SACA C-207 Programmable Controller Systems 1 Exam Prep
2026: Complete Study Guide with Practice Questions, PLC
Programming, and Certification Review
1. What are the software programs that connect the hardware of a PLC to a
network and allow them to communicate with other devices?
• Correct Answer: Drivers
• Rationale: Drivers act as translators between the PLC's hardware (like the processor
and I/O modules) and the network protocol, enabling them to send and receive data.
2. What three key components are contained within a PLC project file?
• Correct Answer: Ladder logic programs, hardware configuration, tags and
communication configuration
• Rationale: A PLC project file is a complete package. It contains the user-created logic
(ladder logic), the definition of the physical hardware setup (hardware configuration),
and the variables (tags) and network settings needed for the program to run and
communicate.
3. What does a PLC use to store the status of input and output modules by
assigning each terminal a specific place in memory?
• Correct Answer: Tag
• Rationale: A tag is a named area in the PLC's memory. It's assigned to a specific
terminal or piece of data, allowing the programmer to reference the status of that
input or output throughout the program.
4. Which part of a PLC is responsible for executing the logic program?
• Correct Answer: Processor
• Rationale: The processor (or CPU) is the "brain" of the PLC. It reads the input data,
executes the stored program based on that data, and then updates the outputs
accordingly.
, 5. Should the power supply located in the chassis or backplane be used to
power external field devices?
• Correct Answer: False
• Rationale: The chassis/backplane power supply is specifically designed to power the
PLC's own internal modules (processor, I/O cards, etc.). Powering external devices like
sensors or actuators requires a separate, external power supply.
6. What is the sixth basic component of a PLC, alongside the power supply,
input modules, output modules, chassis, and processor?
• Correct Answer: Programming Device
• Rationale: A PLC needs a way to receive its program. A programming device (like a
laptop with software, or a dedicated handheld programmer) is used to create,
transfer, and monitor the control logic.
7. Along with Ethernet, what is the second most popular communication
protocol used with PLCs?
• Correct Answer: Universal serial bus (USB)
• Rationale: While Ethernet is dominant for industrial networks, USB is extremely
common for direct, short-range connections between a programming device (like a
laptop) and a PLC for programming and troubleshooting.
8. Typically, will a USB driver automatically start when a programming device
detects the connection?
• Correct Answer: False
• Rationale: While the operating system might detect new hardware, the specific
driver for the PLC communication often requires manual installation or configuration
using the PLC manufacturer's software.
9. What is the proper sequence of operation within a PLC's scan cycle?
• Correct Answer: Examine inputs, perform logic, update outputs
• Rationale: This is the fundamental "scan cycle" of a PLC. It first reads the state of all
physical inputs, then executes the ladder logic program based on those input states,
and finally writes the resulting states to all physical outputs.
10. Which statement accurately describes PLC Program Mode?
• Correct Answer: Allows the user to download, upload, edit and save project files.
The processor does not scan or execute the ladder program, and outputs are not
energized.
,• Rationale: Program (or "Offline") mode is for maintenance and development. The
program is not running, which ensures safety while making changes to the project
files.
11. A CTU instruction's DN (Done) bit is ___ whenever the accumulated (ACC)
value is greater than or equal to the Preset (PRE) value and ___ when the value
is less than the preset (PRE) value.
• Correct Answer: true, false
• Rationale: The "Done" bit on a counter is a status bit that becomes true (1) when the
counter has reached or exceeded its target value. It automatically resets to false (0)
when the accumulated value falls below the preset.
12. In a time-driven sequence triggered by pressing PB1, which statement
accurately describes the sequence shown in the program?
• Correct Answer: PB1 pressed, Lube Pump Motor On, Impeller Motor on, 10 seconds
goes by, Impeller Motor off, 5 more seconds Lube Pump Motor off.
• Rationale: The logic uses timers to sequence events. Pressing PB1 starts the first
timer and turns on the Lube Pump. The Impeller starts after the first timer's done bit
is true. After another timer delays, the Impeller turns off, and a final timer delays
before turning off the Lube Pump.
13. If a PLC is connected to a computer using a SINGLE CABLE, regardless of
whether the network protocol is Ethernet or USB, what type of network is this?
• Correct Answer: point-to-point
• Rationale: A point-to-point network is the simplest form of connection, involving a
direct link between exactly two devices. The physical cable is the "point" that
connects them.
14. If a process requires a technician to edit and test a PLC and HMI
communicating with each other via an Ethernet network, how many different IP
addresses would need to be configured?
• Correct Answer: 4
• Rationale: On an Ethernet network, every intelligent device needs a unique IP
address. This scenario would involve the technician's PC, the PLC, and the HMI panel,
totaling three devices. However, if the PC, PLC, and HMI are all communicating on
the same managed switch, that switch may also have an IP address for configuration,
making a potential fourth. Alternatively, the question may be implying that the PLC
and HMI each have an IP, and the PC has an IP, for a total of three. Given the answer
provided as "4", it's possible the context includes a managed switch or two separate
network interfaces on the PC. (Note: The provided answer key states "4").
, 15. Which statement describes PLC Run mode?
• Correct Answer: Allows the user to upload, save, edit, and monitor the operation of
the PLC project. The processor executes the ladder program, monitors status of
inputs, and energizes appropriate outputs.
• Rationale: Run mode is the operational state of the PLC. The processor is actively
scanning inputs, executing the logic, and updating outputs to control the process.
While in this mode, a technician can typically monitor live data.
16. In the module tag Local:1:I.Data, what does the "I" refer to?
• Correct Answer: Input
• Rationale: In standardized PLC addressing (like Rockwell Automation's), the colon is
used as a delimiter. "Local:1" specifies the location and slot number, and "I" stands
for the module's data type, which in this case is Input. This is where the status of
input points is stored.
17. When voltage is applied to the terminal of an active high PLC input module,
what is the state of an XIO instruction with the same address?
• Correct Answer: False
• Rationale: An XIO (eXamine If Open) instruction looks for an "off" or false condition.
When voltage is applied to the input, the corresponding tag in memory is True. Since
the XIO is looking for False, it evaluates to False, and logic will not flow through it.
18. When voltage is applied to the terminal of a PLC input module, what is the
state of an XIC instruction with the same address?
• Correct Answer: True
• Rationale: An XIC (eXamine If Closed) instruction looks for an "on" or true condition.
When voltage is applied, the tag's value is True. The XIC evaluates to True, and logic
can flow past it.
19. After creating a new project, naming it, and configuring the controller and
I/O, what is the next logical step to enter the control logic?
• Correct Answer: Open the program editor and add rungs
• Rationale: The hardware configuration defines the physical setup. The next step is to
create the software logic that tells the hardware what to do. This is done by opening
the programming editor (e.g., the ladder logic editor) and building the program,
typically one rung at a time.
20. PLC input/output diagrams are used to show the specific physical
connections between the _______ and the PLC I/O terminals.
2026: Complete Study Guide with Practice Questions, PLC
Programming, and Certification Review
1. What are the software programs that connect the hardware of a PLC to a
network and allow them to communicate with other devices?
• Correct Answer: Drivers
• Rationale: Drivers act as translators between the PLC's hardware (like the processor
and I/O modules) and the network protocol, enabling them to send and receive data.
2. What three key components are contained within a PLC project file?
• Correct Answer: Ladder logic programs, hardware configuration, tags and
communication configuration
• Rationale: A PLC project file is a complete package. It contains the user-created logic
(ladder logic), the definition of the physical hardware setup (hardware configuration),
and the variables (tags) and network settings needed for the program to run and
communicate.
3. What does a PLC use to store the status of input and output modules by
assigning each terminal a specific place in memory?
• Correct Answer: Tag
• Rationale: A tag is a named area in the PLC's memory. It's assigned to a specific
terminal or piece of data, allowing the programmer to reference the status of that
input or output throughout the program.
4. Which part of a PLC is responsible for executing the logic program?
• Correct Answer: Processor
• Rationale: The processor (or CPU) is the "brain" of the PLC. It reads the input data,
executes the stored program based on that data, and then updates the outputs
accordingly.
, 5. Should the power supply located in the chassis or backplane be used to
power external field devices?
• Correct Answer: False
• Rationale: The chassis/backplane power supply is specifically designed to power the
PLC's own internal modules (processor, I/O cards, etc.). Powering external devices like
sensors or actuators requires a separate, external power supply.
6. What is the sixth basic component of a PLC, alongside the power supply,
input modules, output modules, chassis, and processor?
• Correct Answer: Programming Device
• Rationale: A PLC needs a way to receive its program. A programming device (like a
laptop with software, or a dedicated handheld programmer) is used to create,
transfer, and monitor the control logic.
7. Along with Ethernet, what is the second most popular communication
protocol used with PLCs?
• Correct Answer: Universal serial bus (USB)
• Rationale: While Ethernet is dominant for industrial networks, USB is extremely
common for direct, short-range connections between a programming device (like a
laptop) and a PLC for programming and troubleshooting.
8. Typically, will a USB driver automatically start when a programming device
detects the connection?
• Correct Answer: False
• Rationale: While the operating system might detect new hardware, the specific
driver for the PLC communication often requires manual installation or configuration
using the PLC manufacturer's software.
9. What is the proper sequence of operation within a PLC's scan cycle?
• Correct Answer: Examine inputs, perform logic, update outputs
• Rationale: This is the fundamental "scan cycle" of a PLC. It first reads the state of all
physical inputs, then executes the ladder logic program based on those input states,
and finally writes the resulting states to all physical outputs.
10. Which statement accurately describes PLC Program Mode?
• Correct Answer: Allows the user to download, upload, edit and save project files.
The processor does not scan or execute the ladder program, and outputs are not
energized.
,• Rationale: Program (or "Offline") mode is for maintenance and development. The
program is not running, which ensures safety while making changes to the project
files.
11. A CTU instruction's DN (Done) bit is ___ whenever the accumulated (ACC)
value is greater than or equal to the Preset (PRE) value and ___ when the value
is less than the preset (PRE) value.
• Correct Answer: true, false
• Rationale: The "Done" bit on a counter is a status bit that becomes true (1) when the
counter has reached or exceeded its target value. It automatically resets to false (0)
when the accumulated value falls below the preset.
12. In a time-driven sequence triggered by pressing PB1, which statement
accurately describes the sequence shown in the program?
• Correct Answer: PB1 pressed, Lube Pump Motor On, Impeller Motor on, 10 seconds
goes by, Impeller Motor off, 5 more seconds Lube Pump Motor off.
• Rationale: The logic uses timers to sequence events. Pressing PB1 starts the first
timer and turns on the Lube Pump. The Impeller starts after the first timer's done bit
is true. After another timer delays, the Impeller turns off, and a final timer delays
before turning off the Lube Pump.
13. If a PLC is connected to a computer using a SINGLE CABLE, regardless of
whether the network protocol is Ethernet or USB, what type of network is this?
• Correct Answer: point-to-point
• Rationale: A point-to-point network is the simplest form of connection, involving a
direct link between exactly two devices. The physical cable is the "point" that
connects them.
14. If a process requires a technician to edit and test a PLC and HMI
communicating with each other via an Ethernet network, how many different IP
addresses would need to be configured?
• Correct Answer: 4
• Rationale: On an Ethernet network, every intelligent device needs a unique IP
address. This scenario would involve the technician's PC, the PLC, and the HMI panel,
totaling three devices. However, if the PC, PLC, and HMI are all communicating on
the same managed switch, that switch may also have an IP address for configuration,
making a potential fourth. Alternatively, the question may be implying that the PLC
and HMI each have an IP, and the PC has an IP, for a total of three. Given the answer
provided as "4", it's possible the context includes a managed switch or two separate
network interfaces on the PC. (Note: The provided answer key states "4").
, 15. Which statement describes PLC Run mode?
• Correct Answer: Allows the user to upload, save, edit, and monitor the operation of
the PLC project. The processor executes the ladder program, monitors status of
inputs, and energizes appropriate outputs.
• Rationale: Run mode is the operational state of the PLC. The processor is actively
scanning inputs, executing the logic, and updating outputs to control the process.
While in this mode, a technician can typically monitor live data.
16. In the module tag Local:1:I.Data, what does the "I" refer to?
• Correct Answer: Input
• Rationale: In standardized PLC addressing (like Rockwell Automation's), the colon is
used as a delimiter. "Local:1" specifies the location and slot number, and "I" stands
for the module's data type, which in this case is Input. This is where the status of
input points is stored.
17. When voltage is applied to the terminal of an active high PLC input module,
what is the state of an XIO instruction with the same address?
• Correct Answer: False
• Rationale: An XIO (eXamine If Open) instruction looks for an "off" or false condition.
When voltage is applied to the input, the corresponding tag in memory is True. Since
the XIO is looking for False, it evaluates to False, and logic will not flow through it.
18. When voltage is applied to the terminal of a PLC input module, what is the
state of an XIC instruction with the same address?
• Correct Answer: True
• Rationale: An XIC (eXamine If Closed) instruction looks for an "on" or true condition.
When voltage is applied, the tag's value is True. The XIC evaluates to True, and logic
can flow past it.
19. After creating a new project, naming it, and configuring the controller and
I/O, what is the next logical step to enter the control logic?
• Correct Answer: Open the program editor and add rungs
• Rationale: The hardware configuration defines the physical setup. The next step is to
create the software logic that tells the hardware what to do. This is done by opening
the programming editor (e.g., the ladder logic editor) and building the program,
typically one rung at a time.
20. PLC input/output diagrams are used to show the specific physical
connections between the _______ and the PLC I/O terminals.
