The (8, 16, 24, ….. 64). PLC input cards

The
CPU unit of the PLC is a storage of the ladder logic program, as well as the
information processor collected and delivered to external devices controlled by
the PLC. The CPU contains all the relevant information required to fully
automate the process in which it is involved. Only one CPU unit is allowed in
the rack configuration of the old systems currently available by all PLC
manufacturers .The latest systems allow the designer to integrate multiple CPU
units into the hardware design of their process. This means allowing software
designers (peace logic) to divide the process across multiple computing
devices, making the integrity of the code more important from a security
perspective.

2.1.2.3
Input and Output Cards

We Will Write a Custom Essay Specifically
For You For Only $13.90/page!


order now

The
external information that is transferred to and from the PLC occurs on several
input and output (I / O) cards. These I / O cards can contain multiple contact
points, depending on user needs, and can be analog or similar with regard to
the type of information sent and received. We will now give a brief overview of
the input and output cards and devices they control.

Input Cards: As
noted, access cards can be equipped with multiple access points, which are only
in the developer’s discretion. One PLC card input generally comes with its
connections points at multiples of 8, with a greater than 64 (8, 16, 24, …..
64). PLC input cards collect their information from associated control units
such as temperature sensors, level sensors, proximity keys, and VDF.

Output Cards: As with
the input cards of PLC, the outputs cards can be equipped with multiple contact
points. The number available in any product generally reflects those available
for input cards. PLC output cards send control information in the form of
analog and digital signals. These signals are used by different controllers as
an activation mechanism or as a control point.

2.1.3
SCADA and Automation System Overview

PLC
is the backbone of the engineering system for an industrial network. The
information that is sent by PLC is collected for the SCADA system via input and
output cards (rack mount configuration) or provide input and output point
(block configuration). A SCADA computer is an information station through which
the operator’s control room, and anyone else with intentional or unintentional
access can view the real-time functions of the automated system. This station
is generally connected over the Ethernet network to the existing network of
facilities. The SCADA system receives its information directly from the CPU via
the Ethernet connection provider. This can be in the form of a physical
connection card, if you are configuring a rack or internal protocol
configuration, block style is used. Also, it is now possible to share this
information via wireless communication cards too, which just adds another layer
to the security issue

 

The
SCADA standard system in Figure 2.6 acts as a control device that is connected
to one or many PLC units throughout a given infrastructure system. The SCADA
itself is nothing more than a standard industrial grade computer, running a
vendor-specific piece of software, which is used to watch and track the states
and circumstances of each device connected to its associated control units.
These devices are generally calibrated with the PC system of PLC and SCADA when
the initial installation is assumed to be accurate thereafter. This assumption
is critical to understanding the severity of the prejudice. Since the control
room operator studies the reliability of the data received by the PLC system
and calibrates the devices using the same PLC as the calibration method, any
individual that access to the PLC can directly affect the system and falsify
the data to the SCADA system.