STATE OF TECHNOLOGY REPORT Motors, Drives and Motion
Transcript of STATE OF TECHNOLOGY REPORT Motors, Drives and Motion
STATE OF TECHNOLOGY REPORT
Motors, Drives and Motion
STATE OF TECHNOLOGY REPORT
Motors, Drives and Motion
eHANDBOOK
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TABLE OF CONTENTS
How do I make precision-motion machinery IIoT-ready? 6
Equipment with multiple motion applications needs to have
connectivity to the Industrial Internet of Things
Invite the drives to join the motor team 21
The best motor and drive for the application should
go together like two peas in a pod
The basics of variable frequency drive installation 25
Once a VFD is specified, pay attention to these installation
tips to realize its benefits
Keys to specifying hydraulic power systems 29
How to be fluid with the component choices that create
powerful pressure and flow
Variable data finishing system keeps pace with digital-printing technology 33
Sprint Variable Data Finishing System transforms variable
print material to finished product at 1,500 ft/min
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 3
AD INDEXAerotech . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Allied Motion . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Beckhoff Automation . . . . . . . . . . . . . . . . . . . 24
Bimba . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Bishop WisCaver . . . . . . . . . . . . . . . . . . . . . . . 31
Festo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Fraba . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
KEB America . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Without motors, motion systems and drives, many machines won’t work . And,
to get the work done properly, there are basics to understand beyond the
simple single-speed motor application . There is much to consider—including
how components must be installed properly—when specifying and designing systems to use
motors and drives .
Rotary motion devices are moving beyond the machine to the Industrial Internet of Things,
as well . This report highlights best practices to follow for precision motion on new and
future OEM equipment . Hydraulic power systems are also creating motion today, and they
need motors . Digital-printing technology is also taking advantage of motors, motion and
drives to create industrial-strength finishing systems .
This State of Technology Report brings together expert advice related to trends in motors,
motion and drives . The basics of motor and drive selection and variable-speed-drive instal-
lation are included, as well . We hope you find this useful .
Get machines moving with motors, motion and drives
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 4
© Copyright 2016 Bimba Manufacturing Company. All Rights Reserved.
PNEUMATIC I HYDRAULIC I ELECTRIC
FOR EVERY ELECTRIC MOTION APPLICATION, INCLUDING HEAVY DUTY, THERE’S A PROVEN BIMBA SOLUTION
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ROD STYLES • Lead and ball screws • Guided for side loads • High thrust options • Handles loads up to 40,000 lbs
COORDINATED MOTION • Unique continuous belt provides coordinated motion for each axis • Stationary motor reduces weight of the carried axis • Ideal for high speed pick and place applications
RODLESS • Belt – up to an astounding 85 ft • Ball screw – high effi ciency • Lead screw – economical
RACK & PINION • Vertical loads • High thrust with linear guide rail
LINEAR SERVO• High speed – up to 180 in./sec., with accelerations reaching 5G• Extreme precision – up to 1 micron• Dual-rail comes standard
MOTORS & DRIVES • Stepper – AC & DC• Servo – AC & DC• IntelliMotor® – control, encoder, motor, I/O, communication• AC & DC controllers• DC drives
ELECTRICMOTION
ROD STYLES • • • • to 40,000 lbs
COORDINATED
Unique continuous belt provides coordinated motion for each axis
Stationary motor reduces weight
pick and place applications
Guided for side loads High thrust options Handles loads up
to 40,000 lbs
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A Control Design reader asks: I work for an OEM, and we are developing new equip-
ment that requires multiple motion applications on one machine . This includes
master-follower rollers, tension control, unwind, wind, variable speed conveyors,
a precision three-axis gantry and automatic changeover position adjustments . It covers the
full range of motion control from simple ac induction motors to stepper motors and preci-
sion servo control .
Our sales department wants to sell this new OEM equipment as the latest technology in-
cluding the buzzwords “precision motion” and “IoT-ready features .” With all the different
motion-control requirements on the equipment, do I mix and match the best motor, stepper
or servo for each axis, or do I just use servos on every axis? Along the same lines, should I
stick with a single controller or distribute the motion control? I’m looking for best-practices
in motion control for this new and future OEM equipment .
ANSWERS
How do I make precision-motion machinery IIoT-ready?Equipment with multiple motion applications needs to have
connectivity to the Industrial Internet of Things .
By Mike Bacidore, editor in chief
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 6
SINGLE PLATFORMPrecision motion control can be defined by
network update rate, positioning accuracy,
throughput and drive loop closure rates,
plus the functionalities listed and safe mo-
tion capabilities .
IoT-readiness means supporting standards
needed to communicate with the cloud,
such as OPC-UA and Ethernet, but we are
still defining the architecture in the Indus-
trial Internet Consortium (IIC) and the IIC’s
eHANDBOOK: Motors, Motion & Drives 7
Smart Factory Task Group, so it would be a stretch to call
machinery IoT-ready .
For control, definitely use a single control platform . Syn-
chronizing motion between multiple controllers costs en-
gineering effort, money (hardware and software licenses),
performance (time used to communicate between control-
lers), space and wiring . One program developed in one
software-development environment should run on one pro-
cessor on one controller on one network cable to run HMI,
motion, I/O, PLC, robots, safety, condition and energy moni-
toring . The technology is there today, all standards-based .
When deciding between servo and stepper and VFD, there
are two schools of thought . You can spend a little more, and
standardize on servos to reduce maintenance inventory and
increase performance, but more likely you will use a mix of
servo and VFD and quite possibly steppers, which have got-
ten more controllable and can be very cost-competitive .
For example, a manufacturer of palletizers offers two op-
tions, both using the same inverter drives and software
function blocks that can run both servo motors and induc-
tion motors . The motors replace pneumatics completely,
so they differentiate as the only all-electric palletizer . For
customer that require higher performance, they have an
all-servo option where the induction motors are replaced by
servos (same drive rack, same controller) .
—John Kowal, director, business development, B&R Industrial Automation,
www .br-automation .com
CENTRALIZED CONTROLAs you work on a motion control solution for a complex
machine, you should break down the machine into the
mechanical structure . Following the mechanical structure
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of your machine, define each part of the machine, such as
infeed, different functionalities of the machine and outfeed .
If all of the mechanical modules are defined, you can use
technology modules to realize the single application parts .
This is a typical controller-based solution . The controller, as
the brain of the machine, controls everything using technol-
ogy modules . If most of your machine’s axes are servo axes,
it’s best to use only servo axes . But a one-drive solution is
able to run a standard motor or a servo motor .
When you have a controller-based solution with technol-
ogy modules, machine information is centralized in one
place . The controller can be connected to the Internet and
the cloud, giving you the necessary machine information,
allowing you to meet your IoT requirements .
—Daniel Repp, business development manager of automation solutions,
Lenze Americas, www .lenze .com
PROS VS. CONSToday in automation, there is no concept more popular than
the Internet of Things . The underlying idea, of course, is that
we are moving toward architectures made by components
(drives, sensors) that are smart and connected enough to
run independent functionalities, such as energy manage-
ment, self-diagnostics and email notification . At this point
though, there are very few hardware components available
that have that level of brain and certainly not enough of
them to cover an entire complex architecture .
PLCs, motion controllers, and industrial PCs (IPCs) are still
the parts of the machine that collect data, run diagnostics
and connect with the outside world for analysis, service and
maintenance . As per how to implement the control system in
a complex machine, there are two different approaches—cen-
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eHANDBOOK: Motors, Motion & Drives 9
tralized architectures and decentralized architectures—both
with pros and cons .
Centralized: Typically run by an IPC or a powerful motion
controller, it’s an architecture with only one controller
running the entire system managing motion control, the
logic control and the process control elements .
Pros:
• one controller (reduced upfront cost)
• one program (all the variables and the information are at
hand in the same program) .
Cons:
• program complexity (the code has to take care of every-
thing)
• loss of modularity (adding or removing parts of the ma-
chine requires severe changes of the code) .
Decentralized: Typically run by a process PLC or an IPC as
supervisor, the different functionalities of the architecture
become modules with each one handled by a local control-
ler (motion controller or PLC, depending of the task) .
Pros:
• local programs are easier to write, maintain and troubleshoot
• modules are easier to build, wire and service
• more IoT-like architecture (not many smart components,
but smart modules) .
Cons:
• each module needs a controller (higher upfront costs)
• each module controller needs to exchange information
with the supervisor controller (more coding to ensure
proper communication and variable exchange) .
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Regardless of the architecture chosen,
there are a few best practices that would
offer advantages to an OEM developing
complex architectures .
• Use programming software which includes
PLC and HMI programming and drives
commissioning in one package . This will
reduce the development of the software
aspect and will focus the maintenance and
service crews to a single platform .
• Where possible, use a single vendor that
can provide the whole solution . This will
minimize the time and the hassle of mak-
ing the different hardware components
talk to the controller(s) .
• If there are reasons to not select one
vendor for everything (end-user specifica-
tion or specific functionality requirements
not available from that vendor offer), pick
vendors that offer hardware open to third-
party equipment, possibly with libraries
and/or programming examples that can
be provided .
—Simone Gianotti, motion product manager, Schneider
Electric, www .schneider-electric .us
PNEUMATIC POSITIONINGDependent on the application, pneumatic
positioning and motion control could be
used as an alternative . This may provide a
better return on investment versus preci-
sion stepper controls with a lower price
point to the market, especially in areas
requiring washdown and IP-rated products .
Many operations performed in automa-
tion are very well suited for pneumatics,
often involving repetitive fast-moving tasks
that involve linear and/or rotational mo-
tion . Pneumatics can offer 100% duty cycle
without heat buildup when compared to
some electrical solutions and offer condition
monitoring providing IoT-ready features
such as valve-level diagnostics and condi-
tion monitoring solutions .
—Mark Densley, head of product management—con-
trols, Aventics, www .aventics .com/us
BALANCE COST AND PERFORMANCEThere is a difference between what a sales
department asks for and what it can sell .
Machine designers and engineers are con-
stantly tasked with the job of balancing cost
with performance . Deciding to select all
servos and the highest-performing control
is often not the best choice .
Regarding the controller, I would recom-
mend using an embedded control or in-
dustrial PC (IPC) where you can . Create
modular, brand-free code; use existing
motion function blocks; and implement a
synchronized motion fieldbus such as Ether-
CAT . Using an embedded subcontroller for
the three-axis gantry would simplify your
overall machine control, but distributing the
controllers further may simply add cost to
your machine .
Servos are not always the best choice
in motor technology . AC motors and
drives perform well where the rotor iner-
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 10
tia doesn’t hinder performance, such as
conveyors, master-followers and tension
systems . Servos are typically the best
performers on robots and high-speed
gantry systems, where their high torque-
to-inertia ratio really shines . However, if
the gantry system is large, then servos
lose their dynamic edge and ac motors
meet the need . Small, subfractional hp
applications can utilize stepper systems .
In any case, choose a drive system that
can be linked to the motion fieldbus . You
will reduce machine wiring, ease motion
control, improve machine troubleshooting,
gain data collection and improve machine
serviceability . Connected drives can be
programmed automatically and are reach-
able via remote access .
Don’t forget remote access . Customers
expect fast responses when something
goes wrong . Using a secure, reliable re-
mote device will pay for itself with the
first trouble call .
—Scott Cunningham, engineering manager, KEB Ameri-
ca, www .kebamerica .com
FROM SIMPLE TO COMPLEXThe newest product lines on the market
offer controller platforms and flexible
multi-axis systems that perform both com-
plex and simple automation and motion
control tasks . When a multi-axis system is
required, customers can look to modular
VFDs (Figure 1) . These modular systems
have the ability to handle precision servo
control and master-slave functions, as well
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 11
MULTI-AXISFigure 1: When a multi-axis system is required, customers can look to modular VFDs.
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 12
as controlling simple applications such as
variable-speed conveyors, tension control
and winding applications . With the ability
to run synchronous or asynchronous mo-
tors with or without encoder feedback, it
isn’t necessary to purchase servos for every
axis . State-of-the-art features like this allow
customers to be cost-effective with their
motor selections, while ensuring a perfect
solution for their applications . When it
comes to deciding on how many controllers
to use, companies make it simple, providing
powerful controllers with high performance
that can handle several axes, eliminating the
need for several controllers on a single ma-
chine . With some of these advanced con-
trollers, you can choose from a wide range
of application modules, from positioning, to
robotics, that are simply configured and re-
quire no programming experience . For the
advanced user, a fully operational program-
ming environment that allows the user to
program the machine exactly as they see fit
is available .
—Jason Oakley, electronics product/application engi-
neer, SEW-Eurodrive, www .seweurodrive .com
FLEXIBILITY IS VITALBased on the application and functions
described, the OEM would ideally use a
control platform that has open interfaces to
third-party automation products (RF sen-
sors, vision systems, glue or heater con-
trols) . The control needs to be capable of
interfacing with all of the mentioned motor
technologies (Figure 2) .
The control the reader ultimately chooses
should offer functional libraries already
developed for robotic and winding/tension
functions, so that he or she will not have to
create them from scratch . For winding con-
trol, as an example, and robotics, the OEM
can simply choose from pre-engineered
libraries and/or function blocks, and thus
will not have to reinvent the wheel . The
engineering time savings are considerable,
eliminating much of the usual additional cal-
culations and math needed for these types
of motion segments .
CONTROL CAPABILITIESFigure 2: New capabilities in today’s control allow machine builders to develop all-new, customer-specific ways to interact with, monitor and manage their machines, including mobile-device based interfaces.
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 13
To answer the reader’s question about single
vs . distributed control, what it really comes
down to is how the OEM’s machinery is ulti-
mately sold . One control can certainly handle
all of the functions described; however, if the
OEM offers individual elements of the ma-
chine for sale separately, it may be of benefit
to offer the machine with multiple controls .
To help this OEM’s sales organization, the
most important technology choice for
precision motion will be in the drive tech-
nology chosen . Clearly, servo motion is the
most precise for critical motion elements in
the machine .
As for IoT-readiness, this can mean a lot of
things . What will be important for the OEM’s
sales team is to help end users of their ma-
chines to understand how the IoT benefits
them specifically . In the type of application
described by the reader, IoT-ready typically
means machine connectivity paired with
good data analytics—in other words, IT func-
tions bridged out of the control to another
system . Technology can connect to the
cloud, display key information visually via
mobile devices, synchronize machine data
with management and decision-oriented
dashboards and provide predictive mainte-
nance elements . These capabilities offer a lot
of flexibility to end-user customers—flexibil-
ity, which is vital, because every company’s
IoT needs are very specific and individual .
—Dave Cameron, director of sales, electric, drives & con-
trols, Bosch Rexroth, www .boschrexroth-us .com
REAL-TIME CONTROLPrecision motion is much simpler to achieve
today than it was just seven or eight years
ago . One reason for this is that controls
engineers have embraced real-time con-
trol systems and real-time fieldbuses such
as EtherCAT . This provides the ability to
retrieve actual and setpoint positions on
the fly without interrupting data through-
put, as can happen with other fieldbuses .
Advanced functionality, such as distributed
clocks, provides highly precise timestamps
on measured values and events that oc-
cur in the overall system . On the heels of
this movement, drive vendors and encoder
vendors have begun to standardize on the
same real-time fieldbuses . When using a
fieldbus that has the same precise time
base, external encoders can be used that
might deliver higher resolution than the
encoder already on the servo motor in the
application . Today, manufacturers have
increased the capabilities of servo encoders
to feature higher resolution, and, as a result,
drives are easier to configure to the refer-
ence external feedback . The precise veri-
fication of a position leads to much more
precise motion control overall .
IoT concepts have already entered the realm
of machine control, enabling access to larger
amounts of highly accurate data for analysis .
This is the biggest reason why IoT is now
being accepted into motion applications .
Motion-related data, such as axis torque or
velocity, can be stored for viewing in dash-
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 14
boards that help users to understand events
as they happen . This includes events that are
predicted and those that aren’t . Fortunately,
the high costs of third-party IoT hardware
and software can be eliminated in PC-based
control applications . PC control adds further
benefits through the use of open, proven
protocols for cloud communication such as
MQTT or AMQP . Accessing this data, wheth-
er locally or remotely through a secure,
cloud-based message broker, becomes very
easy with system-integrated solutions .
With all the different motion-control require-
ments on the equipment, do I mix and match
the best motor, stepper or servo for each
axis, or do I just use servos on every axis?
When you work with a motor vendor, they
will provide a number of viable options for
your application . However, your knowl-
edge of the exact system mechanics is far
greater than that of the vendor, so you
should also use a motion designer tool or
other sizing software that can be adjusted
to your application .
The cost and size of servo-motor technol-
ogy and drive systems are continually de-
creasing, enabling the use of servo motors
in more cost-sensitive applications . Power
stages that can handle capacitive and re-
generative energy have also helped to cut
costs . Stepper technology on the drive side
has improved dramatically, extending the
life of the motor and drive, while narrow-
ing the performance gap with some servo
solutions . Current controller optimization
facilitates performance increases, enabling
the use of steppers in motion applications
ADJUSTABLEFigure 3: Conveyor systems are often seen as more basic elements of a machine, but, if you need a vertical conveyor or a conveyor with a tensioner or counterbalance weight, software with the ability to easily make adjustments upfront in the design process is incredibly valuable.
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 15
without fixed speeds and repetitive motion
profiles . With the need for technological
advancement on one side and the need for
cost reductions on the other, a platform
that enables flexible hardware changes
is critical in cases where a stepper motor
needs to be switched out for a servo motor,
for example . The principle of abstraction
inherent to a PC-based control system fa-
cilitates reduced rework on the application
programming side, boosting flexibility and
code reusability .
Conveyor systems, for example, are often
seen as more basic elements of a machine .
However, if you need a vertical conveyor or
a conveyor with a tensioner or counterbal-
ance weight, software with the ability to
make adjustments upfront in the design pro-
cess is incredibly valuable . This can also help
you to determine where servos or steppers
are more appropriate on specific parts of a
machine, from simple to complex (Figure 3) .
Motion profiles are necessary to fully un-
derstand the motion requirements of the
application, specifically if the load or forces
on that load change as it moves or if a
complex motion profile needs to be creat-
ed for the application . The ability to enter
engineering equations for automatic calcu-
lation makes it easy to realize exact accel-
eration and torque requirements for the full
range of the application . This also helps to
verify that a chosen motor will work for the
application (Figure 4) .
Real-time fieldbuses, when paired with the
higher-end processors found in PC-based
controllers, enable efficient motion-system
MOTION PROFILEFigure 4: The ability to enter engineering equations for automatic calculation makes it easy to realize exact acceleration and torque requirements for the full range of the application.
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 16
design in a single, unified platform . Even if
this performance isn’t required for the appli-
cation, a system that can be synchronized
with an external controller is necessary to
avoid complex synchronization . Note that
some industrial Ethernet fieldbuses used for
motion require special switches and hubs,
which add cost and setup time . They can
also hinder OEMs from making their appli-
cations better than, or even simply keeping
up with, competing machine builders . Ether-
CAT is an example of a protocol that can be
used as the complete motion system bus
and does not require switches, managed or
otherwise . A final important aspect to con-
sider is industry trends . As more manufac-
turers of servo, stepper and vector drives
support fieldbuses like EtherCAT, it indi-
cates real traction and acceptance, enabling
integration by machine builders without
fear of obsolescence or nonconformance .
—Matt Prellwitz, drive technology application specialist,
Beckhoff Automation, www .beckhoffautomation .com
SEAMLESS INTEGRATIONWe receive frequent requests from OEMs
looking to integrate multiple disciplines of
control: PLCs for logic control; robot con-
trol for loading, unloading, assembly and
inspection; motion control for printing,
converting, assembly and packaging opera-
tions including winding, tension control and
registration; and CNC control for cutting,
drilling and other machining operations . Of
course, with so many complex operations
occurring in one machine, it’s critical that
all of these processes share data to ensure
that the equipment is running optimally .
This need for visibility is the origin of the
IoT-ready movement . We have a concept
we call e-F@ctory, which allows seamless
integration from ERP and MES down to indi-
vidual components within a machine on the
shop floor . We developed this technology
to optimize our own factory productivity
and efficiency, and now our customers can
benefit from this off-the-shelf IoT solution .
At the heart of e-F@ctory, the platform in-
tegrates PLC control, motion control, robot
control and CNC control all on one control-
ler . In your example, a motion CPU would
handle the tension control, unwind, wind
and conveyors, as well as the gantry and
automatic changeover adjustments . The
PLC CPU would manage the machine se-
quence, I/O and communications with other
equipment . The MES interface module al-
lows a direct connection to the MES’s data-
base without additional PCs or middleware .
This can be used for fetching jobs from the
server, downloading recipes, automatically
configuring product changeover adjust-
ments and reporting of production statistics
and traceability data, all without clipboards,
memory sticks or manual data entry .
We prefer to use servos and VFDs, rather
than stepper drives, for one simple reason:
data collection . For axes that require po-
sitioning, there is no substitute for a servo
drive and motor to ensure positioning
accuracy with closed-loop feedback . The
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 17
servo motor’s encoder position is continu-
ously monitored by the servo drive and the
motion controller . This, as well as other data
including velocity, torque, load inertia and
real-time energy consumption, is available
for monitoring and improving your process .
Stepper motors, on the other hand, are an
open-loop system . Position commands are
sent to the stepper drive, but, unless an
encoder is used, you can only hope that
the motor reached its target position and
has not been nudged out of position later .
The stepper drive and motor also consume
a considerable amount of energy . A small
investment in upgrading servo drives and
motors upfront gives you seamless visibility
into your process, reduced energy con-
sumption and motion precision and speed
that steppers can’t match .
Variable-frequency drives are a cost-
effective way of operating conveyors and
other velocity-control operations, with
significant energy savings compared to
motor starters . Variable-frequency drives
also provide extensive options for energy
saving and process monitoring, for an
easy IoT implementation .
You don’t have to choose between the
complexity of integrating multiple distrib-
uted controllers or trying to fit a complex
machine in a single CPU . You can mix PLC,
motion, robot and CNC CPUs on one con-
troller to get the best of both worlds: the
best tools for the job with the ease of a
single controller . These features translate
directly into selling points that differenti-
ate your equipment from your competitors .
Your system has the precise motion and IoT
features your sales department and custom-
ers want, with an easy-to-integrate solution
your engineers will appreciate .
—Bryan Knight, product manager & automa-
tion solutions team leader, Mitsubishi Electric,
us .mitsubishielectric .com/fa/en
ALL-SERVO SOLUTIONThere is no one answer that will fit all ma-
chines and in many cases different imple-
mentations of the same machine type will
call for different solutions given the specif-
ics of the implementation . The key factors
will be cost, performance, ease of connect-
ing various products together in the control
system and experience of the user with the
various technologies .
One solution mentioned, an all-servo solu-
tion, will have benefits for many applications .
• High-bandwidth precision motion results
in higher-quality product and through-
put in printing, converting and packag-
ing applications .
• Use of a common high-performance mo-
tion bus such as EtherCAT with software
in the machine controller reduces system
integration time .
• With the motion bus, the machine devel-
oper has the flexibility to integrate servo
drives, stepper drives, safety devices
and other third-party devices . Given the
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 18
popularity of a motion bus like Ether-
CAT, there are hundreds of automation
products that support this network that
could be integrated into the machine
control system .
• All the EtherCAT devices connect to
a central controller for a streamlined
machine-control system . If a decentral-
ized system is preferred, multiple con-
trollers can be used that communicate
with each other .
• The motion bus is structured for passing
information such as command and recipe
information to the devices or diagnos-
tic and status information to the central
controller .
• Servo drives can be connected together
to transfer power from a regenerating axis
to a generating axis, thus preventing the
need for external heat generating power-
regeneration resistors .
• Servo drives offer a variety of feedback
devices to optimized position accuracy,
cost goals and ruggedness level that the
application requires .
• In machines with multi-axis gantry, the
controller and servo-drive motion can co-
ordinate motion between multiple drives to
provide the dynamic motion compensation
needed for proper gantry motion control .
• Servo motors come in multiple types, al-
lowing optimization for each motor on the
machine: traditional tube-type motors to
direct-drive rotary or linear motors where
extremely high precision and dynamic
response are required .
The controller utilized in the system can
also integrate into the system non-servo
motors, such as steppers and VF ac driven
induction motors, where all the perfor-
mance of a servo is not required or where
cost is the main design factor or a high-
horsepower motor is needed . As mentioned,
the EtherCAT network makes integration
easier and facilitates the same wide range
of information that can be shared .
—Carroll Wontrop, senior system engineer, Kollmorgen,
www .kollmorgen .com
SIMULATED CONTROLIt is most logical to use an appropriate
type of motor to match the application re-
quirement, based on the intent of the ma-
chine part it is used with . Therefore, having
multiple types of motors, as well as sources
of power, is a common scenario . There is
a lot of literature available about central-
ized vs . distributed control that can guide
the reader on this decision . However, one
can easily understand the reader’s dilemma
in making the architectural decisions for
a fairly complex piece of equipment . This
is where simulation can play a big role .
Simulating the machine behavior, as well
as the control system, can be a great way
to assess various system architectures and
control system behavior . A case study from
Tetra Pak showcases the use of simulation
systems for machine design (www .contr-
oldesign .com/dspace) .
—Jace Allen, lead technical specialist—simulation & test
systems, dSpace, www .dspaceinc .com
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 19
SYNCHRONOUS SERVOGiven the cost point and functionality of
current synchronous servo motors and re-
spective control, we would suggest consid-
ering a design based on synchronous servo
motors wherever possible . The only excep-
tion would be where the power require-
ment is large, say 20 kW or greater; in these
cases, an asynchronous servo motor may fit
the application better . However, a drive sys-
tem that can be configured for either motor
type should always be considered .
A centralized motion control platform
seems to offer more benefits from program-
ming and support and ease of use . Only in
the case of a modular hardware require-
ment would a decentralized control system
be the preferred choice .
—William Gilbert, converting market manager, Siemens
Industry, www .siemens .com
Automation Controller
Ethernet Connectivity
Vision
Intelligent Drives
Custom Software
Advanced Control
Algorithms
Custom Motor Design
Intelligent Drives
Bring Your Machine To Life With Custom MotorsAerotech can partner with you to design a custom motor optimized for your specifi c application at a minimized price. In our concept machine above, the legs utilize both rotary and linear motion requiring special motor designs. For both the rotary and linear motion, we would customize the motor’s mechanical characteristics (torque/force, length, width, height) as well as the electrical characteristics (bus voltage, resistance, inductance, pole pitch, and current) required for the application. Aerotech can accommodate your custom motor requirements even for low-volume projects. If you have an application requiring minor customization, major customization, or a completely new motor design, contact Aerotech today.
Contact our Control Systems Group at 412-967-6839 or [email protected] to discuss your application today, or see go.aerotech.com/csg82
Hardware • Software • Firmware • Packaging • Motors • HMI • Electronics • I/OWe customize Aerotech automation for you
The Americas • Europe • Asia-Pacifi cGlobal sales, service, and support
Dedicated to theScience of Motion
AF1114M-CSG-Bring Your Machines To Life-Motors-7_875x10_5.indd 1 3/30/2017 1:24:05 PM
When your industrial motor requirements move beyond a single-speed applica-
tion to a variable-speed application with adjustable acceleration and decelera-
tion, and possibly precision position or torque control, the motor and drive
need to team up for a winning solution .
The motor drives connect to and provide enhanced operation to dozens of different types
of motors . These include dc, ac, stepper and servo motors . There are definitions to be found
online along with the advantages and disadvantages of each type of motor . However, a big
thing to keep in mind is that many of the motors are designed for a specific application or
their applications are limited .
There are also many characteristics to know when it comes to motor selection . This includes
things such as when a dc motor’s speed is high, its torque is low and vise versa . Another
characteristic is that running an ac motor slower using a variable frequency drive (VFD) is
a common way to save energy when operating fans, pumps or similar devices . Another is
that the stepper motor typically has maximum torque at zero speed, and the servo motor is
known for its dynamic speed control and precision position and torque control .
Fortunately today automation vendors have a wide selection of motors and drives for just
about any application . If you need a motor and drive, get with a local industrial distributor
or motor manufacturer . Leveraging their knowledge is often the best option .
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 21
Invite the drives to join the motor teamThe best motor and drive for the application should go together like two peas in a pod .
By Dave Perkon, technical editor
ADD THE DRIVEWith the motor selected, a matching drive
is often required . All drives typically al-
low adjustment of minimum and maximum
speed, current (torque) limit and accelera-
tion and deceleration time .
In addition to these adjustments, the dc
drive converts ac power to dc power and
regulates the armature current and voltage
to control the torque and speed of the dc
motor . The nonregenerative dc drive oper-
ates the motor in one direction only and
requires reversing the armature leads to
change motor direction . The regenerative
dc drive can reverse the motor internally
and provide a regenerative breaking func-
tion . This is important in applications that
start and stop or change directions often .
The ac drive also converts ac power to
dc power but then inverts it back to a
controlled voltage and frequency that is
output to the ac motor . The pulse width
modulated (PWM) drive is the most com-
mon ac drive and most popular of all
drives . It works well for most industrial ap-
plications due to its performance, simple
design and low cost . It converts the ac
source to dc and then inverts the dc to
an approximation of a sine wave at the
desired Volts/frequency ratio . These PWM
ac drives operate common three-phase ac
induction motors for a low-maintenance
and low-cost design .
A higher-performance ac drive is a vector
drive . It also uses PWM but can individually
control the motor speed and torque . Encod-
ers can be added to ac drives closing the
loop for improved speed regulation . Adding
an encoder to a vector drive enables 100%
or more of the rated ac motor torque to be
available at zero speed, which is desirable
when holding a load in a crane application .
The most dynamic and precise motor and
drive applications include the stepper and
servo motor paired with the appropriate
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eHANDBOOK: Motors, Motion & Drives 22
The motor drives connect to and provide enhanced operation to dozens of different
types of motors .
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 23
drive . The stepper motor and drive provide
precise position or speed control modes
whether open or closed loop . The closed-
loop servo motor and drive add a torque
control mode .
While most drives are controlled using
analog, step and direction signals or the
drives built-in indexer function, many drives
now offer various communication methods .
Some only offer configuration and monitor-
ing via this communication link; other drives
provide real-time control, coordinated mo-
tion and safety functions integrated with
the controller .
Which motor do you use, and how do you
size it? That may be a question beyond the
basics, but before you contact the vendor,
be sure to have some application informa-
tion available .
The vendor will need to know about the ap-
plication and will ask for speed, torque and
inertia information . You’ll need to know how
fast you want to run the system . The iner-
tia needed can be difficult to calculate and
requires rotational mass and radius mea-
surements, gearbox information and me-
chanical linkage configuration . The vendor
is going to ask lots of questions and then
use a software package to calculate the in-
ertia . Other variables may include load, duty
cycle, environment and positional accuracy
requirements .
The speed, torque and inertia are important,
but a defined motion profile is, as well . If a
motor application must run a wide range
of speeds with a varying load, what motor
would work best? If you can provide the ap-
plication engineer the motion profile infor-
mation, you may find that an ac induction
motor is not the best option, since a perma-
nent magnet dc motor can be more efficient
over a wide range of speeds and loads .
How complex is your motor and drive
application? Are you an OEM where cost
matters most or possibly a custom machine
builder where high performance is king? In
either case, you will need to study up on the
basics because there are many motors and
drives available . And get with you motor or
motion-control vendors during the motor
and drive selection process . They will help
find the best technology, motor and drive
for the application and address require-
ments such as motor efficiency, safety,
performance and cost .
Starting and stopping a motor can be done with three common methods: a motor
starter, soft start or variable frequency drive (VFD) . As of late, the use of a VFD is
becoming more popular than ever due to its claimed efficiency benefits, but be sure
it is needed . And, once specified, it must be properly installed to ensure reliable operation .
To start, take a step back and be sure you need a VFD for the application, as many users
don’t realize real benefits . Do you need to vary the speed of the motor or change the
motor’s acceleration? If neither, a motor starter is simple and will work great . Just want
to soften the motor starts? Consider a soft starter . For all the above, a VFD may be the
best choice .
The VFD, often called an ac drive or inverter, takes a single- or three-phase signal and var-
ies the speed of a three-phase ac induction motor . This is its main benefit . Running a motor
more slowly can save significant energy, and speed changes may be useful to the applica-
tion . Another big benefit is adjustable acceleration and deceleration . Less acceleration can
soften the mechanical forces at motor start and reduce inrush current . The VFD also has
built-in overload protection and motor start/stop control functions .
The basics of variable frequency drive installationOnce a VFD is specified, pay attention to these installation tips to realize its benefits .
By Dave Perkon, technical editor
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 25
There are both physical and electrical
installation basics to be aware of when us-
ing a VFD . When mounting the VFD on a
back panel, be sure to check the specifica-
tions . It is common for multiple devices to
be installed in one location, but all VFDs
need proper air flow, so check the installa-
tion instructions carefully when laying out
a control panel . Mount the drives vertically .
Some drives can be mounted with no clear-
ance, but it’s common to have a minimum
side-to-side spacing of 50 mm or more and
to have vertical clearance above and below
the drive of 100 mm to 150 mm .
It’s not uncommon to hear about noise
problems in VFD applications . However,
proper shielding and grounding and the use
of filters or line reactors can help . If mul-
tiple VFDs are installed in a single location,
don’t daisy-chain the ground wire; it creates
ground loops . Connect each ground to a
single ground point, connected in parallel .
The line reactor can help to protect from
transient voltages and reduce harmonics to
or from the drive . Keeping the load-side—
output—wiring less than 75 ft between the
drive and motor, or using a load-side reac-
tor, can help to reduce the potential insulat-
ed-gate bipolar transistor (IGBT) reflective
wave damage .
Electrically, proper run/stop control of
the VFD is important . Many manufactur-
ers do not recommend using contactors
or disconnect switches on the line or load
side of a VFD for run/stop control of the
ac drive and motor, except for emergency
situations . Opening a contactor at the line
or load side of a VFD while the motor is
running can cause failures in the inverter
section of the drive or reduce its life . Even
if it doesn’t cause failure, it can take sev-
eral seconds for a VFD to power on once
power is applied .
A VFD is typically controlled via start/stop
digital inputs and a speed-control signal,
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eHANDBOOK: Motors, Motion & Drives 26
Although a standard three-phase induction motor works with a VFD, a three-phase
inverter duty motor should be used .
using a 0-10 Vdc, 4-20 mA or potentiom-
eter analog input signal or a speed preset
programmed into the drive . However, a
proper risk assessment will likely show a
safe-stop function is required as well . This
functional safety capability, often called
safe torque off (STO), as defined by EN IEC
61800-5-2, is an option on many VFDs that
should be specified .
With any motor control circuit, proper
overcurrent and ground-fault protection
is required at the input of the device . A
typical VFD accepts single-phase volt-
age, but it is not intended for use with
single-phase motors . Although a standard
three-phase induction motor works with
a VFD, a three-phase inverter duty motor
should be used . The inverter duty motor
is more energy efficient when used with a
VFD . It is also not susceptible to overheat-
ing at low motor speeds and has more
low-speed torque compared to a standard
induction motor .
There are two basic types of VFDs: the
original scalar control type and the newer
vector control type . The scalar control
is open-loop using a voltage-frequency
ratio and although it provides great speed
regulation, ~0 .5%, it does not have a fast
response nor is it very precise . The vector
control can be open- or closed-loop and
uses current control of two vectors, torque
and magnetizing flux for more responsive
and precise control of the motor .
There are many more factors, features and
functions to consider when using a VFD,
so study the catalogs and manuals and
then get with your vendors . With constant-
torque or constant-speed applications,
such as conveyors, compressors or mixers,
there may be simpler options . However,
whether replacing a dc motor or varying
the speed and acceleration of your con-
veyor, fan, blower or pump, go with the
VFD option . It’s often the best choice, if
installed properly .
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 27
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Keys to specifying hydraulic power systemsHow to be fluid with the component choices that create powerful pressure and flow .
By Tom Stevic, contributing editor
When specifying a hydraulic power system, a careful analysis of the application
is required before selecting the various equipment . An open-loop hydraulic
power unit is used to supply fluid power to various hydraulic actuators such as
cylinders, rams and fixed-speed motors . Its pump typically runs at a constant speed produc-
ing a fixed fluid pressure to the system’s control valves . If no motion is demanded by the
valves and actuators, the fluid is returned to a holding tank .
When specifying the hydraulic power unit, the maximum working flows and pressures must
be defined before sizing components . The volume of fluid flow used in normal machine oper-
ation depends on of the number and types of cylinders, motors and transmissions in simulta-
neous operation at the required operational speed . The pressure is determined by calculating
the necessary force needed to perform the designed operations of each actuator . The fluid
flow necessary to meet system speed requirements must also be calculated . Many calculators
and formulas are available on the Internet and in books dedicated to the subject .
Several types of pumps may be considered . These pump types can range from simple
rotational gear pumps to more sophisticated bent axis pumps . The style of pump is
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 29
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 30
primarily determined by the required flow
and pressure . System actuators and the
desired operation of the actuators dictate
if a variable displacement device is re-
quired . The rotary gear pump style is the
most common type of pump in use . The
simple design leads to a rugged, cost-ef-
fective component that should offer many
years of trouble-free operation .
Pump mounting locations are most often
near the fluid reservoir . A top mounted
pump allows for easier maintenance access .
However, it also requires the pump to lift
the fluid with suction before pressurizing it
and may involve considerable labor to gain
access to the interior of the tank for clean-
ing purposes . Some alternative pump loca-
tions can be alongside the tank reservoir
where the pump inlet is below the minimum
fluid level and below the tank reservoir to
assure the pump is never starved for fluid .
ISO 4413 is the main industry standard de-
scribing best practices of design for hydrau-
lic systems . The standard defines several
roles for the reservoir (tank) . The tank must
dissipate the heat generated during normal
operations unless other temperature con-
trol methods are employed such as a heat
exchanger . Obviously, the tank should be
able to hold all of the system fluid under
normal system operation while maintaining
sufficient levels to avoid starving the pump .
There must be adequate room for ther-
mal expansion . The returning fluid should
be slowed to allow the release of trapped
air and for contaminates to settle . Some
method of separation between the incom-
ing fluid and the pump intake should be
provided, as with baffles or tank geography .
Some method of access for cleaning should
be made available .
A general rule of thumb used in sizing an
hydraulic reservoir is three to five times the
per-minute flow rate . Reservoir sizing can
also be greatly affected by system char-
acteristics and the type of actuators used .
An hydraulic elevator using a single action
cylinder needs a tank capable of hold-
A general rule of thumb used in sizing a hydraulic reservoir is three to five times
the per-minute flow rate .
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 31
ing nearly all of the system fluid when the
elevator car is at the lowest point of travel
without starving the pump when the car is
at the highest point .
A pressure relief valve is used to limit the
maximum system pressure by allowing the
pressurized fluid to return to the tank dur-
ing periods when the system is not using
the pump’s full volume of flow . When de-
signing the hydraulic system, size the pump
to the nearest maximum flow and pressure
required for proper operation . When the
pump is oversized, the pressure relief valve
will be in constant operation, wasting en-
ergy and creating heat .
The hydraulic filtration system should be in-
cluded as part of the power unit . When the
filter system is located on the pressure side
of the pump, it protects against contamina-
tion for all of the equipment downstream
from the pump . Filtration pore sizes can be
quite small—2 microns or smaller is not un-
common . Disadvantages of a pressure-side
filtration system are pressure drops across
the filtration system as the amount of
contaminants build up; filters and housings
must be capable of withstanding the maxi-
mum pressure produced by the pump; and
any contaminants are passed through the
pump before reaching the filter . Return-line
filtration keeps air and contaminants out of
the tank before reaching the pump . Return-
line filtration is subjected to lower pressures
than pressure-side . With either option, a
differential pressure sensor should monitor
the filter condition and alert personnel to
replace the filter element .
Hydraulic power units often offer additional
features such as a location to mount the
control valve stack and locations to add in-
strumentation . At the very least, a low-level
sight gauge and a system pressure gauge
should be installed . Additional instruction
may include a fluid level sight tube or an
electronic level gauging device . Electronic
pressure transducers allow data collection
and a quicker detection of pressure drops
or spikes . A temperature sensor can monitor
changes in system performance over time .
When specifying the hydraulic power unit, the maximum working flows and pressures
must be defined .
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Discover Morewww2.bwc.com/BWGOverview
Digital-printing technology has made huge gains in recent years, in terms of both
speed and flexibility . As a result, manufacturers of printing finishing systems have
faced challenges to match that growth with new innovation .
VITS International (www .vitsinternational .com), a Blauvelt, New York-based global supplier
of variable repeat sheeting and finishing systems for the printing, packaging, digital and
converting industries, recognized that the digital-printing market needed industrial-strength
finishing systems that could deliver the speed, flexibility and ultra-precise registration con-
trol to sustain commercial printing production rates . To meet that need, VITS developed
the Sprint Variable Data Finishing System, created with a complete, state-of-the-art electric
drive and control platform from Bosch Rexroth .
DIGITAL PRINTING DRIVES INNOVATIONSimilar to web offset printing, digital inkjet printers are capable of high-speed web-fed
output with speeds reaching near-commercial rates of 700 to 1,000 ft/min (FPM) . Howev-
er, digital printing supports variable data printing: it can dynamically vary the content be-
ing produced—not just the number of pages for a given product, but variable imaging and
significant variations in page dimensions . While this provides new abilities for customiza-
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 33
Variable data finishing system keeps pace with digital-printing technologySprint Variable Data Finishing System transforms variable print material to finished product at 1,500 ft/min .
By Deirdre Ryder, VITS International
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 34
tion, it vastly complicates how the printed
web roll is finished . Finishing systems need
to be able to cut, collate and assemble the
pages into a final readable piece in the
most logical order .
The complexity—high speeds plus variable
data printing—was viewed as an important
opportunity for VITS . We decided to take a
leading role in developing robust, industrial-
strength finishing systems that have the
technical capacity, speed and sophistication
to support both offline and inline finishing
with the highest quality .
SPRINT SYSTEM SUPPORTS IN-LINE AND OFF-LINE FINISHINGThe Sprint Variable Data Finishing System
transforms variable print material to fin-
ished product at production rates up to
1,500 FPM . It utilizes patented Clear Chan-
nel registration control technology to en-
able cutting thousands of pages per hour
while keeping ultra-precise page registra-
tion not previously possible with compa-
rable finishing systems .
“Our printing customers wanted to be able
to produce much larger products at much
faster rates of speed,” says Kim Markovich,
VITS International director of product ap-
plications and regional sales and marketing
manager . “Particularly for the direct-mail
marketplace, being able to finish multiple
webs and multiple ribbons and accom-
plish perfect register control meant that
our printing customers could take on more
work and be more productive .”
We developed the Sprint system to sup-
port two variations: in-line systems, which
receive and finish a single web coming
directly from the digital printer, and off-
line multi-web finishing, which enables the
processing of multiple webs into a single
finished signature or book (Figure 1) .
The team at VITS knew that the controls and
drive technology it chose for the Sprint sys-
tem must have the highest levels of versatil-
ity and sophistication—one of the key rea-
sons the team chose Rexroth . “As we looked
at the challenges, we came to the conclusion
that only Bosch Rexroth would be able to
provide the precise control technology we
needed,” says John Salamone, director of
new product development for VITS .
ULTRA-PRECISE MULTI-WEB REGISTRATION CONTROLThe Sprint Finishing System consists of
modular, independently driven compo-
nents controlled by a central Rexroth
IndraMotion MLC motion control platform .
The in-line Sprint system configuration
typically has 10 to 12 driven axes, while the
more advanced multi-web offline version
can have up to 30 driven axes .
Each Sprint module performs specific
functions to convert a printed web into
a completed book or direct mail piece,
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 35
and each utilizes a specific set of Rexroth
IndraDrive servo drives and proven Indra-
Dyn servo motors .
In the off-line multi-web system, multiple
paper rolls are mounted on register splic-
ers that feed the web continuously to the
VITS automatic constant-tension infeed .
The infeed delivers precise gain/tension
control to the web .
The web then passes through an angle bar
system that slits it in half and repositions
one half over the other, before travelling to
a ribbon-gathering station and then over a
folder element to fold the ribbons in half .
Once the fold is complete, the web trav-
els through a shear-slitting module where
the folded web can be trimmed, and
then into the variable data rotary cutter
that cuts each page to size and collates/
stacks the finished product for the next
process, such as final binding or saddle
stitching (Figure 2) .
Maintaining absolute registration control of
multiple webs, so that every page in every
signature is cut to exactly the same dimen-
sion, was one of the most significant techni-
cal hurdles the team faced .
“Nothing is ever printed perfectly—the
length of print can vary by plus or minus
ten-thousandths of an inch from page to
page,” says Salamone . “That doesn’t sound
FINISHINGFigure 1: The VITS variable data multi-web finishing system supports two variations: in-line systems, which receive and finish a single web coming directly from the digital printer, and off-line multi-web finishing, which enables the processing of multiple webs into a single finished signature or book
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 36
like much, but after a hundred pages the
registration can be off significantly .”
VITS enlisted Bruce Parks of Parks Consult-
ing International (www .parksconsulting .net),
a systems integrator with extensive experi-
ence using Rexroth printing system con-
trols, to help develop the Sprint automation
solution . “The Rexroth drives have a large
amount of intelligence built in,” says Parks .
“So we use the drives to maintain registra-
tion on the web in a dynamic fashion, which
then frees up the processing power of the
central IndraMotion MLC controller .”
All drives maintain synchronization with a
virtual master . Tension zones are created
between individual drives in each module
to maintain optimal tension when varia-
tions occur as webs merge, split and are
cut . Groups of drives are also created, al-
lowing adjustments to be made as a group
to bring the web into proper register with
the virtual master .
The team used the industry-specific Indra-
Motion for Printing version of Rexroth’s
IndraMotion MLC system as the automation
platform, featuring IEC 61131-compliant mo-
tion-logic controls and PLCopen function
blocks along with extensive software librar-
ies for printing and converting functions .
“IndraMotion for Printing provides engi-
STITCHINGFigure 2: Once the fold is complete, the web travels through a shear-slitting module where the folded web can be trimmed, and then into the variable data rotary cutter that cuts each page to size and col-lates/stacks the finished product for the next process, such as final binding or saddle stitching.
www.controldesign.com
eHANDBOOK: Motors, Motion & Drives 37
neering tools that work right out of the
box to accomplish most of the web han-
dling tasks,” says Parks . “We then used
Rexroth’s PLCopen function blocks as the
starting point to build the special cam-
ming profiles and functions we needed for
the proprietary VITS Clear Channel regis-
tration capability .”
ROTARY CUTTING CHIP CONTROLThe other major challenge for the Sprint
team was having a rotary cutter that could
handle variable data—infinitely variable
image sizes ranging from 5 to 25 inches—
and be configured to cut different-width
chips—the blank space between pages on
the web roll—all with the push of a button,
rather than a time-consuming changeover .
In the rotary-cutter module, two knives cut
the chip out; the knives are separated by
the width of the chip, and the cutting needs
to be synchronized with the speed of the
web through the system . “Our camming
process allows us to cut variable-size prod-
ucts with multiple knives and still maintain
chip size because we always synchronize
with the web speed through the cutting
zone,” Salamone says .
The Clear Channel register control provides
faster size changes, as well as cut toler-
ances never before provided by standard
finishing systems, which is a competitive
advantage for both VITS International and
its customers that choose the system .
COLLABORATION CHEMISTRYThis is the first system we’ve produced
using a complete Bosch Rexroth drive and
control platform—a decision that was made
after a thorough evaluation .
We had a great relationship with our pre-
vious supplier who was a close business
partner and was always there to work
through any issues . With Bosch Rexroth,
we found similar values and commitment .
More importantly, it was the technology
that allowed us to develop our equipment
much faster, with world-class accuracy that
none of our competitors have . We now
have Rexroth-equipped machines located
all around the world . Their performance and
reliability is good; they are working flaw-
lessly .
It has turned out to be the best decision
for our growth and our future to work with
Rexroth . We could not imagine doing what
we are doing now without their technology
and their capabilities . With a lot of input
from our team and the right technology,
we were able to solve the challenges we
encountered . It took all three partners—
Bosch Rexroth, VITS International and Parks
Consulting International—to go from ideas
to working solutions .
Deirdre Ryder is president and CEO of VITS
International in Blauvelt, New York . Contact
her at deirdrer@vitsinternational .com .
The S6 platform is built for flexibility and demanding applications. Some features include:
• 0.75...5.5kW power range• Worldwide voltage input: 185 - 550VAC• On-board EtherCAT slave (Profinet and Powerlink optional)• On-board SIL3 Safe-Torque-Off• Integrated brake supply: 2Amps @24 VDC• Dual channel, Universal encoder connection• Operates induction, servo, torque, & linear motors
KEB’s S6 Servo Drive comes with everything on board
5100 Valley Industrial Blvd. S Shakopee, MN | 952.224.1400 | [email protected] | kebblog.com/s6-servo-drive
SIL3 SafeTorqueOff
VERSATILE CONTROL IN A COMPACT FORM
50mm