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PLC1 PMMI Study Set Exam Questions and
Answers 100% Pass
Describe the function of a programmable logic controller and give an application - ANS PLCs
are industrial computers that control machines and other industrial applications. PLCs have
replaced hardwired devices, such as relay coils and contacts
PLC applications - ANS Assembly machines
Automatic Transfer Lines
Packaging LInes
Robots
List the advantages of a PLC - ANS Less space
Lower Cost
Resistance to Environment
Direct Interface
Easy Programming
Flexible
Advantages - Direct Interface - ANS Standard computers require a complex and limited
system to interface to real-world components. A PLC's interface is directly wired to these
components
6 Components of a PLC - ANS Input Modules
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, ©FYNDLAY 2025 ALL RIGHTS RESERVED
Output Modules
Processor Module (or Controller)
PLC Power Supply
Programming Device
I/O Chassis
Describe the Basic Operation of a PLC - ANS To scan instructions, monitor the status of input
devices, and produce outputs based on the status of the inputs.
Describe how I/O modules communicate with the PLC processor - ANS Each input, or field
device, opens and closes circuits to an individual terminal on an input module. When an input
or output module is configured, each terminal is assigned a tag that identifies the location of
the terminal status. The input module transmits (multicasts) the data to the system on a regular
basis so that the processor can collect the information via scan and enact logic/programming
based on input/output data/signal
Basic PLC Processor Operation - ANS Controller contains a ladder logic program that
references the tags of the input devices and similar tags of output devices. The controller then
uses that input information to determine the status of each individual rung of its program. The
status of the rungs are then transferred to an output tag where the output module turns the
real world devices on and off appropriately
Basic Operation of Serial Communication - ANS USB connects a host, which initiates a data
transaction with a device. USB groups the binary data from the host into fields, which are then
organized into packets. Packets are bundled into frames, which are transmitted to the device
over a half-duplex differential pair of wires (D+ and D-). Ones and zeros are determined by
voltage difference between D+ and D-. A 1 is defined as D+ 200 mV greater than D- and 0 is
defined as D+ 200 mV less than D-
Recognize Languages used to program a PLC - ANS Ladder Logic
Sequential Function Chart
Structured Text
Function Block Diagram
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PLC1 PMMI Study Set Exam Questions and
Answers 100% Pass
Describe the function of a programmable logic controller and give an application - ANS PLCs
are industrial computers that control machines and other industrial applications. PLCs have
replaced hardwired devices, such as relay coils and contacts
PLC applications - ANS Assembly machines
Automatic Transfer Lines
Packaging LInes
Robots
List the advantages of a PLC - ANS Less space
Lower Cost
Resistance to Environment
Direct Interface
Easy Programming
Flexible
Advantages - Direct Interface - ANS Standard computers require a complex and limited
system to interface to real-world components. A PLC's interface is directly wired to these
components
6 Components of a PLC - ANS Input Modules
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, ©FYNDLAY 2025 ALL RIGHTS RESERVED
Output Modules
Processor Module (or Controller)
PLC Power Supply
Programming Device
I/O Chassis
Describe the Basic Operation of a PLC - ANS To scan instructions, monitor the status of input
devices, and produce outputs based on the status of the inputs.
Describe how I/O modules communicate with the PLC processor - ANS Each input, or field
device, opens and closes circuits to an individual terminal on an input module. When an input
or output module is configured, each terminal is assigned a tag that identifies the location of
the terminal status. The input module transmits (multicasts) the data to the system on a regular
basis so that the processor can collect the information via scan and enact logic/programming
based on input/output data/signal
Basic PLC Processor Operation - ANS Controller contains a ladder logic program that
references the tags of the input devices and similar tags of output devices. The controller then
uses that input information to determine the status of each individual rung of its program. The
status of the rungs are then transferred to an output tag where the output module turns the
real world devices on and off appropriately
Basic Operation of Serial Communication - ANS USB connects a host, which initiates a data
transaction with a device. USB groups the binary data from the host into fields, which are then
organized into packets. Packets are bundled into frames, which are transmitted to the device
over a half-duplex differential pair of wires (D+ and D-). Ones and zeros are determined by
voltage difference between D+ and D-. A 1 is defined as D+ 200 mV greater than D- and 0 is
defined as D+ 200 mV less than D-
Recognize Languages used to program a PLC - ANS Ladder Logic
Sequential Function Chart
Structured Text
Function Block Diagram
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