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KEB COMBIVERT F5-A,-E,-H 4.0. APPLICATION MANUAL (2008) - page 18

Positioning and Synchronous Control

Sy.43: Control word long

Sy.50: Control word low

Bit

Meaning

Value

Explanation

Start Positio-

0

Without function for positioning

10

ning

1024

Switch from not activated to activated starts positioning

Starting a new positioning is only possible if bit 10 has temporarily been set to 0.

● by writing a new target position to parameter PS.24 or by set changeover

To start a positioning by writing a new target position or by set changeover, the following adjustments

must be made in PS.00:

PS.00: Posi / synchronous mode

Bit

Meaning

Value

Explanation

Start positioning

0: off

For "start positioning by set change = on", every set change automatical-

9

via set change

512: on

ly generates a "start positioning" command.

0: off

For "start positioning PS.24 = on", a "start positioning" command is ge-

Start positioning

12

nerated each time parameter PS.24 is written to (independent of the in-

PS.24

4096: on

dex).

To perform a positioning, the inputs wired as limit switches (inputs with functions "forward" and "backward")

must be active. If the hardware limit switches are not to be used, the protection functions in Pn.07 "Proh. rota-

tion stopping mode" must be deactivated (value 6: function switched off).

If the target position can still be changed during a running positioning is determined by PS.00 bit 3

PS.00: Posi / synchronous mode

Bit

Meaning

Value

Explanation

After starting a positioning, the target position that was valid at the time of

0: off

the "start positioning" command is approached.

For a new "start positioning" command during the acceleration or constant

running phase of a running positioning (status "122: positioning active"),

Termination due

the new target is adopted and approached if it is accessible with the de-

3

to new start po-

fined acceleration / deceleration /jolt times. (For the processing of inac-

sitioning

8: on

cessible positions, see chapter 7.12.4.15) For a sequential positioning, the

running positioning sequence is aborted. With the new "start positioning"

command, a new positioning sequence is started with the index program-

med in PS.28 "start index new profile".

If the drive leaves the vector controlled operation (first "start positioning" after activation of the positioning

mode), or if during an active positioning a new "start positioning" command is given, the new target is possibly

inaccessible with the adjusted ramp and jolt times.

Parameter ru.84 "accessible relative position" shows the distance that the target must have to the actual posi-

tion ru.54 at the time of the "start positioning" pulse to be accessible with the programmed ramp and S-curve

times.

Page7.12 - 64

Positioning and Synchronous Control

Example:

Start of the deceleration

Start

to target approach

At the "start positioning command", ru.84

positioning

indicates that the target must be at least

ru.84

200000 increments away from the current

actual position to be accessible with the pro-

grammed ramps.

The target is further away and the drive po-

sitions to the target.

The deceleration phase starts when the

amount of ru.84 ahead of the target is re-

ru.84

ached.

If the target is inaccessible with the ramps from the oP-parameters, the ramp times can be changes online in

the event of a new "start positioning" pulse. For that purpose, there is the parameter PS.32 "limit acc/dec red-

ucing %".

Note: For the case of a start from the vector controlled operation, the online adaption is not active. In parameter

PS.32, a factor between 25 and 100% can be set. 25% means that the ramp and S-curve times may be reduced

to maximally 25% and increased by up to a factor of 4. The value 33% in PS.32 would correspondingly allow a

change of between 33% and a factor of 3 of the values set in the OP-parameters.

ru.54 "Actual position" + ru.84 "ac-

New „Start positioning“

cessible rel. position" is greater than

the target.

I.e., the target would be inaccessible

without ramp decrease.

7

In this example, the same values are

set for the

deceleration ramps as for the acce-

leration ramp.

With PS.32, the ramp times are shor-

tened so that the target is reached in

ru.84

a shorter distance than ru.84

The new "start positioning" command must occur within the positioning, in the acceleration or constant running

phase. In the deceleration phase to the final target approach, the new starting pulse leads to the status "position

inaccessible".

If the new starting pulse is received in the correct phase, but the target is inaccessible despite ramp adjustment

, the drive enters the state "position inaccessible" with the default ramp/jolt times.

The parameter PS.32 is similar to the parameter PS.44 "limit acc/dec corr. %" in its mode of action. PS.44,

however, works only for ramp changes necessitated by flying referencing with adjustment. PS.32, on the other

hand, is responsible for adjustments based on new target settings.

Furthermore, the ramp can also be changed during the acceleration phase by PS.32 if the new target setting

makes it necessary.

With the parameter PS.53 "distance for no abort", unwanted "start positioning" commands can be masked.

Since the last "start positioning" command, the drive must have travelled a greater distance than PS.53 so that

a new starting command is accepted during a running positioning.

Page7.12 - 65

Positioning and Synchronous Control

Example:

At the "start positioning command", ru.84 indi-

cates that the target must be at least 200000

increments away from the current actual po-

sition to be accessible with the programmed

ramps.

The target is further away and the drive posi-

PS.53: Distance

for no abort

tions to the target.

The deceleration phase starts when the

amount of ru.84 ahead of the target is rea-

ched.

New „Start Positioning“

commands are not accepted

in this range

First „Start positioning“

Target reached

Page7.12 - 66

Positioning and Synchronous Control

7.12.4.15

Posi mode / not reachable positions

An "inaccessible position" is a target position that cannot be reached with the programmed acceleration / de-

celeration and jolt times.

This can occur in the following circumstances:

● Transition from vector controlled to position controlled operation due to the first "start positioning" after

activation of the positioning mode

● Change of the target position during a running positioning by a new "start positioning" signal

● during sequential positioning, when no stop is scheduled at the target

● due to a change in the actual and set point positions by flying referencing with adjustment

● if the drive is running at the time of the "start positioning" command and a rotation change is required for

the positioning

I.e., every time the drive is running at the time of the "start positioning" command, inaccessible positions can

occur.

Also, if a new "start positioning" pulse is given during the deceleration phase to the original target, and the S-

curves are switched off, the message "inaccessible position" is generated because an adjustment during the

final approach to target is only executed during the lower S-curve.

Position not reachable, because new

Position not reachable, because new target is nearby

„Start positioning“ during deceleration

ramp

7

Page7.12 - 67

Positioning and Synchronous Control

The response to this status is selectable via PS.00:

PS.00: Posi / synchronous mode

Bit

Meaning

Value

Explanation

The drive stops with the adjusted ramps. Status ru.00 shows "123:

position inaccessible". This status is reset only by deactivation of the

0: stop

positioning module. While this status is active, no new "start positio-

ning" commands are accepted.

The drive stops with the adjusted ramps In status ru.00, "123: position

64: stop

inaccessible" is shown during the deceleration ramp. After reaching

+ new

standstill, a new positioning to the target position starts automatically

attempt

If position not

(status changes to "122: positioning active").

6 / 7

reachable

This function is required only for sequential positioning: The target

positions of the individual positioning steps are traversed, even if the

128: new

target speed set in PS.25 cannot be reached. This permits checking

attempt

where the positioning sequence has to be changed or adjusted so that

target position and target speed can be reached. This should facilitate

the parametrisation of the index speeds / positions.

192: reser-

reserved

ved

The behaviour of the drive is determined by PS.00 bit 6 / 7 (explana-

0: off

tion see above)

If the new target is inaccessible, the "start positioning" command

Ignore position,

8

is ignored. With a digital output, the ignoring of the position can be

if not reachable

256: on

displayed. The positioning module remains active, new "start positio-

ning" commands are executed. The digital output can be reset only by

deactivation of the positioning module.

Stop

Stop + new test

Ignore not reachable target

Ignore new

target

Target not

reachable

Start posi-

tioning

Page7.12 - 68

Positioning and Synchronous Control

7.12.4.16

Posi mode / stop positioning

A deactivation of the input occupied with the function "positioning /synchronous activation" concludes the po-

sitioning mode. A running positioning that was aborted by the deactivation cannot be resumed after switching

the input back on.

If the input remains activated, an active positioning can be interrupted by quick stopping, deactivation of the

control release, triggering of the "power off" function or occurence of an error (e.g.,: E.OC, E.OP, etc.).

After the drive is "ready for positioning" again, an interrupted positioning must be restarted with a "start posi-

tioning" command.

With parameter PS.00, one can select how the drive should behave after an error occurs (i.e., after interruption

of an active positioning):

PS.00: Posi / synchronous mode

Bit

Meaning

Value

Explanation

0: Starting

The target position (PS.24) from the starting index block is approa-

index from

Behaviour after

ched with the first "start positioning" after the interruption.

5

PS.28

error

32: last tar-

The target position that was positioned to when the interruption

get position

occurred will be approached with the first "start positioning".

Note: a sequential positioning is aborted only if the error (the interruption) occurred during an active positioning.

If the drive is stopped at the target (even if it is only an intermediate target of the sequential positioning), swit-

ching off the control release, for example, does not lead to a termination of the sequential positioning.

An active positioning can also be interrupted by setting bit 11 in control word Sy.43 or Sy.50

(field 2048: "activate interruption").

In contrast to a termination due to abnormal stopping, the ramps from the OP-parameters are used and started

7

S-curves are not interrupted in a termination initiated by the control word. The modulation remains on.

If bit 11 "termination" has again been deactivated in the control word, there are two possibililties for the drive

to continue:

PS.52: Automatically execution positioning after STOP

Value

Explanation

The drive waits for a new "start positioning" command. The current position setpoint PS.24 is

0: off

inherited for the new positioning.

The drive automatically starts a new positioning on the target that was approached at the

1: on

time of the termination by the control word. A change of the position setpoint PS.24 while the

"termination"-bit is set is ignored.

Page7.12 - 69

Positioning and Synchronous Control

7.12.4.19

Target window

In parameter PS.30 "target window", the target window range is given. The target window has been reached if

the actual position is in the range of +/- PS.30 / 2 around the target position.

PS.30 Target window = 1000

4000

5000

6000

ru.61 Target position = 5000

7.12.4.20

Position scan

With parameter PS.37 "position scan index input selection", or via the digital Input function (di.24...di.35) "scan

position", an input can be defined for scanning the actual position (ru.54) with the positive edge.

The position scan happens only in status "positioning active". The scanned actual position value (ru.54) is dis-

played in parameter ru.71 "teach/ scan position". Each further edge overwrites the old scan position.

Dependent on the scanned position, a digital output can be set. The switching condition "75: amount current

position-scan position > level" must be chosen for this.

The output function "switching condition 0" is reset

by:

● Setting of a new target position

● Reaching of the target position

7

Switching level 0

● The target position is not reachable

● Quitting the positioning mode

Note:

Switching condi-

As long as the switching condition remains set, the

tions 0

teach-function

(see chapter

7.12.4.21) cannot be

Position scan

used.

Positioning active

Start positioning

Page7.12 - 71

Positioning and Synchronous Control

7.12.4.21

Teach function

With parameter PS.37 "teach index input selection", or via the digital Input function (di.24...di.35) "store position

(teach)", an input can be defined for scanning the actual position (ru.54) with the positive edge.

The scanned value is displayed in parameter ru.71 "teach / scan position" and stored in PS.24 as the target

position. Parameter PS.35 "teach mode" determines which positioning block (which index) the target position

is stored in.

PS.35: Teach mode

Value

Explanation

The current position is written to the positioning block pointed to by para-

0: Write index PS.23

meter PS.23 "index selection".

The current position is written to the positioning block pointed to by para-

1: Write index PS.23 incr.

meter PS.23 "index selection" and subsequently, PS.23 is increased by 1

(limited to maximum index 31).

The current position is written to the positioning block pointed to by para-

2: Write index PS.28

meter PS.28 "start index new profile". Since PS.28 is set-programmable,

positions can be linked with sets this way.

Example: Teaching of target position

An undercarriage shall "learn" the position values belonging to a storage location (the position value shall be

taught). In inching mode, the drive is brought to the position that is to be used later as the target of the positio-

ning (i.e., the storage location on a shelf). The drive is in vector controlled mode, i.e., the input activating the

positioning mode is not set.

Since several storage locations are to be taught consecutively, the setting is PS.35 "teach mode" = 1. If the

correct position is reached, it is registered as the target position by the teach-pulse. After that, the next storage

location is approached.

The following figure illustrates the example:

With the digital inputs, 3 constants are selected:

PS.24 Index 2

● higher speed for coarse target approach constant

PS.24 Index 1

1 = 300 rpm

● inching mode for exact target approach

PS.24 Index 0

Fixed value 2 = 50 rpm

Fixed value 3 = -50 rpm

The desired position is approached in vector controlled

operation.

With a teach-pulse (positive edge of the chosen digital in-

put), the current actual position is registered as the target

position of a positioning block.

The process starts with the index currently selected in

PS.23. Thereafter, the index is increased after every tar-

get position acquisition.

Page7.12 - 72

Positioning and Synchronous Control

7.12.4.22

Functions and displays for the positioning mode

This chapter provides a compressed summary of the possibililties for control and visualisation of the positio-

ning mode. Some of the parameters and functions are described in more detail in the corresponding chapters

Input functions (di.11...di.22)

No.

Name

Function

24

Activation positioning/ syn-

Activation of the positioning mode

chronous

29

Start positioning

Start of the positioning

Input "+" functions (di.24...di.35)

2

Store position (teach)

Positive edge stores an actual position as the target position in PS.24

Positive edge stores the actual position in parameter ru.71. Can be used

3

Scan position

for visualisation and generation of digital output signals.

4

Relative position F/R

Rotation setting for relative positioning (if selected in PS.27)

For connecting an adjustment sensor for flying referencing with adjust-

7

Reference point correction

ment.

Display parameters

Parameter

Function

Display of the actual position (calculated from the position informa-

ru.54

Actual position

tion of the encoder interface, selected in PS.01).

The position that the drive is supposed to have reached currently,

ru.56

Set position

according to the calculated profile (in contrast to ru.61 "target posi-

tion", to be reached at the end of the positioning).

7

ru.58

Angle difference

Difference between set and actual position.

ru.60

Act. position index

Number of the positioning block currently being processed.

The target which the drive should reach at the end of the positio-

ru.61

Target position

ning.

Maximum value of the speed profile the inverter calculates for opti-

ru.63

Profile speed

mal target approach.

The value by which the actual position is adjusted during the "flying

ru.69

Distance ref.-zeropoint

referencing with adjustment".

Position value scanned by a digital input (used for digital output and

ru.71

Teach / scan position

teaching).

If the drive rotates at the time of the "start positioning" command

(vector controlled operation or new pulse during a running positio-

ning), this parameter shows what distance to the actual position

ru.84

Accessible rel. position

the target must be to be reachable with the programmed ramp and

S-curve times. The ramp adjustment (PS.32) is not considered (see

chapter 7.12.4.13 "start positioning").

Page7.12 - 73

Positioning and Synchronous Control

Output switching conditions (do.00...do.07)

39

Angle difference > level

Angle difference ru.58 > comparison level (LE.00...LE.07)

The position profile is completed (ru.56 = ru.61) and the drive is in the

range of +/- PS.30 / 2 (target window) around the target position ru.61.

54

Target window reached

Is also set if the drive is stopped at an intermediate target during the se-

quential (index) positioning.

55

Current position > level

Actual position ru.54 > comparison level (LE.00...LE.07)

Positioning is active, but the set position ru.56 has not yet reached the

target position ru.61. The output is deactivated as soon as the calculated

56

positioning active

position profile reaches the target position, even if the drive has not stop-

ped in the target window yet. For the sequential positioning, the output is

deactivated if the drive has stopped at the target of a positioning block.

The position is inaccessible from the current speed in compliance with

the adjusted deceleration and S-curve times, or a new "start positioning"

57

position not reachable

command was given during the deceleration ramp (see chapter 7.12.4.14

"inaccessible positions"). PS.00 determines the behaviour of the drive.

This output switching condition is needed for the follow-up positioning.

The output is set with "start positioning". If the drive has reached the

target position of a positioning step, the output remains set (in contrast

58

Profile processing active

to Nr. 56). Only when the set position (ru.56) reaches the position of the

last block (PS.24), the output is deactivated again. In the last block, in

parameter PS.26 "next index", the value " -1: PS.28" must be entered.

path traversed since the last "start positioning" command is greater than

67

travelled path > level

the switching level.

Position to the target win-

path still to be travelled until reaching the target window is greater than

68

dow > level

the switching level.

Actual position index

=

For sequential positioning: the current position index is equal to the swit-

72

level

ching level (scaling factor: values of 0.51...1.5 count as index 1 etc.).

Amount act. position

-

Actual position (ru.54) - teach/scan position (ru.71) > comparison level

75

scan position > level

(LE.00...LE.07)

The output is set if the switching condition "target window reached" is

Actual Position = position

77

met (see Nr. 54) and the "act. position index" (ru.60) is equal to the "start

index PS.28

index new profile" (PS.28).

Only an initiator pulse within the position window of +/- PS.40 around the

reference point PS.17 may trigger an adjustment. If a pulse is received

Rotary table reference in-

78

outside of this window, it is interpreted as an interference pulse and is

valid

ignored. With this output switching condition, the user can recognize the

presence of invalid pulses.

The output is set if a "start positioning" command is ignored because the

Ignore position not reach-

new target position is "inaccessible" (see chapter 7.12.4.14 "inaccessible

79

able

positions"). The output is reset by a new "start positioning" command or

by deactivation of the positioning mode.

The switching level for the switching conditions are set in LE.00...LE.07. Since the switching level can be used

for very different quantities (current, voltage, speed, position, etc.), they have the following scaling factors for

comparisons with position values:

LE.00...LE.07 = 1,00 → comparison level is 100 increments

Page7.12 - 74

Positioning and Synchronous Control

Inverter state (ru.00)

No

Name

Function

Display of activation of the positioning mode (input "posi/sync activation" active

and positioning mode selected in PS.00). Whether the position controller is al-

Ready for posi-

121

ready active (i.e., whether the first "start positioning" command has been given),

tioning

or whether the drive is still in vector controlled operation, is not indicated by this

display. Missing limit switch signals also do not affect the status display.

Positioning

Positioning profile (position / speed profile) is being calculated. The set point posi-

122

active

tion ru.56 has not reached the target position ru.61 yet.

The position is inaccessible from the current speed under the restrictions of the

Position not

123

adjusted deceleration and S-curve times or a new "start positioning" command

reachable

was sent during the deceleration ramp.

7.12.5Contouring control mode

7.12.5.1

Contouring control mode / premises

For the contouring control mode, the bus-synchronous operation must be activated. Bus-synchronous operati-

on means that a control sends telegrams in a constant time pattern and that all connected inverters synchronise

to this pattern. This allows angular-synchronous and multi-axis operation, respectively.

To implement the bus-synchronous operation, one requires either a fast fieldbus system with the associated

KEB-operator or a fast control supporting the HSP5-protocol (e.g., a drive control COMBICONTROL C5).

The following bus systems are supported: CAN, SERCOS, EtherCAT, Powerlink, HSP5.

Fieldbus

KEB inver-

(e.g. CAN, SERCOS,

ter

EtherCat, Powerlink)

COMBICONTROL

7

F5A-S

KEB inverter

C5

or

optional

fieldbus

Drive

F5A-M

interface

interface

F5A-S

or

RS232

Parametrisation

F5A-M

digital

HSP5

I/O

Ethernet

Bus

Parametrisation

Visualisation

X3B

X3A

Encoder

Encoder

channel 2

channel 1

KEB

operator

X3B

X3A

Customer

Encoder

Encoder

control

channel 2

channel 1

type

How the bus-synchronous operation is realised and initialised depends on the fieldbus system used and must

be looked up in the instructions for the corresponding operator (CAN-operator, SERCOS operator, etc.). The

inverter enters the mode "bus-synchronous operation" if a value unequal to zero is set in parameter Sy.08 "bus

synchronisation time" .

Note: As soon as the control sends cyclic telegrams in the pattern set in Sy.08, the bit 9 "HSP5 bus synchro-

nous" is set in the status word (Sy.51). The synchronous communication can be monitored with this bit. The

control release may only be given if the assembly of the bus-synchronous operation is completed.

Page7.12 - 75

Positioning and Synchronous Control

7.12.5.2

Contouring control mode / settings

All parameters can be specified in bus-synchronous operation. Typically, however, this operating mode is used

for the contouring control mode. The activation of this mode is done in parameter PS.00 or via the control

word.

PS.00: Posi / synchronous mode

Bit

Meaning

Value

Explanation

0...5

Without function for contouring control

6: Contouring con-

Posi-/Synchro-

Selection of operating mode contouring control

0..2

trol

nous mode

The operating modes are selected via the control word (Sy.43

7: Via control word

or Sy.50).

Sy.50: Control word (low) /

Sy.43: control word (long)

Bit

Meaning

Value

Explanation

0: off

4096: Synchronous

Selection of operating mode synchronous running

Operating

running

12 / 13

mode

8192: positioning

Selection of operating mode positioning

12288: Contouring

Selection of operating mode contouring control

control

To activate the contouring control mode, the digital input occupied with the function "positioning / synchronous"

must be set.

In contouring control mode, the drive is positioned via the setting of a position setpoint value in the bus-syn-

chronous grid. The control, therefore, does not give the final target position but the set point position for each

individual cycle.

The inverter calculates the speed required to reach the position setpoint in one bus cycle. The setting of the

position setpoint can be done via PS.24 "index position" or via PS.34 "contouring mode position".

PS.33 "source contouring mode position" determines which parameter provides the setpoint position.

PS.33: Source contouring mode position

Value

Explanation

0:PS.34

The position is adopted as the setpoint position only if PS.34 is written to.

1:PS.24 or

The value is adopted as the setpoint position if PS.24 or PS.34 are written to. This setting is

PS.34

reasonable if a switch between positioning and countouring mode is desired.

Page7.12 - 76

Positioning and Synchronous Control

7.12.5.6

Contouring control mode / example

The drive shall meet the following requirements:

-

Position specification via PS.34

-

Speed specification via oP.03 if "0: off" is entered in "operating mode" (bit 12/ 13) of Sy.50 "control word

(low)"

-

Activation of the contouring mode via control word

-

bus synchronisation time 1000 µs

Parameter list:

Para.

Name

Value

Notice

General setting

Speed control

4: Speed con-

cs.00

Speed-controlled operation

configuration

trol

cs.01

Actual source

0: Channel 1

Speed feedback channel 1

2: digital abso-

oP.00

reference source

speed setpoint setting via oP.03

lute (op.3)

7: only setpoint

Direction of rotation from the setpoint sign, if the contouring

oP.01

Rotation source

sign

control mode is not activated

Settings for the position control in contouring control mode

Activation of the contouring mode via the control word (SY.50)

Attention: If the contouring mode is not activated in the control

Posi / synchro-

7: Via control

PS.00

word, the position value from encoder channel 1 is displayed

nous mode

word

in ru.54 "actual position". Thereby, the software limit switch

function, e.g., is not useable

Act. master

PS.01

1: Channel 2

Position feedback channel 2

source

Posi/synch input

If the contouring mode is selected in the control word, it is also

PS.02

1:ST

selection

immediately active

PS.06

KP pos/syn

100

Kp value for the position controller

Mode of position

The acquired position is valid (absolute encoder/ no approach

PS14

128

ref.

to reference point necessary)

Source con-

Position setpoint in the contouring control mode is set via

PS33

touring mode

0:PS.34

PS.34

position

Bus monitoring

HSP5 watchdog

Sy.09

0,01 (10ms)

smallest adjustable monitoring time

time

Pn.06

Watchdog time

0,01 (10ms)

smallest adjustable time for field bus monitoring

E.buS stopping

Pn.05

1

Quick stop/ modulation off/ no auto restart

mode

Page7.12 - 78

Positioning and Synchronous Control

Para.

Name

Value

Notice

Parametrisation of the bus-synchronous operation

Proc. read data 1

Sy.16

0236h

read ru.54 "Actual position"

definition

Proc. read data 1

Sy.17

1

Value immaterial since parameter is not set-programmable

set

Proc. read data 2

Sy.18

0033h

read SY.51 "status word (low)"

definition

Proc. read data 2

Sy.19

1

Value immaterial since parameter is not set-programmable

set

Proc. read data 3

Sy.20

-1: off

definition

Proc. read data 3

Sy.21

1

No third read parameter defined

set

Proc. write data 1

Sy.24

1322h

write PS.34 "Contouring mode position"

defin.

Proc. write data

Sy.25

255

Value immaterial since parameter is not set-programmable

1 set

Proc. write data 2

Sy.26

0303h

write oP.03 "reference setting"

defin.

Proc. write data

Sy.27

255

The value of oP.03 is adopted in all sets

2 set

Proc. write data 3

Sy.28

0032h

write SY.50 "control word (low)"

defin.

Proc. write data

Sy.29

255

Value immaterial since parameter is not set-programmable

3 set

7

Bus synchronisa-

Is written via the customer control or the COMBICONTROL

Sy.08

1000 us

tion time

C5

Page7.12 - 79

Positioning and Synchronous Control

7.12.6Position controller

The position controller is built as a P-controller. The increments per revolution of the encoder and the resolution

of the speed is considered in the controller. When swapping the encoder (e.g., from 1024 => 2500 increments)

or changing the speed range (e.g., from the 4000 to the 8000 speed mode by changing the parameter ud.02

"control type"), the speed controller setting can be applied.

The Kp of the position controller can be changed speed-dependently. Thereby, one can, e.g., choose a very

hard setting for the load transfer and the approach to the final position. For the remaining positioning,

the Kp is then lowered to achieve quiet operation of the drive and to dampen the effects of mechanical distur-

bances (like, e.g., seams in guide rails or similar).

The base value of the controller is set in PS.06 "KP positioning / synchronous". Parameter PS.08 "speed limit

for PS.07" determines up to which speed the lowering is to be implemented, and parameter PS.07 "KP speed

limit reduction" determines the percentage value the Kp shall still have in relation to its base value at the speed

PS.08.

The following figure illustrates this structure:

positioning module:

ru.63 Profile speed

Synchronous module:

ru.10 Encoder 2 speed

PS.06

oP.14 / oP.15

Kp position controller

absolute max.

Kp pos/syn

Setpoint value

ru.02

ramp output display

PS.07

+

PS.06

Kp speed limit reduction

(setpoint speed for

+

speed controller)

PS.07

PS.08

* PS.06

100 %

Speed limit

for PS.07

Speed

PS.08

KP

ru.56

Set position

+

ru.58

Angle difference

ru.54

-

Actual position

PS.09

Position limit

Posi/synchronous

Page7.12 - 80

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