Danfoss MCO 305 Design guide
MCO 305 Design Guide
Contents
How to Read this MCO 305 Design Guide..................................3
How to Read this Design Guide ......................................................................3
Symbols and Conventions .............................................................................5
Abbreviations ..............................................................................................5
Definitions ..................................................................................................6
Introduction to VLT Motion Control Option MCO 305..............11
What is VLT Motion Control Option MCO 305?................................................. 11
System Overview....................................................................................... 12
Configuration Examples ..............................................................................13
Interface between MCO 305, FC 300, and other Option Modules........................ 14
Control Loops ............................................................................................14
Encoder.................................................................................................... 15
Program Execution ..................................................................................... 15
Functions and Examples.........................................................17
Positioning ................................................................................................ 17
Synchronizing............................................................................................ 24
CAM Control .............................................................................................. 35
CAM Box................................................................................................... 46
Mechanical Brake Control ............................................................................47
Limited-Jerk.............................................................................................. 49
PC Software Interface ............................................................55
Specifics of the User Interface .....................................................................55
The APOSS Window.................................................................................... 56
The Edit Window........................................................................................ 58
File Menu..................................................................................................61
Edit Menu ................................................................................................. 62
Development Menu ....................................................................................64
Controller Menu .........................................................................................70
Tools Menu................................................................................................78
Settings Menu ........................................................................................... 79
Window Menu............................................................................................83
Help Menu ................................................................................................83
Download Menu .........................................................................................84
Debugging Programs ..................................................................................86
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APOSS Tools...........................................................................89
CAM-Editor ...............................................................................................89
Array Editor ............................................................................................ 105
APOSS Oscilloscope.................................................................................. 116
How to Program ...................................................................157
Programming the MCO with the APOSS Macro-language................................. 157
Basics .................................................................................................... 157
Preprocessor ........................................................................................... 172
APOSS Command Groups.......................................................................... 175
Get a General Idea of Program Samples ...................................................... 191
Parameter Reference............................................................195
FC 300, MCO 305, and Application Parameters ............................................. 195
FC 300 Parameters Overview ..................................................................... 197
Application Settings.................................................................................. 199
MCO Parameters ...................................................................................... 200
MCO Basics Settings................................................................................. 201
MCO Advanced Settings ............................................................................ 217
MCO Data Readouts.................................................................................. 238
Parameter Lists........................................................................................ 242
Troubleshooting ...................................................................251
Warnings and Error Messages .................................................................... 251
APOSS Software Messages ........................................................................ 259
Index....................................................................................261
Copyright © Danfoss A/S, 2010
Trademarks VLT is a registered Danfoss trademark.
Hiperface® is a registered trademark used for Rotational Position Sensors, Namely, Electronic Feedback Systems
For Motors and owned by Sick Stegmann GmbH, Max Stegmann GmbH Antriebstechnik-Elektronik.
Microsoft, Windows 2000, and Windows XP are either registered trademarks or trademarks of the Microsoft
Corporation in the USA and other countries.
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How to Read this MCO 305 Design Guide
How to Read this Design Guide
This Design Guide will introduce all aspects of your MCO 305. Please read also the Operating Instructions, in
order to be able to work with the system safely and professionally, particularly observe the hints and
cautionary remarks.
Chapter How to Read this Design Guide introduces the design guide and informs you about the
symbols, abbreviations, and definitions used in this
manual.
Page divider for ‘How to Read this Design Guide’.
Chapter Introduction to MCO 305 informs you
about the functionality and features of the
MCO 305, gives a system overview including
configuration examples, and informs you about
some basic topics like encoder and program
execution.
Page divider for ‘Int roduction’.
Chapter Functions and Examples guides you
through some applications examples from simple
positioning to different synchronizations as well as
CAM controls. Setting the parameters, programming of controls, and editing of curves can be
reconstructed in detail with these examples.
Page divider for ‘Fun ctions and Examples’.
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Chapter PC Software Interface informs you
about the APOSS specific menus and functions.
Click on → Help in the APOSS menu bar for more
details. Chapter APOSS Tools provides detailed
information about the CAM-Editor, Array-Editor as
well as the APOSS Oscilloscope.
Page divider for ‘PC Software Interface’.
Chapter How to Program shows you how to
program controls for the Frequency Converter
using MCO 305. This chapter provides a description
of all commands arranged in groups and all parameters in the Parameter Reference.
Page divider for ‘How to Program’.
Chapter Troubleshooting assists you in solving
problems that may occur when using the frequency
converter with MCO 305. The next section explains
the most important messages from the PC user
interface.
Page divider for ‘Trouble shooting’.
The manual ends with an index.
The Online Help provides in Chapter Program Samples almost 50 program samples which you can use to
familiarize yourself with the program or copy directly into your program.
Available Literature for FC 300, MCO 305, and MCT 10 Motion Control Tool
− The MCO 305 Operating Instructions provide the necessary information for built-in, set-up, and optimize
the controller.
− The MCO 305 Design Guide entails all technical information about the option board and customer design
and applications.
− This MCO 305 Command Reference completes the MCO 305 Design Guide with the detailed description of
all commands.
− The VLT® AutomationDrive FC 300 Operating Instructions provide the necessary information for getting
the drive up and running.
− The VLT® AutomationDrive FC 300 Design Guide entails all technical information about the drive and
customer design and applications.
− The VLT® AutomationDrive FC 300 MCT 10 Operating Instructions provide information for installation
and use of the software on a PC.
Danfoss Drives technical literature is also available online at www.danfoss.com/drives.
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Symbols and Conventions
Symbols used in this manual:
NB!:
Indicates something to be noted by the reader.
Indicates a general warning.
Indicates a high-voltage warning.
*
Indicates default setting.
Conventions
The information in this manual follows the system and uses the typographical features described below to
the greatest extent possible:
Menus and Functions
Menus and functions are printed italics, for example: Controller → Parameters.
Commands and Parameters
Commands and parameter names are written in capitals, for example: AXEND and KPROP; Parameters are
printed in italics, for example: Proportional factor.
Parameter Options
Values for use to select the parameter options are written in brackets, e.g. [3].
Keys
The names of keys and function keys are printed in brackets, for example the control key [Cntl] key, or just
[Cntl], the [Esc] key or the [F1] key.
Abbreviations
Automatic Motor Adaptation AMA
Control word CTW
Direct Current DC
Digital Signal Processor DSP
Frequency Converter FC
Local Control Panel LCP
Least significant bit LSB
Main actual value MAV
Motion Control Option MCO
Motion Control Tool MCT
Minute min
Most significant bit MSB
Main Reference MRV
Master Unit MU
Digital output switching to high side. NPN
Switch normally closed nc
Switch normally open no
Parameter par.
Position Control Loop PID
Digital output switching to low side. PNP
Pulses per Revolution PPR
Quad-counts qc
Reference REF
Revolutions per Minute RPM
Second, Millisecond s, ms
Sample time st
Status word STW
User Unit UU
Volts V
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Definitions
MLONG
An upper or lower limit for many parameters:
-MLONG = -1,073,741,824
MLONG = 1,073,741,823
Online / Offline Parameters
Changes to online parameters are activated immediately after the data value is changed. Changes to offline
parameters are not activated until you enter [OK] on the LCP.
Quad-counts
Incremental encoders: 4 quad-counts correspond
to one sensor unit.
Absolute encoders: 1:1 (1 qc correspond to one
sensor unit).
Through edge detection, a quadrupling of the increments is produced by both tracks (A/B) of the
incremental encoder. This improves the resolution.
Encoder Direction
The direction of encoder is determined by which
order the pulses are entering the drive.
Clockwise direction means channel A is 90 electrical degrees before channel B.
Counter Clockwise direction means channel B is
90 electrical degrees before A.
The direction determined by looking into the shaft
end.
Derivation of quad counts
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Virtual Master
Virtual master is an encoder simulation which
serves as a common master signal for
synchronization of up-to 32 axes.
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User Units
The units for the drive or the slave and the master, respectively, can be defined by the user in any way
desired so that the user can work with meaningful measurements.
Starting with MCO 5.00 the factors SYNCFACTM / SYNCFACTS, POSFACT_Z / POSFACT_N are no longer
limited to small values
Internally, it is act as follows: Whenever a value must be multiplied by the gear factor (i.e. master increments per ms), at first it is looked if a multiplication will result in an overflow. If so, a factor (64 bit) is used
which consists of
SYNCFACTS/SYNCFACTM to multiply the delta_master.
If no overflow occurs, first it is multiplied by SYNCFACTS and then divided by SYNCFACTM.
Concerning the error we are dealing with, this means:
Normal case
Multiplying by SYNCFACTS has no error, but dividing by SYNCFACTM means that the result may be wrong by
. That means that (worst case) such an error occurs every ms, i.e. that after 1193 hours (49,71 days)
1/2³²
we made an error of 1 qc (Slave).
Big factors
In that case, the used factor (SYNCFACTS/SYNCFACTM) itself could be wrong by 1/2³²
the worst case an error of delta_master * 1/2³²
occurs every ms. Assume that we have an encoder with
. This means that in
1000 counts (4000 qc) per revolution. Assume further, that we drive with 2000 rpm, i.e. we have a velocity
of 133 qc/ms. This means we make an error of 133 * 1/2³²
per ms. From this follows that in worst case
(maximum error every ms always in same direction) we could have an error of 1 qc after 9 hours.
This should not be relevant in most applications.
User Units [UU]
All path information in motion commands are made in user units and are converted to quad-counts
internally. These also have an effect on all commands for the positioning: e.g. APOS.
The user can also select meaningful units for the CAM control in order to describe the curve for the master
and the slave, for example 1/100 mm, or 1/10 degrees in applications where a revolution is being observed.
In the CAM control, the maximum run distance of the slave or the slave cycle length are indicated in User
Units UU (qc).
You can standardize the unit with a factor. This factor is a fraction which consists of a numerator and
denominator:
UU UnitUser 1 =
12-32 par.
11-32 par.
Numerator Unit User
Denomintor Unit User
par. 32-12 User Unit Numerator POSFACT_Z
par. 32-11 User Unit Denominator POSFACT_N
Scaling determines how many quad-counts make up a user unit. For example, if it is 50375/1000, then one
UU corresponds to exactly 50.375 qc.
NB!:
When user units are transferred into qc, then they get truncated. When qc are transferred into
user units, then they get rounded.
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Master Units [MU]
A factor (fraction) is used for the conversion into qc, as with the user unit:
1033 par.
par. 33-10 Synchronization Factor Master SYNCFACTM
par. 33-11 Synchronization Factor Slave SYNCFACTS
Open Loop vs. Closed Loop
Open loop is control without feedback. Closed loop control compares velocity or position feedback with the
commanded velocity or position and generates a modified command to make the error smaller. The error is
the difference between the required speed and the actual speed.
Open loop can be used on systems where motor velocity is not critical, and where accurate positioning is
not necessary. Applications such as fan and blower control, pump control, and some low-end home
appliances are examples.
MU UnitMaster 1
=
−
1133 par.
−
Master Factor ationSynchroniz
Slave Factor ationSynchroniz
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Introduction to VLT Motion Control Option MCO 305
What is VLT Motion Control Option MCO 305?
MCO 305 is an integrated programmable Motion Controller for VLT Automation Drive FC 312 and FC 312; it
adds functionality and flexibility to the already very comprehensive standard functionality of these drives.
FC 312 and FC 312 with MCO 305 is an intelligent drive offering highly accurate and dynamic motion control
featuring, Synchronization (electronic shaft), Positioning and electronic CAM control. In addition the programmability offers the possibility to implement a variety of application functions such as monitoring and
intelligent error handling.
Development of application programs for MCO 305 and configuration/commissioning is done via easy to use
PC software tools integrated in VLT Motion Control Tools MCT 10. The PC software tools includes programming editor with program examples, CAM profile editor as well as “test-run” and “scope” function for controller optimizing. MCO 305 is based on event controlled programming using a structured text programming
language developed and optimized for this application.
FC 312 can be delivered as an “all-in-one” drive with the MCO 305 module preinstalled or MCO 305 can be
delivered as option module for field installation.
Basic Features and specifications:
– Home function.
– Absolute and relative positioning.
– Software and Hardware end limits.
– Velocity, Position and Marker synchronizing.
– CAM control.
– Virtual master function for synchronizing of
multiple slaves.
– On-line adjustable gear-ratio.
– On-line adjustable offset.
– Definition of application parameters accessible
via FC 300 local control panel.
– Read/Write access to all FC 300 parameters.
– Sending and receiving data via Field-bus
interface (requires Field-bus option).
– Interrupts triggered by various events: Digital
input, position, Field-bus data, parameter
change, status change and time.
– Calculation, comparison, bit manipulation and
logical gating.
– Conditional and unconditional jumps.
– Graphical PID optimizing tool.
– Debugging tools.
– Supported encoder types: 5V Incremental
RS422 and SSI absolute single- and multi-turn,
Gray code, adjustable clock frequency and data
length.
– 3 supply voltages: 5V, 8V and 24V.
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System Overview
The MCO 305 system includes at least the following elements:
– FC 300.
– MCO 305 module.
– Motor/geared motor.
– Feedback encoder. Encoder must be mounted on motor shaft when operating FC 300 in Flux closed loop,
feedback encoder for positioning and synchronizing can be mounted anywhere in the application. See
“Encoders in applications” for more details.
– Master encoder (only for synchronizing).
– PC with MCT 10 for programming.
The following might also be required:
– Brake resistor for dynamic braking.
– Mechanical brake.
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Configuration Examples
One encoder used as motor feedback for closed
loop Flux control as well as position feedback.
One encoder used as motor feedback for closed
loop Flux control (connected via encoder option
MCB 102), linear encoder used as slave position
feedback and a third encoder as master.
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Interface between MCO 305, FC 300, and other Option Modules
The Interface between MCO 305 and the FC 300 control card provides read/write access to all parameters
as well as reading status of all inputs and the possibility to control all outputs. In addition various process
data such as status word and actual motor current can be read by the MCO 305 application program.
MCO 305 is controlling FC 300 via the speed/torque reference; see section “Control loops” for further
details.
Field-bus interface (e.g. PROFIBUS and
DeviceNet): MCO 305 has read/write access to
data received/send via the various Field-bus
interfaces (requires optional Field-bus option
module).
Relay option MCB 105: The relay outputs of MCB
105 can be controlled by the MCO 305 application
program.
General purpose I/O option MCB 103: Status of
inputs can be read and outputs can be controlled
via the MCO 305 application program.
Up-/download of MCO 305 application programs and configuration data is done via the FC 300 interfaces
(RS485 or USB) or via PROFIBUS DPV1 (requires optional PROFIBUS module). The same applies for the online PC software functions such as test-run and debugging.
Control Loops
MCO 305 has a PID (Proportional, Integral, Derivative) controller for position control based on actual
position (encoder feedback) and commanded position (calculated). The MCO 305 PID is controlling the
position in all modes of operation except velocity synchronizing where the velocity is controlled instead.
FC 300 is an “amplifier” in the MCO 305 control loop and it must therefore be optimized for the connected
motor and load before the MCO 305 PID can be set-up. FC 300 can be operated in open loop or closed loop
within the MCO 305 control loop, see example below:
Guideline for optimizing MCO 305 PID can be found in MCO 305 Operating Instructions.
Guideline for optimizing FC 300 can be found in FC 300 Operating Instructions.
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Encoder
MCO 305 supports various encoder types:
– Incremental encoder with RS422 signal type.
– Incremental encoder with sine–cosine signal type.
– Absolute encoder with SSI interface.
Master and feedback/slave encoder type can be selected independently; encoders can be rotary or linear.
Selection of encoder type depends on application requirements and general preferences. Attention must
however be paid to the resolution of the selected encoder. There are 3 important selection criteria:
– Maximum position accuracy is +/- 1 encoder increment.
– To ensure stable and dynamic control a minimum of 20 encoder increments per PID controller sample
period (default is 1 millisecond) is needed at the minimum application velocity.
– Maximum frequency of the MCO 305 encoder inputs must not be exceeded at maximum velocity.
The feedback encoder can be mounted directly on the motor shaft or behind gearboxes and/or other types
of transmissions. There are how ever some important issues to be aware of when mounting the encoder:
– There should be a firm connection between motor and encoder. Slip, backlash, and elasticity will reduce
control accuracy and stability.
– When the encoder is running at a low speed it must have a high resolution in order to meet the above
requirement (minimum 20 encoder increments per controller sample).
Program Execution
MCO 305 can store multiple programs, up-to 90. Only one of these programs can be executed at a time,
there are three ways to control which program to execute:
− Via parameter 33-80 Activated Program Number.
− Via digital inputs (parameters 33-50 through 33-59, 33-61 and 33-62).
− Via PC software.
One program must be defined as Autostart program, the Autostart program is automatically executed after
power up. Without Autostart program it is only possible to execute a program via PC software.
The Autostart program is always executed first, if the Autostart program is terminated (no loop or by EXIT
command) the following can happen:
1. When parameter 33-80 (Activated Program Number) = -1 and no input (parameters 33-50 through 33-
59, 33-61 and 33-62) is selected as Start program execution ([13] or [14]). The Autostart program will
restart.
2. When parameter 33-80 (Activated Program Number) ≠ -1 and no input (parameters 33-50 through 3359, 33-61 and 33-62) is selected as Start program execution ([13] or [14]). The selected program (par.
33-80) will be executed.
3. When an input (parameters 33-50 through 33-59, 33-61 and 33-62) is selected as Start program
execution ([13] or [14]) and one or more inputs are selected as Program select ([15]). The selected
program (Program select inputs) will be executed when the Start program execution input is activated.
The active program can be aborted via a digital input when defining an input as Break program execution
(Option [9] or [10] in 33-50 through 33-59, 33-61 and 33-62). The aborted program can be restarted via a
digital input when defining an input as Continue program execution (Option [11] or [12] in 33-50 through
33-59, 33-61 and 33-62).
Starting the Autostart program after power-up can be avoided by pressing the [Cancel] key of the FC 300
LCP during power-up. The key must be pressed until the message User abort (error 119) appears in the
display.
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A temporary program can be executed from the program editor (MCT10/APOSS), temporary programs are
only stored in RAM and are thus lost at power-down. The temporary program can also be executed in a
special Debug mode where it is possible to influence the program execution as well as reading out data and
variables, see on-line help of APOSS for further details.
When connecting a PC with MCT 10 to the drive, the active program might be aborted e.g. when
downloading a new program or when working with the program editor ([Esc] will abort program
execution).
NB!:
In case of an error the active program will be terminated if no error handler (ON ERROR GOSUB
xxxx) is defined and the program will not be restarted.
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Functions and Examples
Positioning
Basically the term positioning in connection with drives means moving the shaft to a specific position. In
order to obtain accurate positioning it is necessary to use a closed loop system to control the actual
position, based on position feedback from an encoder.
A positioning procedure with a closed loop positioning controller requires the following: Set velocity,
acceleration, deceleration and a target position; a velocity profile is calculated based on the actual position
of the shaft as well as the before mentioned parameters; the shaft is moved according to the velocity profile
until the target position is reached.
Typical applications where accurate positioning is required:
− Palletizers, for example stacking boxes on a pallet.
− Index tables, for example filling material into trays on a rotating table.
− Conveyors, for example when cutting material to length.
− Hoists, for example a lift stopping at different levels.
MCO 305 offers three main positioning types
− Absolute
− Relative
− Touch Probe
Absolute Positioning
Absolute positioning always relates to the absolute zero point of the system, this also means that the absolute zero point must be defined before an absolute positioning procedure can be conducted. When using
incremental encoders the zero point is defined by means of a Home function, where the drive approaches a
reference switch, stops and defines the actual position as zero. When using absolute encoders the zero
point is given by the encoder.
If the starting position is 0 and with an absolute positioning to 150.000 the target position is 150.000, the
drive will thus move a distance of 150.000. If on the other hand the starting position is 100.000 and with an
absolute positioning to 150.000 the target position is still 150.000 but the drive will only move a distance of
50.000 because it moves to position 150.000 related to the zero point.
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__ Functions and Examples __
Relative Positioning
Relative positioning is always relating to the actual position, it is therefore possible to execute a positioning
procedure without defining the absolute zero point.
If the starting position is 100.000, with a relative positioning to 150.000 the target position is 250.000
(100.000 + 150.000), the moving distance is thus 150.000.
Touch Probe Positioning
With touch probe positioning, the positioning is related to the actual position when the touch probe input is
activated, that means the target position is the position of the touch probe + the positioning distance. Touch
probe positioning is thus relative positioning relating to a touch probe instead of the actual starting position.
The touch probe is a sensing device; it can be a mechanical switch, a proximity sensor, an optical sensor or
the like. Once the touch probe is activated, for example by a box moved on a conveyor belt, the reference
for the positioning is set.
With touch probe positioning to position 50.000 the drive is running until the touch probe is activated for
example at position 200.000 and it continues to a target position of 250.000 (200.000 + 50.000). Touch
probe positioning is also called “marker related positioning”.
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Application Example: A Bottle Box Palletizer
The following samples show a palletizer stacking
boxes with bottles. The boxes are unloaded using a
pack gripper. The three positioning modes are used
in this sample and explained in three steps.
NOTE: The following are just examples and the
presented settings and programs might not cover
the complete functionality required by a real
application.
It is assumed that the motor and encoder connections are checked and that all basic parameter
settings such as motor data, encoder data and PID
controller are done. Instructions for setting up parameters can be found in FC 300 Operating
Instructions and MCO 305 Operating Instructions.
Absolute Positioning
Absolute Positioning is explained with following function of the palletizer: The horizontal axis has two fixed
target positions; one is above the pick-up and the other one is above the pallet. The horizontal axis is controlled with absolute positioning between the pick-up position and the deliver position.
Parameter Settings and Commands for Palletizer Application
The following MCO 305 parameters are relevant for
absolute positioning:
32-0* Encoder 2 – Slave page
32-6* PID-Controller page
32-8* Velocity & Acceleration page 213
33-0* Home Motion page 217
33-4* Limit Handling page
Command Description Syntax Parameter
Absolute Positioning (ABS)
ACC Sets acceleration ACC a a = acceleration
DEC Sets deceleration DEC a a = deceleration
HOME Move to device zero point (reference switch) and set
as the real zero point.
POSA Positions axis absolutely POSA p p = position in UU
VEL Sets velocity for relative and absolute motions and
set maximum allowed velocity for synchronizing
HOME –
VEL v v = scaled velocity value
201
210
229
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__ Functions and Examples __
Program Example: Absolute Positioning for Palletizer Application
/********************** Absolute Positioning program sample **************************/
// Inputs: 1 Go to pick up position
// 2 Goto deliver position
// 3 Home switch
// 8 Clear Error
// Outputs: 1 In pick up position
// 2 In deliver position
// 8 Error
/****************************** Interrupts **************************************/
ON ERROR GOSUB errhandle
// In case of error go to error handler routine, this must always be included
/**************************** Basic settings ***********************************/
VEL 80 // Sets positioning velocity related to par. 32-80 Maximum velocity
ACC 100 // Sets positioning acceleration related to par. 32-81 Shortest ramp
DEC 100 // Sets positioning deceleration related to par. 32-81 Shortest ramp
/*********************** Define application parameters *****************************/
LINKGPAR 1900 "Pick up Position" 0 1073741823 0
LINKGPAR 1901 "Deliver Position" 0 1073741823 0
/****************** Define Home(0) position after power up *************************/
SET I_FUNCTION_3 1 // Define input 3 as Home switch input
HOME // Go to Home and set position to 0
/****************************** main loop **************************************/
MAIN:
IF (IN 1 == 1) AND (IN 2 == 0) THEN // Go to pick up position when only input 1 is high
OUT 2 0 // Reset "In deliver position" output
POSA (GET 1900) // Go to position
OUT 1 1 // Set "In pick up position" output
ELSEIF (IN 1 == 0) AND (IN 2 == 1) THEN // Go to deliver position when only input 2 is high
OUT 1 0 // Reset "In pick up position" output
POSA (GET 1901) // Go to position
OUT 2 1 // Set "In deliver position" output
ELSE
MOTOR STOP // Stop if both inputs are low or high.
ENDIF
GOTO MAIN
/*********************** Sub programs start *************************************/
SUBMAINPROG
/************************* Error handler ****************************************/
SUBPROG errhandle
err = 1 // Set error flag to remain in error handler until error is reset.
OUT 8 1 // Set error output
WHILE err DO // Remain in error handler until the reset is received
IF IN 8 THEN // Reset error when Input 8 is high.
ERRCLR // Clear error
err=0 // Reset error flag
ENDIF
ENDWHILE
OUT 8 0 // Reset error output
RETURN
/*****************************************************************************/
ENDPROG
/*************************** End of program ************************************/
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__ Functions and Examples __
Relative Positioning
Relative Positioning is explained with following function of the palletizer: When leaving the deliver position
the vertical axis just needs to move up one box height so that it is clear of the stack before the horizontal
axis can move back to the pick-up position. This is done by relative positioning to “box height” in the “updirection”.
Parameter Settings and Commands for Palletizer Application (Relative Positioning)
The following MCO 305 parameters are relevant for
relative positioning:
Command Description Syntax Parameter
Relative Positioning (REL)
ACC Sets acceleration ACC a a = acceleration
DEC Sets deceleration DEC a a = deceleration
POSR Positioning relative to the actual position POSR d d = distance to actual position in UU
VEL Sets velocity VEL v v = scaled velocity value
32-0* Encoder 2 – Slave page
32-6* PID-Controller page 210
32-8* Velocity & Acceleration page
201
213
Program Example: Relative Positioning for Palletizer Application
/********** Relative positioning sample program for palletizer application example **********/
// Inputs: 1 Go to position
// 8 Clear Error
// Outputs: 1 In position
// 8 Error
/*************************** Interrupts *****************************************/
ON ERROR GOSUB errhandle
// In case of error go to error handler routine, this must always be included
/************************ Define flags *****************************************/
flag = 0
/********************* Basic settings ****************************************/
VEL 80 // Sets positioning velocity related to par. 32-80 Maximum velocity.
ACC 100 // Sets positioning acceleration related to par. 32-81 Shortest ramp.
DEC 100 // Sets positioning deceleration related to par. 32-81 Shortest ramp.
/******************* Define application parameters *********************************/
LINKGPAR 1900 "Box high" 0 1073741823 0
/************************** main loop *****************************************/
MAIN:
IF (IN 1 == 1) AND (flag == 0) THEN // Go to position once (ensured by flag) when input 1 is high.
OUT 1 0 // Reset "In position" output.
POSR (GET 1900) // Go to position.
OUT 1 1 // Set "In position" output.
flag = 1 // Set "flag" to ensure that distance is only traveled once.
ELSE
MOTOR STOP // Stop if input is low.
flag = 0 // Reset "flag" to enable new positioning.
ENDIF
GOTO MAIN
/********************** Sub programs start **************************************/
SUBMAINPROG
/************************ Error handler *****************************************/
SUBPROG errhandle
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MCO 305 Design Guide
__ Functions and Examples __
err = 1 // Set error flag to remain in error handler until error is reset.
OUT 8 1 // Set error output.
WHILE err DO // Remain in error handler until the reset is received.
IF IN 8 THEN // Reset error when Input 8 is high.
ERRCLR // Clear error.
err=0 // Reset error flag.
ENDIF
ENDWHILE
OUT 8 0 // Reset error output.
flag = 0 // Reset "flag" to enable new positioning.
RETURN
/*****************************************************************************/
ENDPROG
/********************* End of program *****************************************/
Touch Probe Positioning
Touch Probe is explained with following function of the palletizer:
When the horizontal axis is in the deliver position the vertical axis has numerous target positions depending
on the height of the already stacked boxes, which again depends on the box height and the number of
layers of boxes. This is controlled with Touch probe positioning where the touch probe detects the top of the
stack in order to calculate the deliver position on top of the stack.
Parameter Settings and Commands for Touch Probe Application
The following MCO 305 parameters are relevant for
touch probe positioning:
32-0* Encoder 2 – Slave page
32-6* PID-Controller page 210
32-8* Velocity & Acceleration page 213
33-4* Limit Handling page
201
229
Command Description Syntax Parameter
Touch Probe
ON INT Defining an interrupt input. ON INT n
GOSUB name
ACC Sets acceleration. ACC a a = acceleration
DEC Sets deceleration. DEC a a = deceleration
POSR Positioning relative to the actual
position.
CVEL Sets velocity for speed controlled
motor movements.
CSTART Starts the speed mode. – –
POSR d d = distance to actual position in UU
CVEL v v = velocity value (negative value for
n = number of the input to be monitored
1 - 8 = reaction to the rising edge
–1 - 8 = reaction to the falling edge
name = subroutine name
reversing)
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__ Functions and Examples __
Program Example: Touch Probe Positioning for Palletizer Application
/******** Touch probe positioning sample program for palletizer application example *********/
// Inputs: 1 Go to position
// 2 Touch probe
// 8 Clear Error
// Outputs: 1 In position
// 8 Error
/********************************* Interrupts ************************************/
ON ERROR GOSUB errhandle // In case of error go to error handler routine, this must always be included
ON INT 2 GOSUB tp_handler // Call touch probe handler on positive edge of input 2.
/******************************* Define flags ***********************************/
flag = 0
tp_active = 0
/***************************** Basic settings **********************************/
VEL 80 // Sets positioning velocity related to parameter 32-80 Maximum velocity.
ACC 100 // Sets positioning acceleration related to parameter 32-81 Shortest ramp.
DEC 100 // Sets positioning deceleration related to parameter 32-81 Shortest ramp.
/************************** Define application parameters ***************************/
LINKGPAR 1900 "Touch probe distance" 0 1073741823 0
/******************************* main loop **************************************/
MAIN:
IF (IN 1 == 1) AND (flag == 0) THEN // Start movement once (ensured by flag) when input 1 is high.
OUT 1 0 // Reset "In position" output.
CVEL 80 // Set constant velocity.
CSTART // Start with constant velocity.
tp_active = 0 // Reset "tp_active" to enable new touch probe positioning.
flag = 1 // Set "flag" to ensure that distance is only traveled once.
ELSE
MOTOR STOP // Stop if input is low.
flag = 0 // Reset "flag" to enable new start.
ENDIF
GOTO MAIN
/****************************** Sub programs start *******************************/
SUBMAINPROG
/****************************** Touch probe handler ******************************/
SUBPROG tp_handler
IF (tp_active == 0) THEN
POSR (GET 1900) // Go to touch probe target position
WAITAX // Halt program execution until position is reached (This is necessary as
// NOWAIT ON is automatically set in a subroutine called by interrupt).
OUT 1 1 // Set "In position" output.
tp_active = 1 // Set "tp_active" to ensure that touch probe positioning is done only once
ENDIF
RETURN
/******************************** Error handler *********************************/
SUBPROG errhandle
err = 1 // Set error flag to remain in error handler until error is reset.
OUT 8 1 // Set error output.
WHILE err DO // Remain in error handler until the reset is received.
IF IN 8 THEN // Reset error when Input 8 is high.
ERRCLR // Clear error.
err=0 // Reset error flag.
ENDIF
ENDWHILE
OUT 8 0 // Reset error output.
flag = 0 // Reset "flag" to enable new positioning.
RETURN
/*****************************************************************************/
ENDPROG
/******************************** End of program ********************************/
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__ Functions and Examples __
Synchronizing
Synchronizing is used in applications where 2 or more shafts need to follow each other in velocity or position. It can be a simple master-slave system where a slave is following the velocity or position of a master
or it can be a multi-axis system where multiple slaves are following the velocity or position of a common
master signal. Electronic synchronization is very flexible compared to a mechanical shaft, belt or chain as
the gear-ratio and position offset can be adjusted during operation. Velocity and position of the slave drive
is controlled based on a master encoder signal, a feedback encoder signal as well as the set gear-ratio.
During synchronization the slave is always restricted by maximum velocity and acceleration/ deceleration
(parameter group 33-8*). In addition the allowed deviation between master and slave velocity can be
restricted by parameter 33-14, e.g. 33-14 = 5% means that the slave can only be 5% faster or slower than
actual master velocity when doing position corrections.
MCO 305 offers 3 basic types of synchronization:
For synchronous operation of two or more drives you can use
− Velocity synchronization
− Position synchronization
− Marker synchronization
Velocity Synchronization (SYNCV)
Velocity synchronization (SYNCV) is closed loop velocity control where the set-point is the master velocity
multiplied by the gear-ratio and the actual velocity is measured by the slave encoder; position deviations
will not be corrected. Note however that using the Integral part of the PID controller will lead to some level
of position correction as the integral sum of velocity is equal to position.
The slave must be at least as fast and dynamic as
the master in order to maintain accurate synchronization, i.e. the slave must be able to match the
maximum velocity, acceleration and deceleration of
the master. Already during the design phase it is
thus important to consider making the least dynamic shaft the master as this shaft will anyway be
the limiting factor for the system performance.
Typical applications are:
− Synchronizing of two or more conveyors
− Material stretching
− Mixing
Application Example: Suit Case Conveyor Belt
Control behavior with velocity synchronization.
Two or more conveyor belts must run at the same
speed in order to get a smooth transfer of the suit
case from one conveyor belt to the next.
In addition to start and stop of velocity synchronizing the sample program has a manual mode with
the possibility to increase and decrease the velocity
via digital inputs.
NOTE: The following is just an example and the presented settings and programs might not cover the
complete functionality required by a real application.
It is assumed that the motor and encoder connections are checked and that all basic parameter settings
such as motor data, encoder data and PID controller are done. Instructions for setting up parameters can
be found in FC 300 Operating Instructions and MCO 305 Operating Instructions.
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__ Functions and Examples __
Parameter Settings and Commands for Conveyor Belt Application
The following MCO 305 parameters are relevant for
velocity synchronization:
Command Description Syntax Parameter
SYNCV Synchronization of velocity SYNCV –
ON ERROR GOSUB Definition of an error subroutine
Program Example: Velocity Synchronizing
/************************ Velocity synchronizing sample program ***********************/
// Inputs: 1 Start/stop synchronization
// 2 Start manual mode
// 3 Increase manual velocity
// 4 Decrease manual velocity
// 8 Clear Error
// Outputs: 1 In synchronizing mode
// 2 In manual mode
// 8 Error
/********************************* Interrupts **************************************/
ON ERROR GOSUB errhandle // In case of error go to error handler routine, this must always be included
/***************************** Basic settings *************************************/
VEL 100 // Sets maximum slave velocity related to parameter 32-80 Maximum velocity
ACC 100 // Sets slave acceleration related to parameter 32-81 Shortest ramp
DEC 100 // Sets slave deceleration related to parameter 32-81 Shortest ramp
/************************** Define application parameters *****************************/
LINKGPAR 1900 "Manual velocity" 0 100 0
LINKGPAR 1901 "Velocity step" 0 10 0
/*************************** Define flags and variables *******************************/
sync_flag = 0
done = 0
err = 0
man_vel = 0
/********************************** main loop *************************************/
MAIN:
IF (IN 1 == 1) AND (sync_flag == 0) THEN // Start synchronizing once when input 1 is high
SYNCV // Start velocity synchronizing mode
sync_flag = 1 // Set sync_flag to ensure synchronizing is only started once.
OUT 1 1 // Set "In synchronizing mode" output
ELSE
MOTOR STOP // Stop if input 1 is low.
sync_flag = 0 // Reset sync_flag after stop
OUT 1 0 // Reset "In synchronizing mode" output
ENDIF
IF (IN 2 == 1) AND (sync_flag == 0) THEN // Start manual mode if input 2 high and not synchronizing
OUT 2 1 // Set "In manual mode" output
man_vel = GET 1900 // Set manual velocity to parameter 1900
CVEL man_vel
CSTART // Start constant velocity mode
WHILE (IN 2 == 1) DO // Stay in manual mode while input 2 is high
CVEL man_vel // Update manual velocity
IF (IN 3 == 1) AND (done == 0) THEN // Increase manual velocity by one step when input 3 is set
32-0* Encoder 2 – Slave page
32-3* Encoder 1 – Master page 205
32-6* PID-Controller page
32-8* Velocity & Acceleration page 213
33-1* Synchronization page 218
ON ERROR GOSUB
name
name = name of the subroutine
201
210
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__ Functions and Examples __
man_vel = man_vel + GET 1901
done = 1
ELSEIF (IN 4 == 1) AND (done == 0) THEN // Decrease manual velocity by 1 step when input 3 is set
man_vel = man_vel - GET 1901
done = 1
ELSE
done = 0
ENDIF
ENDWHILE
CSTOP // Stop when leaving manual mode
OUT 2 0 // Reset "In manual mode" output when leaving manual mode
ENDIF
GOTO MAIN
/****************************** Sub programs start ********************************/
SUBMAINPROG
/******************************** Error handler ***********************************/
SUBPROG errhandle
err = 1 // Set error flag to remain in error handler until error is reset.
OUT 8 1 // Set error output
OUT 1 0 // Reset "In synchronizing mode" output in case of error
OUT 2 0 // Reset "In manual mode" output in case of error
WHILE err DO // Remain in error handler until the reset is received
IF (IN 8) AND NOT (IN 1) AND NOT (IN 2) THEN
// Reset error when Input 8 is high and input 1+2 is low.
ERRCLR // Clear error
err=0 // Reset error flag
ENDIF
ENDWHILE
OUT 8 0 // Reset error output
sync_flag = 0 // Reset sync_flag after an error
done = 0 // Reset done flag after an error
RETURN
/*******************************************************************************/
ENDPROG
/******************************* End of program **********************************/
Position/Angle Synchronization (SYNCP)
Position synchronization (SYNCP) is closed loop position control with a moving target where the set-point
(commanded position) is the master position multiplied by the gear-ratio also considering any position offset. The slave position is controlled based on this set-point and the actual position feedback from the slave
encoder. Any position deviation will continuously be corrected considering maximum velocity, acceleration
and deceleration of the slave. The gear-ratio is set as a fraction (numerator and denominator) to avoid
rounding errors e.g. when using prime numbers. The gear-ratio must be 100% correct, even the smallest
rounding error will lead to position drifting over time.
When starting position synchronizing the actual slave position will be locked to the actual master position, it
is thus necessary to bring the slave into the right physical position with respect to the physical position of
the master. This can be done manually or be means of an automatic homing procedure (requires external
reference switches or absolute encoders).
The slave must be faster and more dynamic than the master in order to maintain accurate synchronization
both at maximum master velocity and during acceleration/deceleration. I.e. the slave must be able to
exceed the maximum velocity, acceleration and deceleration of the master to allow it to catch up if getting
behind the master. Already during the design phase it is thus important to consider making the least dynamic shaft the master as this shaft will anyway be the limiting factor for the system performance.
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__ Functions and Examples __
Typical applications are:
− Bottle washing machines.
− Foil wrapping.
− Packaging machines.
− Conveyors.
− Multi axis hoists.
− Filling.
− Printing.
− Cut on the fly.
Control behavior with position synchronization
Application Example: Packaging with Fixed Product Distances
This application consists of two conveyors, 1 carrying empty boxes another one carrying teddy bears;
the purpose of the machine is to put teddies into the
boxes. Both boxes and teddies come with a fixed
distance and it is ensured that there is no slip
between the encoders and the boxes and teddies. It
is thus sufficient to position synchronize based on
the encoders. At start it is ensured that the master
(box conveyor) it always in the same position, the
teddy conveyor needs to be homed prior to starting
synchronization. There are 3 ways to ensure that
the teddies are aligned with the boxes when
starting:
− Adjust the physical position of the home/reference switch.
− Adjust home offset in parameter 33-01.
− Adjust position offset for synchronization in parameter 33-12.
NOTE: The following is just an example and the presented settings and programs might not cover the
complete functionality required by a real application.
It is assumed that the motor and encoder connections are checked and that all basic parameter settings
such as motor data, encoder data and PID controller are done. Instructions for setting up parameters can
be found in FC 300 Operating Instructions and MCO 305 Operating Instructions.
Parameter Settings and Commands for Packaging Application
The following MCO 305 parameters are relevant for
position synchronization:
MG.33.L5.02 – VLT® is a registered Danfoss trademark 27
32-0* Encoder 2 – Slave page
201
32-3* Encoder 1 – Master page 205
32-6* PID-Controller page
210
32-8* Velocity & Acceleration page 213
33-1* Synchronization page 218
MCO 305 Design Guide
__ Functions and Examples __
Command Description Syntax Parameter
DEFSYNCORIGIN Defines master-slave relation for the
next SYNCP or SYNCM command
MOVESYNCORIGIN Relative shifting of the origin of
synchronization
PULSACC Sets acceleration for master
simulation
PULSVEL Sets velocity for master simulation PULSVEL v v = velocity in pulses per second
SYNCP Synchronization of angle/position SYNCP –
SYNCSTAT Queries flag for synchronization
status
SYNCERR Queries actual synchronization error
of the slave
DEFSYNCORIGIN
master slave
MOVESYNCORIGIN
mvalue
PULSACC a a = acceleration in Hz/s
res = SYNCSTAT –
res = SYNCERR –
master = reference position in qc
slave = reference position
mvalue = Relative offset
(Hz)
Position Synchronizing Sample Program
/************************* Position Synchronizing Sample Program ***********************/
// Inputs: 1 Start/stop synchronization
// 2 Start homing
// 3 Home switch
// 4 Increase offset
// 5 Decrease offset
// 8 Clear Error
// Outputs: 1 Within synchronizing accuracy, set accuracy window in par. 33-13
// 2 Homing done
// 8 Error
/****************************** Interrupts **************************************/
ON ERROR GOSUB errhandle
// In case of error go to error handler routine, this must always be included
/************************** Basic settings ************************************/
VEL 100 // Sets maximum slave velocity related to par. 32-80 Maximum velocity
ACC 100 // Sets slave acceleration related to par. 32-81 Shortest ramp
DEC 100 // Sets slave deceleration related to par. 32-81 Shortest ramp
/*********************** Define application parameters *****************************/
LINKGPAR 1900 "Offset step" 0 10000 0
LINKGPAR 1901 "Offset type" 0 1 0
/********************** Set parameters and flags ********************************/
SET I_FUNCTION_3 1 // Define input 3 as Home switch input
next_step = 0
home_done = 0
new_offset = 0
/************************************* main loop ******************************/
MAIN:
IF (IN 2 == 1) THEN // Start homing if input 2 high
HOME // Go to Home and set position to 0
home_done = 1 // Set home_done flag
OUT 2 1 // Set home done output
ENDIF
IF (IN 1 == 1) AND (home_done == 1) THEN // Start synchronizing when input 1 = 1 and homing done.
SYNCP // Start position synchronizing mode
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__ Functions and Examples __
old_offset = GET SYNCPOSOFFS
WHILE (IN 1 == 1) DO // Stay in synchronizing mode while input 1 = 1
IF (IN 4 == 1) THEN
GOSUB increase_offset
ELSEIF (IN 5 == 1) THEN
GOSUB decrease_offset
ENDIF
IF (SYNCSTAT & 4) THEN
OUT 1 1
ELSE
OUT 1 0
ENDIF
ENDWHILE
MOTOR STOP // Stop if input 1 is low.
home_done = 0 // Reset home_done flag after stop
OUT 1 0
OUT 2 0 // Reset home done output after stop
IF (new_offset != old_offset) AND (GET 132 == 0) THEN // Save absolute offset if changed
SAVE AXPARS // NOTE: Saving more that 10000 times can damage flash PROM
ENDIF
ENDIF
GOTO MAIN
/*************************** Sub programs start *********************************/
SUBMAINPROG
/***************************** Increase offset **********************************/
SUBPROG increase_offset
IF (Next_step) THEN // Check if next offset step is enabled
IF (GET 1901 == 0) THEN // Absolute offset
new_offset = old_offset + GET 1900 // Read existing offset and add step value
SET SYNCPOSOFFS new_offset // Set new position offset
ELSE // Relative offset
MOVESYNCORIGIN GET 1900 // Execute relative offset with offset step
ENDIF
ENDIF
Next_step=0 // Disable next offset step
ON TIME 500 GOSUB Enb_Step // Enable next offset step after 500 ms
RETURN
/*************************** Decrease offset ***********************************/
SUBPROG decrease_offset
IF (Next_step) THEN // Check if next offset step is enabled
IF (GET 1901 == 0) THEN // Absolute offset
new_offset = GET SYNCPOSOFFS - GET 1900
// Read existing offset and subtract step value
SET SYNCPOSOFFS new_offset // Set new position offset
ELSE // Relative offset
MOVESYNCORIGIN (- GET 1900) // Execute relative offset with - offset step
ENDIF
ENDIF
Next_step=0 // Disable next offset step
ON TIME 500 GOSUB Enb_Step // Enable next offset step after 500 ms
RETURN
/************************* Enable new offset step *******************************/
SUBPROG Enb_step
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__ Functions and Examples __
Next_step = 1 // Enable next offset step
RETURN
/***************************** Error handler ***********************************/
SUBPROG errhandle
err = 1 // Set error flag to remain in error handler until error is reset.
OUT 8 1 // Set error output
OUT 2 0 // Reset home done output in case of error
WHILE err DO // Remain in error handler until the reset is received
IF (IN 8) AND NOT (IN 1) THEN // Reset error when Input 8 is high and input 1 low.
ERRCLR // Clear error
err=0 // Reset error flag
ENDIF
ENDWHILE
OUT 8 0 // Reset error output
home_done = 0 // Reset home_done flag after an error
RETURN
/****************************************************************************/
ENDPROG
/***************************** End of program *********************************/
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