Emerson PCM-22 User manual

PCM-22
Rotary Knife Controller
Information furnished by EMERSON Motion Control is believed to be accurate and reliable. However,
no responsibility is assumed by EMERSON Motion Control for its use. EMERSON Motion Control
reserves the right to change the design or operation of the equipment described herein and any
associated motion products without notice. EMERSON Motion Control also assumes no responsibility
for any errors that may appear in this document. Information in this document is the property of
EMERSON Motion Control and is subject to change without notice.
P/N 400274-01
Rev.: A2
Date: December 7, 1998
© 1998 EMERSON Motion Control. All Rights Reserved.

PCM-22 Rotary Knife Controller
ii © EMERSON Motion Control
© 1998 EMERSON Motion Control. All Rights Reserved.
Document Number: 400274-01
No part of this manual may be reproduced by any means without the written permission of EMERSON Motion
Control.
EMERSON Motion Control is a registered trademark of EMERSON ELECTRIC.
Printed in U.S.A.
December, 1998 Revision A2
This document has been prepared to conform to the current release version of the PCM-22 Rotary Knife
Controller. Because of our extensive developments and our desire to further improve and enhance the product,
inconsistencies may exist between the product and documentation in some instances. Call your customer
support representative if you encounter an inconsistency.

P/N 400274-01 Revision A7 iii
Customer Services
EMERSON Motion Control offers a wide range of services to support our
customers’ needs. Listed below are some of these services.
Application Engineering [phone]
E-Mail: [email protected]
An experienced staff of factory application engineers provide complete
customer support for tough or complex applications. Our engineers offer
you a broad base of experience and knowledge of electronic motion
control applications.
EMERSON BBS [phone]
EMERSON Motion Control maintains a electronic Bulletin Board
System which provides you access to software updates, technical
information and services.
Communications protocol: 300 - 28,800 Baud, N, 8, 1.
FAX [phone]
Internet Access www.emersonemc.com
Order / Repair Status [phone]
Sales (800) FX-SERVO
E-Mail: [e-mail]
Service Support [phone]
E-Mail: [email protected]
EMERSON Motion Control’s products are backed by a team of
professionals who will service your installation wherever it may be. Our
customer service center in Minneapolis Minnesota is ready to help you
solve those occasional problems over the telephone. Our customer service
center is available 24 hours a day for emergency service to help speed
any problem solving. Also, hardware replacement parts, should they ever
be needed, are available through our customer service organization.
Need on-site help? EMERSON Motion Control provides on-site service,
in most cases, the next day. Just call EMERSON’s customer service
center when on-site service or maintenance is required.
See Service Support Check List on the following page.
Training Services [phone]
EMERSON Motion Control maintains a highly trained staff of
instructors to familiarize customers with EMERSON Motion Control
products and their applications. A number of courses are offered, many
of which can be taught in your plant upon request.

PCM-22 Rotary Knife Controller
iv © EMERSON Motion Control
Service Support Check List
To ensure the most timely and efficient support possible, please have the
following items ready before calling for Service Support.
1. The model and serial number(s) of your FX Amplifier(s) and
manual(s).
2. The model and serial number(s) of your PCM(s).
3. The result (using Terminal Mode) of ID?; 0ID? (zero ID?) if axis ID’s
are used.
4. The result (using Terminal Mode) of ID1?; 0ID1? (zero ID1?) if axis
ID’s are used.
5. A description of the symptom(s) or issue(s) observed including any
fault status codes displayed on the LED Diagnostic Display.
6. Copies of the current uploaded program(s) that are in each of your
PCM(s).
7. The gear ratio, model number and type of reducer(s) used.
8. This manual.

P/N 400274-01 Revision A7 v
Table Of Contents
Introduction 1
Description ................................................................................................................... 1
Features ........................................................................................................................ 3
Terminology ................................................................................................................. 4
Master Cycle Length .............................................................................................. 4
Follower Cycle Length ........................................................................................... 4
Working Segment .................................................................................................. 5
Cycle Point............................................................................................................. 5
Working Offset....................................................................................................... 5
Variable Segment................................................................................................... 6
Cycle Drop Out Position......................................................................................... 7
Working Ratio........................................................................................................ 7
Phase...................................................................................................................... 8
Average Length...................................................................................................... 8
Theory of Operation 11
General Running......................................................................................................... 11
Master Cycle Defined By Sensor Mode................................................................. 12
Master Cycle Not Defined By Sensor Mode.......................................................... 12
Resetting the Master Cycle Processing ........................................................................ 13
How the Master Cycle is Defined.......................................................................... 13
Automatically Resetting the Master Processing..................................................... 13
Manually Resetting the Master Processing............................................................ 14
Starting A Follower Cycle........................................................................................... 15
Homes and the Follower Zero Position ........................................................................ 16
Indexes and the Follower Zero Position....................................................................... 16
Cycle Inter-Relationships............................................................................................ 17
Operational Timing..................................................................................................... 18
Maximum Master Velocity.......................................................................................... 19
Sensors ....................................................................................................................... 20
Selection .............................................................................................................. 20
Sensors: When, Where and Why .......................................................................... 21
Installation Guidelines 23
Attaching the PCM-22 Module ................................................................................... 23
I/O Wiring.................................................................................................................. 23
Input Wiring ........................................................................................................ 23
Output Wiring...................................................................................................... 23

PCM-22 Rotary Knife Controller
vi © EMERSON Motion Control
PCM-22 Software Setup 25
Programming the PCM-22...........................................................................................25
Master Axis .................................................................................................................29
Description ...........................................................................................................29
Master Axis Setup.................................................................................................31
Master Cycles ..............................................................................................................37
Master Cycle Number............................................................................................37
Master Cycle Length.............................................................................................37
Master Phase Distance ..........................................................................................40
Master Cycle Defined By Sensor ...........................................................................40
Follower Cycles ...........................................................................................................42
Cycle Number.......................................................................................................43
Follower Cycle Length..........................................................................................43
Cycle Defined by Registration Sensor....................................................................46
Phase Correction Limit .........................................................................................47
Phase Distance Error Limit (+) .............................................................................47
Phase Distance Error Limit (-) ..............................................................................47
Phase Correction Deadband...................................................................................48
Length Change Increment.....................................................................................48
Master Cycle Number............................................................................................48
Batch Count..........................................................................................................48
Cycle Count ..........................................................................................................49
Working Segment Width.......................................................................................49
Offset/Phase Fine Increment..................................................................................51
Offset/Phase Coarse Increment..............................................................................51
Input Functions............................................................................................................52
Description of Input Functions..............................................................................53
Typical Input Assignments....................................................................................57
Output Functions .........................................................................................................58
Description Of Output Functions...........................................................................58
Recommended Output Assignments......................................................................62
Programming...............................................................................................................63
Additional programming functions........................................................................63
Example program..................................................................................................64
Example Applications 67
Rotary Knife ................................................................................................................67
Seal and Cut Off Packages...........................................................................................68
Flexible Bag Maker......................................................................................................69
Pick and Place..............................................................................................................70
Imprinter .....................................................................................................................71
Maximizing Profile Performance 73
Commands Referenced.................................................................................................74
Minimizing Length Variation......................................................................................74
Minimizing Phase Variation........................................................................................76

P/N 400274-01 Revision A7 vii
Tips and Troubleshooting 80
General Issues............................................................................................................. 80
Product Ranges and Limits.......................................................................................... 80
Follower Cycle Will Not Start ..................................................................................... 81
Verifying the Working Segment Position .................................................................... 81
Issues Maintaining Phase............................................................................................ 82
System Calibration Issues............................................................................................ 83
Synchronization Source Issues .................................................................................... 83
Running Into a Length Limit....................................................................................... 84
Missing Sensor Issues ................................................................................................. 85
Extra Sensor Issues ..................................................................................................... 86
Common Operation Issues........................................................................................... 87
Appendix A - Serial Commands 88
CI2 - Executing Master Cycle ..................................................................................... 88
CQ - Cycle Status Query ............................................................................................. 88
FF - Follower Cycle Flags........................................................................................... 91
FM7 - Master Phase Variation In User Units............................................................... 92
FM8 - Follower Phase Variation In User Units............................................................ 92
FM9 - Master Length Variation In Sync. Counts......................................................... 92
FM10 - Follower Length Variation In Resolver Counts ............................................... 93
FM11 - Master Axis Velocity...................................................................................... 93
FM12 - Average Master Length In User Units............................................................. 93
FM13 - Average Follower Length In User Units.......................................................... 93
FM14 - Computed Starting Master Distance In Master Steps ...................................... 93
FN1 - Follower Cycles Per Follower Sensor................................................................. 94
KC4 - Total Cycle Count............................................................................................. 94
MF - Master Cycle Flags............................................................................................. 94
ML11 - Current Master Length In Master Steps .......................................................... 95
PH4 - Minimum Master Velocity For I/O Profile Adjustments .................................... 95
TC5 - Working Ratio Change Increment..................................................................... 95
Appendix B - PCX Cycle Screens to FX Command Cross
Reference 96
PCM-22 Master Cycles Screen.................................................................................... 96
PCM-22 Follower Cycles Screen................................................................................. 97
Appendix C - Master Signal Components 98
Encoder Operation...................................................................................................... 98
Encoder to Drive Cables.............................................................................................. 99
Drive to Drive Cables.................................................................................................. 99
Index 100

P/N 400274-01 Revision A7 1
Introduction
This manual provides setup and programming information for the
PCM-22 Rotary Knife Controller Application Module.
It is important that you become familiar with the 230V FX Drives Setup
and Programming Operator's Manual (P/N 400282-00), 460V FX Drives
Setup and Programming Operator's Manual (P/N 400310-00) or 525
Programmable Motion Controller Installation and Operation Manual
(P/N 400276-01) as appropriate.
This manual should be read completely before installing the
PCM-22. It provides the background information needed to setup and
configure the PCM-22/FX amplifier combination using PCX 7.x software.
Description
The PCM-22 Rotary Knife Controller is an application module that
attaches to any EMERSON Motion Control FX positioning servo drive.
The PCM-22 enables a FX drive to automatically calculate and create
motion profiles using sensor information and/or user-defined parameters.
The PCM-22 is designed to maintain a phased relationship between the
motor axis (referred to as the Follower axis) and the motion of an
independent axis (referred to as the Master axis).
SCS-4
ENCODER
FX AMPLIFIER
WITH PCM-22
MSC
CABLE
MASTER REGISTRATION
SENSOR
MOTOR
FOLLOWER
SENSOR
KNIFE
AXIS ANVIL
Figure 1Typical Application - Rotary Cut-Off.

PCM-22 Rotary Knife Controller
2© EMERSON Motion Control
The PCM-22 accepts application data relating to the mechanical
dimensions of the system entered using PCX Software. These parameters
along with sensor and synchronization information allow the PCM-22 to
calculate the motion profile necessary to meet the user specified
positioning requirements of the application.
Many parameters relating to the PCM-22 application can be changed
using hardware inputs, PCX software or serial commands. Using these
new parameters, the PCM-22 will calculate the new motion
automatically, without stopping, to maintain continuous machine
operation.
If an axis uses a registration sensor, the PCM-22 can automatically
adjust parameters based on sensor information about that axis. It will,
within user-defined limits, automatically compensate for length changes
and detected mechanical inaccuracies.
For example:
If the distance between registration sensor inputs on the Follower axis
indicate that the length is 8.25 inches and not 8.30 inches as entered
using PCX. The PCM-22 will automatically make adjustments to
compensate for the difference in length.
These capabilities allow the PCM-22 to produce one or more cycles of
motion for every individual cycle of motion produced by the Master axis.
The PCM-22 will position the Follower axis to a corresponding position
and velocity relative to the Master axis while it is executing a cycle.
This type of motion profile is commonly used in cutting, sealing, printing
and perforating applications.

Introduction
P/N 400274-01 Revision A7 3
FeaturesThe features of the PCM-22 Rotary Knife Controller include:
•Set up with easy-to-use PCX software.
•Works with all FX series drive products and 525 PMC products.
•Allows an FX drive to accurately position and match speed based on
data received from a Master axis.
•Drive setup parameters are stored in the PCM-22 module. This
allows the PCM-22 to be transferred to another FX drive of the same
size without losing any setup parameters.
•Calculates cycle profiles based on user-defined parameters
automatically.
•All parameters are in user-defined units.
•Most parameters can be changed automatically, without stopping.
•Two internal counters for each cycle: product cycle counter and
product batch counter.
•100 programs (with a maximum of 512 steps total for all programs).
•16 Master axis and 16 Follower axis motion profile definitions.
•98 user-assignable I/O functions.
•64 indexes.
•2 homes.
•Expands I/O line capacity of FX drive with an additional eight
optically isolated input lines and four optically isolated output lines.
•Interactive cycle diagnostic capabilities.
•Always uses linear ramps for Homes, Indexes, Jogs and Follower
cycles for increased accuracy.
Note: Not all of the features available with the PCM-22 will be used in
every application.
For example:
There are 15 programming functions available with the PCM-22
however, a typical rotary knife program will use only a few of
them.

PCM-22 Rotary Knife Controller
4© EMERSON Motion Control
Terminology
Master Cycle Length
The Master Cycle Length (also called the Master Length) is the
particular distance, in user units, that the Master axis (encoder or
upstream drive) moves during each Master cycle. It is the distance
between two Master Cycle zero positions. See Figures 2 and 3.
If the Master Cycle Defined By Sensor is “Yes”; when the Zero Master
Cycle sensor detects a target on the Master axis, that is the Master zero
position. The distance between two Zero Master Cycle positions is the
Master Cycle Length.
If the Master Cycle Defined By Sensor is “No”; when the first Zero
Master Cycle input is received, that is the initial Master zero position.
This will be the only Zero Master Cycle input required for all Master
cycles following. When the Master axis has moved the user entered
Master Cycle Length, it has moved the distance between two Master zero
positions.
WORKING SEGMENT
R
O
T
A
T
I
O
N
MASTER PHASE
DISTANCE
CIRCUMFERENCE OF
ROTARY KNIFE EQUALS
FOLLOWER LENGTH
ZERO
FOLLOWER
SENSOR
WORKING
OFFSET
ZERO
MASTER
SENSOR
PRODUCT
MOVEMENT
MASTER
LENGTH
PHASE CYCLE
POINT
Figure 2Typical Rotary Knife System Component Locations
Follower Cycle Length
The Follower Cycle Length (also called the Follower Length) is the
distance, in user units, that the Follower axis (PCM-22/FX drive) moves
during each Follower cycle. It is the distance between two Follower cycle
zero positions. See Figures 2 and 3.
If the Follower Cycle Defined By Sensor is “Yes”; when the Zero Follower
Cycle sensor detects a target on the Follower axis, that is the Follower
zero position. The distance between two Zero Follower Cycle positions is
the Follower Cycle Length.

Introduction
P/N 400274-01 Revision A7 5
FOLLOWER LENGTH
ONE TO ONE RELATIONSHIP (IGNORING SCALE) BETWEEN
MASTER LENGTH AND FOLLOWER LENGTH.
MASTER LENGTH
ONE
CYCLE
Figure 3Relationship Between the Master Cycle Length and the Follower Cycle Length
If the Follower Cycle Defined By Sensor is “No”; when the Follower cycle
starts, it is at the Follower zero position. When the Follower axis has
moved the user entered Follower Cycle Length, it has moved the distance
between two Follower zero positions. See Homes and the Follower Zero
Position.
Working Segment
This is called Working Segment Width on the Follower Cycles screen. It
is the constant velocity portion of the cycle, usually when the Follower is
in contact with the product. The Follower moves at the Working Ratio
velocity relative to the Master velocity during this distance. See Figures
4, 5, and Cycle Inter-Relationships, Maximum Product Velocity and
Variable Segment.
Note: The Master Length also has a Working Segment. It is not
directly user adjustable, it is computed from the Follower
Cycles Working Segment divided by the Working Ratio. See
Figure 6.
Cycle Point
The Cycle Point is at the center of the Working Segment. It is the
beginning and the end of every cycle. See Operational Timing.
Working Offset
The Working Offset is the distance from the Cycle Point to the Follower
zero position, in the direction of Follower rotation. The Follower zero
position is the same position as the Zero Follower Sensor if used. See
Figures 4, 5, Cycle Inter-Relationships, Homes and the Follower Zero
Position.

PCM-22 Rotary Knife Controller
6© EMERSON Motion Control
FOLLOWER
LENGTH
ONE TO ONE RELATIONSHIP (IGNORING SCALE) BETWEEN
MASTER LENGTH AND FOLLOWER LENGTH.
MASTER
LENGTH
ONE
CYCLE
VARIABLE SEGMENT
CYCLE POINT
WORKING
SEGMENT
WORKING OFFSET
FOLLOWER
ZERO POSITION
Figure 4Follower Terminology Relationships
B
A: FOLLOWER CYCLE LENGTH
B: FOLLOWER ZERO POSITION
C: WORKING SEGMENT
D: VARIABLE SEGMENT
E: WORKING OFFSET
F: CYCLE POINT
(CENTER OF WORKING SEGMENT)
G: CYCLE DROPOUT POSITION
G
C
D
A
F
E
DIRECTION
OF
FOLLOWER
ROTATION
Figure 5Circular View of Follower Terminology Relationships
Variable Segment
This is a computed parameter. It is the Follower Cycle Length minus the
Working Segment. This is where all cycle adjustments occur. See Figures
4, 5, 6 and Cycle Inter-Relationships.
WARNING!
When designing a PCM-22 system, the peak acceleration and the peak
velocity required during the Variable Segment must be calculated at
the maximum process speed with the shortest Master Length
spacing. This is necessary to determine the required motor size.
See Maximum Product Velocity.

Introduction
P/N 400274-01 Revision A7 7
Cycle Drop Out Position
The Cycle Drop Out Position is the position exactly opposite the Cycle
Point. While Cycle Drop Out input function is active, the Follower will
complete its current cycle and decelerate to this position and hold there.
See Figure 5, the Cycle Drop Out input function, Cycle
Inter-Relationships, Homes and the Follower Zero Position.
Working Ratio
The Working Ratio defines the relationship between the Follower
velocity and the Master velocity during the Working Segment.
For example:
If the Follower is to move the same speed as the Master during the
Working Segment, then the Working Ratio would be 1.00000. This is
common in many applications.
If the Follower is to move 5 percent faster than the Master velocity
during the Working Segment, then the Working Ratio would be 1.05000.
The range is from 0 to 9.99999.
FOLLOWER
LENGTH
ONE TO ONE RELATIONSHIP (IGNORING SCALE) BETWEEN
MASTER LENGTH AND FOLLOWER LENGTH.
MASTER
LENGTH
ONE
CYCLE
WORKING OFFSET
VARIABLE SEGMENT
CYCLE POINT
WORKING SEGMENT
WORKING RATIO
WORKING
SEGMENT
VARIABLE SEGMENT
COMPUTED RATIO
FOLLOWER
ZERO POSITION
Figure 6Follower Component Relationships to the Master Cycle Length

PCM-22 Rotary Knife Controller
8© EMERSON Motion Control
Phase A repeating pattern is called a cycle. When two repeating patterns are
synchronized there is an inherent position relationship between the two
patterns called phase. See Figure 7.
This means that:
There is a one-to-one positional profile relationship between the
two lengths (ignoring scale) and every point within the two
lengths.
ONE
CYCLE
MASTER
LENGTH
VARIABLE SEGMENT
COMPUTED RATIO
FOLLOWER
LENGTH
VARIABLE SEGMENT
CYCLE POINT
PHASE
WORKING SEGMENT
WORKING RATIO
WORKING
SEGMENT
WORKING OFFSET
FOLLOWER
ZERO POSITION
Figure 7Phase Relationship Between Master and Follower Cycle Lengths
The PCM-22 maintains the phase relationship by automatically making
adjustments based on sensor inputs and applying user-defined
parameters. Figures 3, 4 and 6 show a phase relationship of zero.
Average Length
The PCM-22 uses continuous averaging when an axis is defined by
sensor. Continuous averaging provides increased stability by
incorporating every length into the average, starting from the initial
Follower Cycle Length or Initial Master Length. Average lengths are
generated from the following equation for the Master and the Follower
axes:
(
Average Length Current *(Averaging -1)) +New
Averaging
=
Current is equal to the current average length.
New is equal to the new measured length.
Averaging is entered by the user from 1-8.

Introduction
P/N 400274-01 Revision A7 9
For example:
If eight is entered here the new average Follower Length calculated by
the PCM would be:
(
Average Length Current *7) +New
Averaging
=
It takes at least three times the averaging number of cycles on an axis to
“learn” a change in length (e.g. if the averaging is set to eight, the PCM
will need to sense at least 24 cycles to completely adjust for the new
length). See Follower Length Correction Limit and Master Length
Correction Limit.
Therefore, the lower the average the faster length errors are corrected.
However, too low a value adversely affect the drive’s ability to quickly
correct for phase errors by causing overcompensation and instability. See
Maximizing Profile Performance and Theory of Operation.
The Average Master Cycle Length and the Average Follower Cycle
Length are the learned lengths which are used only when defined by
registration sensor.

PCM-22 Rotary Knife Controller
10 © EMERSON Motion Control

P/N 400274-01 Revision A7 11
Theory of Operation
The operation of the PCM-22 is explained in the following sections.
This manual should be read completely before installing the
PCM-22.
General Running
The Master axis position is monitored by the PCM-22 using
synchronization signals. These signals, which come from an incremental
encoder driven by the Master axis or an upstream FX drive, provide the
positioning data to the PCM-22.
In order to maintain the proper phase relationship between the two axes,
the PCM-22 monitors the Zero Master Cycle and Zero Follower Cycle
sensors of both the Master and the Follower axes.
If the Follower axis does not use a sensor then the PCM-22 will use the
Follower Cycle Length parameter entered and only correct for Following
Error. Following Error is the difference between the motor’s
commanded position and it' actual position. No automatic length or
phase adjustments will be made for the Follower axis.
If the Master axis does not use a sensor, no corrections to the Follower
axis’ motion profile will be made for product differences or encoder
slippage.
If the Follower axis is not in phase synchronization with the Master axis,
the PCM-22 computes a correction which is applied in the next Follower
cycle. The Follower axis will speed up or slow down depending on what is
required for the length or phase correction. If both the Follower and the
Master axes are in phase synchronization, no correction is made.
The portion of the motion profile called the Variable Segment is where
all user changes or profile adjustments occur for each individual Master
Length. The remainder of the motion profile is called the Working
Segment. The Working Ratio will always be maintained during the
Working Segment.
Any changes made before the Cycle Point will take place during the next
cycle. If parameters are entered that cannot be accommodated while in
cycle, the Cycle Limit Reached (output function 41), if assigned, will be
activated until the cycle can be executed as defined. See Operational
Timing.
Product (master) positions are continuously tracked whether a Follower
cycle is executing or not. At power-up the PCM-22 is executing the
Master Cycle zero (0) definition. See the MF serial command.

PCM-22 Rotary Knife Controller
12 © EMERSON Motion Control
The PCM-22 handles the Master position information differently
depending on whether a product registration (master) sensor is used or
not. Each of the two ways of handling the Master position information
have different applications but operate similarly in the respect that
Mater position information is continuously tracked whether a Follower
Cycle is executing or not.
Master Cycle Defined By Sensor Mode
When a Zero Master Cycle sensor input occurs, the distance traveled
from the last product position will be checked to see if it is between the
Master Length Upper Limit and the Master Length Lower Limit. This
measured distance is factored into the Average Master Length starting
from the user entered Master Cycle Length. Any necessary corrections
will be made to the next Follower axis motion profile. See Average
Length, Master Cycles screen and Operational Timing.
FX AMPLIFIER WITH PCM-22
REGISTRATION
MARKS
FOLLOWER
AXIS
FOLLOWER
SENSOR
MASTER AXIS (SYNC ENCODER)
MASTER SENSOR
ROTARY KNIFE
Figure 8PCM-22 Rotary Knife System Example
Master Cycle Not Defined By Sensor Mode
If the Master is Not Defined By Sensor, the user entered Master Cycle
Length will be used by the PCM-22. No corrections to the Follower axis’
motion profile will be made for product or encoder slippage in this mode.