TPC PLC TEST EXAM QUESTIONS AND ANSWERS
What is the purpose of a rung comment? - Answers -Explain a program operation
According to the stack rule, what happens each time a load instruction is used? -
Answers -The logic is pushed down one level
When programming in ladder logic, tags are used to - Answers -identify a device
In Boolean programming, all logic is some combination of which operations? - Answers
-AND,NOT,OR
Although and output generally appears on only one rung of a ladder logic program, it
may be energized by several sets of conditions that appear as - Answers -branches
The temperature range a thermocouple can detect is determined by the - Answers -
combination of metals used
The number of TTL, output devices a TTL output module can drive is called - Answers -
fanout
If an I/O module supplies current, it is considered a(n) ______ module. - Answers -
sourcing
To be useful to a PLC, analog input signals must be _______ by an input module -
Answers -digitized
Which output device is sometimes used as a repeater, using a signal to control several
different loads? - Answers -Relay
The easiest way to develop a PLC program is usually to divide the logic into different -
Answers -tasks
Which type of data transmission uses a single frequency? - Answers -baseband
Which network control structure makes it possible for processors to communicate? -
Answers -Protocol
Which mathematical operation is the same as the Boolean OR function? - Answers -
Addition
The Boolean NOT function acts as a(n) - Answers -inverter
In ladder logic, the output instruction that looks like a coil is called - Answers -output
energize
, Which device creates a numerically coded binary signal to represent an output
condition? - Answers -Encoder
Which digit is the most significant in the number 2684? - Answers -2
Most hardware problems in a PLC system occur in the - Answers -I/O devices
Once you understand how a PLC system works, the next step in troubleshooting it is to
- Answers -gather information
Which documentation shows how all field devices are wired and connected to the
controller? - Answers -Schematic diagram
Which of the following is the most common cause of a program problem? - Answers -
Changes made to the original program
As a good general rule, you should replace the battery in a programmable controller -
Answers -annually
A programmable logic controller is a device that - Answers -responds to status changes
in a system
The two circuits in an electromagnetic relay are the control circuit and the _______
circuit. - Answers -power
The three main components of a PLC are the programming device, processor unit, and
- Answers -I/O section
The memory used for PLC firmware is usually - Answers -nonvolatile
The logical decisions of a programmable controller are made in the - Answers -
processor
Seven binary digits in the ASCII code can represent a certain number of alphanumeric
characters. How many characters can be represented by a code that uses one more
digit? - Answers -Twice as many
An output interface contains a _______ that produces a ________ signal in response to
the output of the logic system. - Answers -Transistor; high-voltage
Parallel data transfer is ______ than serial transfer, but serial transfer is______ -
Answers -Faster, simpler
One of the problem with microprocessors is that they must perform logic operations
______ and perform them _______. - Answers -One-by-one; in sequence
What is the purpose of a rung comment? - Answers -Explain a program operation
According to the stack rule, what happens each time a load instruction is used? -
Answers -The logic is pushed down one level
When programming in ladder logic, tags are used to - Answers -identify a device
In Boolean programming, all logic is some combination of which operations? - Answers
-AND,NOT,OR
Although and output generally appears on only one rung of a ladder logic program, it
may be energized by several sets of conditions that appear as - Answers -branches
The temperature range a thermocouple can detect is determined by the - Answers -
combination of metals used
The number of TTL, output devices a TTL output module can drive is called - Answers -
fanout
If an I/O module supplies current, it is considered a(n) ______ module. - Answers -
sourcing
To be useful to a PLC, analog input signals must be _______ by an input module -
Answers -digitized
Which output device is sometimes used as a repeater, using a signal to control several
different loads? - Answers -Relay
The easiest way to develop a PLC program is usually to divide the logic into different -
Answers -tasks
Which type of data transmission uses a single frequency? - Answers -baseband
Which network control structure makes it possible for processors to communicate? -
Answers -Protocol
Which mathematical operation is the same as the Boolean OR function? - Answers -
Addition
The Boolean NOT function acts as a(n) - Answers -inverter
In ladder logic, the output instruction that looks like a coil is called - Answers -output
energize
, Which device creates a numerically coded binary signal to represent an output
condition? - Answers -Encoder
Which digit is the most significant in the number 2684? - Answers -2
Most hardware problems in a PLC system occur in the - Answers -I/O devices
Once you understand how a PLC system works, the next step in troubleshooting it is to
- Answers -gather information
Which documentation shows how all field devices are wired and connected to the
controller? - Answers -Schematic diagram
Which of the following is the most common cause of a program problem? - Answers -
Changes made to the original program
As a good general rule, you should replace the battery in a programmable controller -
Answers -annually
A programmable logic controller is a device that - Answers -responds to status changes
in a system
The two circuits in an electromagnetic relay are the control circuit and the _______
circuit. - Answers -power
The three main components of a PLC are the programming device, processor unit, and
- Answers -I/O section
The memory used for PLC firmware is usually - Answers -nonvolatile
The logical decisions of a programmable controller are made in the - Answers -
processor
Seven binary digits in the ASCII code can represent a certain number of alphanumeric
characters. How many characters can be represented by a code that uses one more
digit? - Answers -Twice as many
An output interface contains a _______ that produces a ________ signal in response to
the output of the logic system. - Answers -Transistor; high-voltage
Parallel data transfer is ______ than serial transfer, but serial transfer is______ -
Answers -Faster, simpler
One of the problem with microprocessors is that they must perform logic operations
______ and perform them _______. - Answers -One-by-one; in sequence
