100 mm

MD10930 $MN_INDEX_AX_POS_TAB_2[ 3 ] = 200

4th indexing position = 200 mm

MD10930 $MN_INDEX_AX_POS_TAB_2[ 4 ] = 300

5th indexing position = 300 mm

MD10930 $MN_INDEX_AX_POS_TAB_2[ 5 ] = 500

6th indexing position = 500 mm

MD10930 $MN_INDEX_AX_POS_TAB_2[ 6 ] = 700

7th indexing position = 700 mm

MD10930 $MN_INDEX_AX_POS_TAB_2[ 7 ] = 900

8th indexing position = 900 mm

MD10930 $MN_INDEX_AX_POS_TAB_2[ 8 ] = 1250

9th indexing position = 1250 mm

MD10930 $MN_INDEX_AX_POS_TAB_2[ 9 ] = 1650

10. Indexing position = 1650 mm

Length of the indexing position table (1)

MD10920 $MN_INDEX_AX_LENGTH_POS_TAB_2 = 10

10 indexing positions in table 2

Defining machine axis AX5 as indexing axis

MD30500 $MA_INDEX_AX_ASSIGN_POS_TAB [AX6] = 2

Indexing axis, indexing position table 2

10.6.3

Example 3: Rotary modulo axis as equidistant indexing axis

Machine axis AX4 is rotary modulo axis with equidistant indexing. Indexing starts at 5°. The

difference between the indexing positions is 20°.

The following indexing positions are obtained:

5, 25, 45, 65, 85, 105, 125, 145, 165, 185, 205, 225, 245, 265, 285, 305, 325, 245 [Degrees]

Axes and spindles

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Indexing axes

10.6 Examples

Indexing data

MD30501 $MA_INDEX_AX_NUMERATOR[ AX4 ] ⇒

This value is ignored for rotary modulo

axes, and MD30330 $MA_MODU-

MD30330 $MA_MODULO_RANGE[ AX4 ] = 360.0

LO_RANGE (default value: 360°) is used

instead.

MD30502 $MA_INDEX_AX_DENOMINATOR[ AX4 ] = 18

Number of indexing positions = 360° /

20° = 18

MD30503 $MA_INDEX_AX_OFFSET[ AX4 ] = 5.0

First indexing position = 5.0°

MD30505 $MA_HIRTH_IS_ACTIVE[ AX4 ] = 0

No Hirth gearing

Defining machine axis AX4 as rotary modulo axis and equidistant indexing axis

MD30300 $MA_IS_ROT_AX[ AX4 ] = 1

Rotary axis

MD30310 $MA_ ROT_IS_MODULO[ AX4 ] = 1

Modulo function active

MD30500 $MA_INDEX_AX_ASSIGN_POS_TAB[ AX4 ] = 3

Equidistant indexing axis

10.6.4

Example 4: Rotary axes as equidistant indexing axis with restricted traversing

range

Machine axis AX4 is a rotary axis with equidistant indexing. The equidistant indexing positions

are every 20°, starting at 100°. Positions less than 100° and greater than 260° should not be

approached.

The following indexing positions are obtained:

100, 120, 140, 160, 180, 200, 220, 240, 260 [degrees]

Indexing data

MD30501 $MA_INDEX_AX_NUMERATOR[ AX4 ] = 360.0

Numerator = 360°

MD30502 $MA_INDEX_AX_DENOMINATOR[ AX4 ] = 18

Number of indexing positions = 360° /

20° = 18

MD30503 $MA_INDEX_AX_OFFSET[ AX4 ] = 100.0

First indexing position = 100.0°

MD30505 $MA_HIRTH_IS_ACTIVE[ AX4 ] = 0

No Hirth gearing

Defining machine axis AX4 as rotary modulo axis and equidistant indexing axis

MD30300 $MA_IS_ROT_AX[ AX4 ] = 1

Rotary axis

MD30310 $MA_ ROT_IS_MODULO[ AX4 ] = 1

Modulo function active

MD30500 $MA_INDEX_AX_ASSIGN_POS_TAB[ AX4 ] = 3

Equidistant indexing axis

MD36100 $MA_POS_LIMIT_MINUS[ AX4 ] = 100.0

1st software limit switch minus = 100.0°

MD36110 $MA_POS_LIMIT_PLUS[ AX4 ] = 260.0

1st software limit switch plus = 260.0°

10.6.5

Example 5: Linear axis as equidistant indexing axis

Machine axis AX4 is a linear axis with equidistant indexing. The equidistant indexing positions

are every 10 mm, starting at -200 mm.

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Indexing axes

10.6 Examples

The following indexing positions are obtained:

-200, -190, -180, ... 180, 190, 200 [mm]

Indexing data

MD30501 $MA_INDEX_AX_NUMERATOR[ AX4 ] = 10.0

Numerator = 10

MD30502 $MA_INDEX_AX_DENOMINATOR[ AX4 ] = 1

Denominator = 1

MD30503 $MA_INDEX_AX_OFFSET[ AX4 ] = -200.0

First indexing position = -200.0°

MD30505 $MA_HIRTH_IS_ACTIVE[ AX4 ] = 0

No Hirth gearing

Defining machine axis AX4 as linear axis and equidistant indexing axis

MD30300 $MA_IS_ROT_AX[ AX4 ] = 0

Linear axis

MD30310 $MA_ ROT_IS_MODULO[ AX4 ] = 0

Modulo function is not active

MD30500 $MA_INDEX_AX_ASSIGN_POS_TAB[ AX4 ] = 3

Equidistant indexing axis

MD36100 $MA_POS_LIMIT_MINUS[ AX4 ] = -200.0

1st software limit switch minus = -200.0

mm

MD36110 $MA_POS_LIMIT_PLUS[ AX4 ] = 200.0

1st software limit switch plus = 200.0

mm

10.6.6

Example 6: "Hirth axis"

Machine axis AX4 is a "Hirth axis" (rotary modulo axis with equidistant indexing and Hirth

gearing). The equidistant indexing positions are every 1°, starting at 0°.

Indexing data

MD30501 $MA_INDEX_AX_NUMERATOR[ AX4 ] ⇒

This value is ignored for rotary modulo

axes, and MD30330 $MA_MODU-

MD30330 $MA_MODULO_RANGE[ AX4 ] = 360.0

LO_RANGE (default value: 360°) is used

instead.

MD30502 $MA_INDEX_AX_DENOMINATOR[ AX4 ] = 360

Number of indexing positions = 360° / 1°

= 360

MD30503 $MA_INDEX_AX_OFFSET[ AX4 ] = 0.0

First indexing position = 0.0°

MD30505 $MA_HIRTH_IS_ACTIVE[ AX4 ] = 1

Hirth gearing

Defining machine axis AX4 as linear axis and equidistant indexing axis

MD30300 $MA_IS_ROT_AX[ AX4 ] = 1

Rotary axis

MD30310 $MA_ ROT_IS_MODULO[ AX4 ] = 1

Modulo function active

MD30500 $MA_INDEX_AX_ASSIGN_POS_TAB[ AX4 ] = 3

Equidistant indexing axis

MD36100 $MA_POS_LIMIT_MINUS[ AX4 ] = -200.0

1st software limit switch minus = -200.0

mm

MD36110 $MA_POS_LIMIT_PLUS[ AX4 ] = 200.0

1st software limit switch plus = 200.0

mm

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Indexing axes

10.7 Data lists

10.7

Data lists

10.7.1

Machine data

10.7.1.1

General machine data

Number

Identifier: $MN_

Description

10260

CONVERT_SCALING_SYSTEM

Basic system switchover active

10270

POS_TAB_SCALING_SYSTEM

System of measurement of position tables

10900

INDEX_AX_LENGTH_POS_TAB_1

Number of positions for indexing axis table 1

10910

INDEX_AX_POS_TAB_1[n]

Indexing position table 1

10920

INDEX_AX_LENGTH_POS_TAB_2

Number of positions for indexing axis table 2

10930

INDEX_AX_POS_TAB_2[n]

Indexing position table 2

10940

INDEX_AX_MODE

Options for indexing positions

10.7.1.2

Axis/spindlespecific machine data

Number

Identifier: $MA_

Description

30300

IS_ROT_AX

Rotary axis

30310

ROT_IS_MODULO

Modulo conversion for rotary axis

30320

DISPLAY_IS_MODULO

Position display is modulo 360°

30500

INDEX_AX_ASSIGN_POS_TAB

Axis is indexing axis

30501

INDEX_AX_NUMERATOR

Numerator for indexing axes with equidistant positions

30502

INDEX_AX_DENOMINATOR

Denominator for indexing axes with equidistant posi-

tions

30503

INDEX_AX_OFFSET

Indexing position for indexing axes with equidistant po-

sitions

30505

HIRTH_IS_ACTIVE

Hirth tooth system is active

10.7.2

Setting data

10.7.2.1

General setting data

Number

Identifier: $SN_

Description

41050

JOG_CONT_MODE_LEVELTRIGGRD

JOG continuous in inching mode

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Indexing axes

10.7 Data lists

10.7.3

System variables

Identifier

Description

$AA_ACT_INDEX_AX_POS_NO[axis]

Number of last indexing position reached or overtraveled

$AA_PROG_INDEX_AX_POS_NO[axis]

Number of programmed indexing position

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11

11.1

Brief description

For gantry machines, each of various machine elements, such as the gantry and the transverse

beams, are moved by several axes that operate in parallel. The axes that together move a

machine part, are designated as gantry axes or gantry grouping. Because of the mechanical

structure, the gantry axes are rigidly connected with each other and so must always be traversed

synchronously by the control.

=

=

=

<

=

JDQWU\ JURXSLQJ &URVVEHDPV

=

;

;

<

;

;

JDQWU\ JURXSLQJ *DQWU\

;

Figure 11-1

Example: Gantry-type milling machine with gantry and transverse beams

Guide axis

The guide axis of the gantry grouping is the axis that represents the gantry grouping. Only this

axis is programmed to perform the traversing movements of the gantry grouping.

Synchronous axes

The synchronous axes of the gantry grouping are the axes that because of their coupling with

the guide axis are also automatically traversed by the control. A guide axis can be assigned any

number of synchronous axes.

Synchronization difference

The synchronous operation difference is the deviation of the axial actual value of a synchronous

axis from its ideal position referred to the actual value of the guide axis. The control continually

monitors the synchronous operation difference. A message is displayed if the alarm limit is

exceeded. The complete gantry grouping is stopped when the alarm limit is exceeded. The limit

values can be parameterized as machine data.

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Gantry axes

11.2 "Gantry axes" function

11.2

"Gantry axes" function

11.2.1

Definition of a gantry grouping

Definition

The axes of a gantry grouping are specified via the following axial machine data:

MD37100 $MA_GANTRY_AXIS_TYPE[AX1] = xy

x

Tens decimal place: Type of gantry axis (guide or synchronous axis)

y

Ones decimal place: ID of the gantry grouping

A maximum of eight gantry groupings (gantry grouping ID: 1 - 8) can be defined. The gantry

grouping ID must be unique in all channels or in all NCUs in accordance with the assigned axis.

In principle, a gantry grouping can be assigned any number of synchronous axes.

Example

Definition of a gantry grouping with ID=1, guide axis AX1 and synchronous axis AX2

• MD37100 $MA_GANTRY_AXIS_TYPE[AX1] = 01 (guide axis)

• MD37100 $MA_GANTRY_AXIS_TYPE[AX2] = 11 (synchronous axis)

Supplementary conditions

The following supplementary conditions apply to a gantry grouping:

• A gantry grouping must not contain a spindle.

• A synchronous axis must not be a concurrent POS axis.

• A synchronous axis must not belong to a transformation.

• A synchronous axis must not be a following axis of another axis coupling.

• A synchronous axis must not be a guide axis of another axis coupling.

• All axes of a gantry grouping must be of the same axis type, linear or rotary: MD30300

$MA_IS_ROT_AX (rotary axis/spindle)

Note

Drive optimization

At a SINAMICS S120 drive unit, a maximum of three drives can be optimized or measured at

the same time (speed controller optimization / function generator). Therefore, for a coupling

with more than three coupled drives at the same time, we recommend that these are

distributed over several drive units.

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Gantry axes

11.2 "Gantry axes" function

11.2.2

Monitoring the synchronism difference

Limit values for monitoring

2 limit values can be specified for the synchronism difference.

Gantry warning limit

The gantry warning limit is set using the following machine data:

MD37110 $MA_GANTRY_POS_TOL_WARNING (gantry warning limit)

The "Alarm limit exceeded" message is displayed if the synchronism difference exceeds the

gantry warning limit. In addition, the NC/PLC-interface signal is set:

DB31, ... DBX101.3 = 1 (gantry warning limit exceeded)

After the alarm limit has been fallen below, the message and interface signal are automatically

reset.

Note

Gantry warning limit

If the "Alarm limit exceeded" message is not to be displayed, then a value of 0 should be entered

into MD37110.

Gantry trip limit

The gantry trip limit is set using the following machine data:

• for the synchronized gantry grouping:

MD37120 $MA_GANTRY_POS_TOL_ERROR

• for the non-synchronized gantry grouping:

MD37130 $MA_GANTRY_POS_TOL_REF

Alarm 10653 "Error limit exceeded" is displayed if the synchronism difference exceeds the gantry

trip limit. In addition, the NC/PLC-interface signal is set:

DB31, ... DBX101.2 = 1 (gantry trip limit exceeded)

Gantry trip limit:

Synchronous grouping: MD37120 $MA_GANTRY_POS_TOL_ERROR

Non-synchronous grouping: MD37130 $MA_GANTRY_POS_TOL_REF

Gantry warning limit:

MD37110 $MA_GANTRY_POS_TOL_WARNING

The alarm is also displayed if the gantry grouping is jammed (no controller enable, gantry

grouping in the "Hold" state).

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Gantry axes

11.2 "Gantry axes" function

11.2.5

Control dynamics

Use case

From the user perspective, a gantry grouping is exclusively traversed via the leading axis. The NC

generates the setpoints of the synchronous axes directly from the setpoints of the leading axis

in time synchronism and outputs these to them. To minimize the synchronous operation

differences, the control system dynamics of all axes of a gantry grouping must be set identical

(see Section "Start-up of gantry axes (Page 360)").

Note

Identical control dynamics must be set for all axes of a gantry grouping.

Disturbance characteristic

If faults occur, which cause an axis of the gantry to be stopped, then the complete gantry

grouping is always stopped.

11.2.6

Opening the gantry grouping

Description

The axis coupling within a gantry grouping can be opened (dissolved) using the following

machine data:

MD37140 $MA_GANTRY_BREAK_UP = 1 (invalidate gantry grouping)

CAUTION

No synchronous operation

If the gantry axes remain mechanically coupled, there is a risk of damage to the machine when

the leading or synchronous axes are traversed in this operating state!

When the setting becomes active, the axes of the gantry grouping can be individually traversed

in the JOG, AUTOMATIC and MDA modes.

The monitoring functions of the synchronism difference and/or the alarm and trip limits are not

active.

The NC/PLC interface signal "Gantry grouping is synchronized" is reset:

DB31, ... DBX101.5 = 0

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Gantry axes

11.3 Referencing and synchronization of gantry axes

Start referencing operation

Channel-specific

Axis-specific

from part program (with

(with IS "Activate referencing" = 1 and

(with IS "Traversing key +/-" = 1 of

G74 and axis address of

"Active machine function REF" = 1)

leading axis and "Active machine

leading axis)

function REF" = 1)

Section 1 Referencing of leading

Start "Referencing of

axis

gantry axes

Leading axis approaches ref. point; synchro-

nized axis traverses in synchronism

to PLC

IS "Referenced/synchronized" = 1 for

Reference point reached

leading axis

(Internal

Section 2

start)

Referencing of synchronized axis (axes)

Synchronized axis approaches reference

point; leading axis traverses in synchronism

to PLC

IS "Referenced/synchronized" = 1 for

Reference point reached

synchronized axis

j

Next synchro-

nized axis

n

Section 3

Synchronization

Message: "Wait

process

for synchronization

Comparison of actual positions of

start"

leading and synchronized axes

IS "Gantry synchronization ready

Deviation

j

to start¡- = 1

>

MD37110

$MA_GANTRY_POS_TOL_WARNING?

Servicing

n

(Internal start)

All gantry axes traverse in the decoupled state in

gantry synchronized position (MD34100

Operator starts gantry

$MA_REFP_SET_POS of the leading axis). With

synchronization process

absolute encoders and distance-coded encoders,

(External start)

the leading axis will traverse (set via MD34330

$MA_REFP_STOP_AT_ABS_MARKER)

IS "Start gantry synchronization" = 1

the current actual position of the leading axis or the

reference point.

Message:

to PLC

All gantry axes have reached

"Synchronization

synchronized position

in progress"

to PLC

Forced coupling between gantry

IS "Gantry grouping is

axes is reactivated

synchronized" = 1

End

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Gantry axes

11.3 Referencing and synchronization of gantry axes

Selecting the reference point

To ensure that the shortest possible paths are traversed when the gantry axes are referenced, the

reference point values from leading and synchronous axes should be the same in the machine

data:

MD34100 $MA_REFP_SET_POS (reference point value/destination point for distancecoded

system)

Allowance for deviations in distance between the zero mark and the reference point must be

made for specific axes via the machine data:

MD34080 $MA_REFP_MOVE_DIST (reference point distance)

MD34090 $MA_REFP_MOVE_DIST_CORR (reference point offset/absolute offset)

Referencing direction selection

The zero mark search direction of the synchronous axis can be defined via the machine data:

MD37150 $MA_GANTRY_FUNCTION_MASK, Bit 1

Bit

Value

Meaning

1

0

Zero mark search direction of the synchronous axis analog to machine data:

MD34010 $MA_REFP_CAM_DIR_IS_MINUS

1

Zero mark search direction of the synchronous axis the same as the leading axis

During referencing, the reference point value of the leading axis is specified as the target

position for all axes in the grouping for the synchronization compensatory motion. This position

is then approached without axis coupling. The absolute encoders and distanced-coded encoders

of the leading axis will be set to the current actual position of the leading axis or to the reference

point by the following machine data:

MD34330 $MA_REFP_STOP_AT_ABS_MARKER (Distancecoded linear measuring system

without destination point)

If only one reference cam is used for the leading and synchronous axes, then this must be taken

into account in the PLC user program.

11.3.2

Automatic synchronization

Automatic synchronization can take place:

• in the referencing mode (see Section "Introduction (Page 350)")

• in other modes, as described below:

If a gantry grouping is switched to follow-up mode, monitoring of the actual values between the

leading and synchronized axes is disabled. The grouping is no longer synchronized as a result.

Independent of axes positions, the following interface signal will be set to 0 (from leading axis)

DB31, ... DBX101.5 (gantry grouping is synchronous)

If the gantry grouping is switched from follow-up mode to position control mode, axis

synchronism is automatically restored provided the actual-value monitor does not detect a

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11.3 Referencing and synchronization of gantry axes

Activation of axis compensations

Compensation functions can be activated for both the leading axis and the synchronized axes.

Compensation values are applied separately for each individual gantry axis. These values must

therefore be defined and entered for the leading axis and the synchronized axes during start-up.

The compensations do not become operative internally in the control until the axis is referenced

or the gantry grouping synchronized. The following applies:

Compensation type

Takes effect when

PLC interface signal

Backlash compensation

Axis is referenced

"Referenced/Synchronized"

LEC

Axis is referenced

"Referenced/Synchronized"

Sag compensation

Gantry grouping is synchron-

"Gantry grouping is synchronized"

ized

Temperature compensation

Gantry grouping is synchron-

"Gantry grouping is synchronized"

ized

If a movement by the synchronized axis (axes) is caused by an active compensation, a travel

command is displayed for the synchronized axis (axes) independently of the leading axis.

Monitoring functions effective

Analogous to normal NC axes, the following monitoring functions do not take effect for gantry

axes until the reference point is reached (IS "Referenced/Synchronized"):

• Working area limits

• Software limit switch

• Protection zones

The axial machine data values are used as monitoring limit values for the synchronized axes as

well.

Multi-channel block search

The cross-channel block search in Program Test mode (SERUPRO "Search Run by Program test")

can be used to simulate the traversal of gantry axis groupings.

Note

For further information on the multichannel block search SERUPRO, please see:

Further information

Function Manual Basic Functions; Mode group, channel, program operation, program test

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Gantry axes

11.6 PLC interface signals for gantry axes

MD30455 $MA_MISC_FUNCTION_MASK, bit 9 = <value>

<Value>

Meaning

0

When a fault occurs that triggers the pulse suppression (e.g. measuring-circuit fault), the

pulses in all other axes of the gantry grouping will also be suppressed.

Result: Coast down of all axes of the gantry grouping.

1

When a fault occurs that triggers the pulse suppression (e.g. measuring-circuit fault), the

pulses for only this axis will be suppressed. The other axes of the gantry grouping will be

stopped. The pulses for these axes are also then suppressed. To ensure that the pulses these

axes are not suppressed in advance, especially for axes to be held at the standstill position

(vertical axes), the following drive parameters must be taken into account:

• p1135[0...n] OFF3 ramp-down time

• p1217 holding brake application time

• p1227 zero speed detection monitoring time

• p1228 pulse suppression, delay time

For a detailed description of drive parameters, refer to:

Further information

SINAMICS S120/S150 List Manual

11.6

PLC interface signals for gantry axes

Special IS for gantry axes

The special NC/PLC interface signals of the coupled gantry axes are taken via the axial NC/PLC

interface of the leading or synchronized axes. The table below shows all special gantry NC/PLC

interface signals along with their codes and indicates whether the IS is evaluated on the leading

axis or the synchronized axis.

NC/PLC interface signal

Direction of transfer

DB31, ...

Leading axis

Synchronous axis

DBX...

Start gantry synchronization

PLC → NC

29.4

X

No automatic synchronization

PLC → NC

29.5

X

Gantry axis

NC → PLC

101.7

1

1

Gantry leading axis

NC → PLC

101.6

1

0

Gantry grouping is synchronized

NC → PLC

101.5

X

Gantry synchronization ready to

NC → PLC

101.4

X

start

Gantry warning limit exceeded

NC → PLC

101.3

X

Gantry trip limit exceeded

NC → PLC

101.2

X

Effect of axial interface signals on gantry axes

a) Axial interface signals from the PLC to the axis (PLC → NC)

The axial interface signals from the PLC to the axis are always referred to all gantry axes in the

grouping. In this case, all gantry axes (leading and synchronized axis) have equal priority.

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