PREVENTIVE MAINTENANCE
lSinekn tsoi nggre tahtee r power
Many systems are emerging to connect sensors to
industrial power and communications networks, with
IO-Link and Power over Ethernet guring prominently.
They are compared and contrasted in the overall
context of the industrial data communications market
ABy Brian Wall t its simplest, preventive
maintenance uses timebased
maintenance, which
services critical pieces
of equipment at set
intervals, regardless of usage levels or
circumstances, based on a ‘Mean Time
To Failure’ (MTTF) calculation. The next
level of maintenance considers usage
and triggers a service after a piece of
equipment has completed a certain
number of production cycles.
“While neither of these approaches
uses the data-intensive Arti cial
Intelligence AI required for predictive
maintenance, the second level does
require a feed of data from industrial
sensors and/or PLCs on machines or
lines,” says Andy Graham, solutions
manager, SolutionsPT (pictured, right). “A
strong preventive maintenance strategy
also requires historic records of past
inspections and machine performance
to best plan what can be a complex
schedule.”
For manufacturing plants to
e ectively communicate and manage
this data, there are multiple options
available when it comes to preventive
maintenance. He advises: “IO-Link is
a cost-e ective, open, point-to-point
communications protocol. It is
bi-directional, so will transmit data/
instructions in both directions over
a short distance between two separate
endpoints or nodes.” Commonplace
within industrial settings, IO-Link is often
used to communicate with sensors and
actuators in factories. These connect
via Fieldbus, which enables them to be
placed across the facility. All of these edge
devices connect to a master device that
communicates to an operator.
POINT-TO-POINT TOPOLOGY
When looking at this protocol with
preventive maintenance in mind, there
are several aspects to consider, states
Graham. “First, IO-Link is versatile,
meaning it is capable of integration
into existing systems. It is also fairly
simple to install, compared to other
approaches, including Power over
Ethernet. The point-to-point topology
means that, with enough data points on
the equipment, issues can be detected
and communicated in almost real time.
The versatility of IO-Link also translates
to scalability.”
By contrast, Power over Ethernet
(PoE) means low-energy industrial
sensors can be installed and take power
from network cabling, without having
to connect to traditional power outlets.
“This means power can be delivered to
areas without needing to install additional
electrical infrastructure, resulting in
reduced installation costs, more exible
and responsive deployments for datagathering
capabilities, and pursuant
productivity enhancements. Operators
can plug PoE-enabled edge devices into
existing networks very easily, allowing
straightforward integration with legacy
hardware,” he points out.
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