Prisma Plus - error

ASI-Safe
enhances infrastructure
Fonterra’s Clandeboye factory
in Southland has embarked
on the roll-out of a new safety
infrastructure following the recent
trial of Schneider-Electric’s Asi-
Safety at Work software on the giant
facility’s cheese production line.
“A significant advantage of the new
ASi-Safe system,” says Clandeboye
automation engineer Tim Holt, “is the
way it interfaces seamlessly with our In
Touch SCADA technology. In addition to
a much better safety environment, the
technology provides easier monitoring
and control of the cheese mellowing
process. We will now extend it to other
parts of the facility.”
Personnel on the ‘mellowing’ line are
required to stop production periodically
to take samples for batch testing and
quality control. It is not safe to attempt
this with the conveyor lines continuing to
operate, and until the installation of the
ASi-Safe technology, the line was shut
down manually. And that required a
certain amount of coordination: all lines
further up-stream in the production
process also had to be stopped to
prevent bottlenecks.
To streamline the stopping and starting
of the process and improve safety
parameters, Clandeboye
commissioned Dave McIvor (owner of
Industrial Controls South Canterbury
Ltd in Christchurch) to design and
install an automated system. “We
discussed three options,” says Holt,
“and the ASi-Safe solution was by far
the most cost-effective.”
ASi-Safe runs on an ASi-bus network –
technology now incorporated into the
Clandeboye system with the fitting of
an ASi-bus card to the line’s existing
Modicon PLC. The ASi-Safe system
comprises the software and a number
of sensors and ASi-safe modules.
“The conveyors in the mellowing line
have hinged covers,” says McIvor,
“and the sensors were fitted to them.
As soon as the operators (there are four
‘sampling’ stations) lift a cover, a signal is
sent to the PLC to halt the line.”
At the same time, the PLC
communicates with up-stream
processing lines, synchronising their
stopping-and-starting with that of the
sample-testing line. “It was an easy
system to install,” says McIvor. “Most of
work involved configuring the ASi-Safe
software with my lap-top.”
Clandeboye says the system’s ability to
interface with the facility’s In Touch
SCADA system also provides useful
trending information about unrelated
stoppages (those un-connected to
sampling procedures), and so helps with
operational management issues.
“None of the other systems we
investigated were able to reflect
individual devices on the computer
screens in our control room,” says Holt.
“Without ASi-Safe, getting the status of
all devices on the In Touch system would
have been a real ‘mission’ – involving lots
of additional wiring and separate PLCs.”
ASi-Safe is TÜV-certified and may be
used up to category 4 (conforming to
EN954-1) and is for use with safety
sensors and other safety control
products to guarantee fast operation.
Benefits
ASi-Safe technology offers plant
operators a variety of benefits, including:
• schematic design time is greatly
reduced
• installation time is greatly reduced
• the risk of wiring errors is greatly
reduced
• safety I/O signals are integrated into
and managed by the same, process
I/O system
• the ability to use a standard ASi-bus
card in a standard PLC offers cost
reductions
• input signals are processed rapidly
(response time < 35ns) compared
with a purpose-designed safety PLC.
For more information, contact:
Chris Cooper
Product Manager
Machine Control
Schneider Electric NZ
Phone: 09 829 0490
email: chris.cooper@nz.schneiderelectric.com