SERCOS News - Issue 1 - 2008

10 Application
The Real-Time Ethernet Magazine
ROVEMA introduces packaging machine
with SERCOS III communications
At ROVEMA, intelligent packaging means the
responsible, innovative design of individual
components and entire process sequences. The
company supplies complete solutions for sophisticated,
complex packaging applications. Forming,
filling, sealing, case packing and retail packaging
for today‘s market require a holistic approach
which goes beyond the individual component
level to include the specific customer process.
A very powerful and highly flexible
control system is needed to support the
broad product portfolio and the highly
complex packaging operations. Rovema
has been using its own proprietary PCbased
P@ck-Control system for many
years on its packaging machines. Motion
control, PLC and visualization are the
main features of ROVEMA control solutions.
The motion control subsystem is
based on centralized control architecture.
P@ck-Control takes total control of axis
coordination and position control. The
interface to the speed-controlled drives
has traditionally been a conven tional
+/-10Volt interface with incremental
encoder feedback. Interbus-S has provided
the link between the integral software
PLC in the P@ck-Control system
and the outside world.
The engineers at Rovema have designed
the Ethernet-based SERCOS III real
time communications system into the
new P@ck-Control generation. A new
VPL260 tubular bag machine with this
communications interface will be on
display for the first time at Interpack
2008. The machine also features continuous
volumetric filling. Communications
with the speed-controlled
drives and digital I/Os flow through
the SERCOS III interface. Two highspeed,
high-precision linear motors,
which drive the longitudinal sealing
tools, put the real time performance
of the bus system to the test.
There has been general agreement for
some time among the control system
engineers at ROVEMA that the +/-10
Volt interface will have to be replaced
by a future-proof Ethernet-based bus
system. Given the large selection of
systems on the market, it was no easy
task for ROVEMA to make the right
choice. One major criterion was of
course the bus system's ability to support
complex ROVEMA control technology.
The availability of drives and I/Os
and acceptance by ROVEMA customers
worldwide were also important
consi derations. However, support for
ROVEMA - individual packaging solutions
power ful and strictly standardized
communications, I/O and drive profiles
was the decisive factor. The +/-10
Volt interface was able to accommodate
special customer configurations,
and the new solution will have to offer
the same flexibility in the future. To
achieve this goal, the drives and I/Os
have to speak the same language.
Another goal of migration to a stateof-the-art
bus system is to exploit highperformance,
low-cost hardware components
which reduce connectivity
costs. Following an in-depth analysis of
the competing bus systems, the decision
in favor of SERCOS III was made
at the beginning of 2007. With the aid