Flexible Automation Chapter 1&2
List at least five data that is held in PLC system memory.
Flag status file, input file, output file, bit file, timer file, counter file, integer data file, control file
A(n) ______________________________ converts the digital output signals back to analog signals.
DAC
Transmitted data that have an even number of ones uses ______________________________ parity.
Even
EEPROM is an acronym for ______________________________.
Electrically erasable programmable read only program
PLC control applications could be: A) Controlling multiple motor starters. B) On and off control of a pump. C) Sorting boxes on a conveyor system by zip code. D) All of the above.
D) All of the above.
You can place two or more input instructions in series or parallel with each other in a PLC ladder logic rung. TRUE OR FALSE
True
Which of the following component(s) can be found in a PLC? A. central processing units B. input/output ports C. power supply D. All of the above.
D. All of the above.
Which of the following is part of the central processing unit (CPU)? A. RAM and ROM memory units B. Microprocessor C. Support chips D. All of the above.
D. All of the above.
An advantage of changing a relay logic circuit over a PLC logic control is ____. A. it is less expensive B. it is less time consuming to program C. it has less current capability D. None of the above.
D. None of the above.
Which of the following statements is false? A. Discrete input port can be either sourcing or sinking. B. Discrete output port can be either sourcing or sinking. C. ADC module converts analog signal to digital signal. D. None of the above.
D. None of the above.
Which of the following statements is false? A. Industrial PCs can replace PLCs. B. Industrial PCs are more expensive than PLCs. C. PAC controllers are better than PLC controllers. D. None of the above.
D. None of the above.
Microprocessor units (MPUs) use an octal transceiver to enable ROM, RAM, I/O port devices, and support chips. TRUE OR FALSE
FALSE
Static RAM (SRAM) stores data in the form of charge on capacitors. TRUE OR FALSE
FALSE
A discrete PLC output module can be connected to ____. A. sensors B. pilot lights, solenoids, or motors C. the computer D. All of the above.
B. pilot lights, solenoids, or motors
Which of the following statements is false? A. EPROM can be programmed several times. B. EEPROM can be programmed several times. C. Flash ROM can be programmed several times. D. Masked ROM can be programmed several times.
D. Masked ROM can be programmed several times.
The ______________________________ in the microprocessor is used to carry out math and logic instructions.
Arithmetic logic unit ALU
To physically isolate the CPU from the input device, a(n) ______________________________ is used to input the DC signal to the CPU board.
Optoisolator
A sourcing output device must be connected to a(n) ______________________________ output module port
sinking
A(n) ______________________________-based microprocessor typically uses only one instruction for a complex command.
Reduced Instruction Set Computer RISC
Discrete input ports are ports that are either open (off) or closed (on). TRUE OR FALSE
TRUE
One benefit of PLCs over electromechanical relay logic systems is PLCs require minor wiring and can be modified and reprogrammed within a few hours. TRUE OR FALSE
TRUE
Read only memory (ROM) holds the permanent system program. TRUE OR FALSE
TRUE
You can place two or more input instructions in series in a PLC ladder logic rung. TRUE OR FALSE
True
A(n) ______________________________ is a sequential digital device that generates a different output for every input on the next clock pulse.
flip-flop
A unit for measuring the speed of serial communication transmission is the ______________________________ rate.
Baud
Programmable logic controllers are used to control ____. A. robots B. electric motors C. conveyors D. All of the above
D. All of the above
Allen-Bradley industrial controllers are grouped as ____. A. Programmable Logic Controllers B. Programmable Automation Controllers C. Safety Programmable Controllers D. All of the above.
D. All of the above.
Which of the following statement(s) is true? A. The input layout has an octal transceiver. B. The input port layout has a rectifier. C. The input port layout has a Zener diode. D. All of the above.
D. All of the above.
Changing relay logic requires ____. A. rewiring the relays B. changing input port names C. changing output port addresses D. None of the above
A. rewiring the relays
A(n) ______________________________ converts the analog input signals to binary digital signals.
ADC
Allen-Bradley PLC's backplane delivers ____. A. only power to input/output modules B. power and communication signals to input/output modules C. only communication signals to input/output modules D. All of the above.
B. power and communication signals to input/output modules
Simplex channeling occurs when the DTE either transmits data to or receives data from the DCE. TRUE OR FALSE
TRUE
Which one of the following Allen-Bradley PAC controllers has a 32-bit processor? A. Compact logix B. Control logix C. Soft logix D. All of the above.
D. All of the above.
Which Rockwell Automation software can be used to program one or more Allen-Bradley PLC or PAC devices? A. RS Logix 500 B. RS Logix 5000 C. RS Linx D. Both A and B
D. Both A and B
In half duplex channeling, the DTE transmits data to and receives data from the DCE through two separate transmission lines. TRUE OR FALSE
FALSE
An address number writes over the instruction description for an Input or Output instruction. TRUE OR FALSE
False
The software that resides in ROM is called ______________________________.
Firmware
The ______________________________ Allen-Bradley SLC 500 PLCs give you the option of chassis, power supply, processor, and I/O modules.
modular
A(n) ______________________________ check is used to find transmission errors due to lost or changed bits.
parity
The instruction with address O:2/0 represents the PLC output port ______ in the PLC module ____ .
0, 2
Allen-Bradley SLC 500 PLCs have Channel ______________________________ and Channel ______________________________ that can be used for communications.
0,1 or 1,0
The instruction with address I:1/2 represents the PLC input port ______ in the PLC module _____.
2, 1
Which of the following statements is false? A. The output port layout has an optoisolator. B. The output port converts digital signal to analog signal. C. The output port layout always requires two octal latches. D. None of the above
C. The output port layout always requires two octal latches.
Same output address instructions may be used two or more times in a PLC ladder logic diagram. TRUE OR FALSE
False
You can place two or more output instructions in series in a PLC ladder logic rung. TRUE OR FALSE
False
You can place two or more output instructions in series or parallel with each other in a PLC ladder logic rung. TRUE OR FALSE
False
How many output instructions you can place in series in a ladder logic diagram?
None
What type of instruction you must place as a last instruction on a rung of a ladder logic diagram?
Output
SLC is an acronym for ______________________________.
Small logic controller
The ______________________________ is a rack that serves as an electrical backplane for a PLC.
chassis
The three different types of PLC programming modules are handheld, dedicated, and ______________________________.
computer
What are the four major components of a PLC device?
cpu, power supply, input/output modules and chassis
A ____ converts the digital output signals back to analog signals. a. bus b. register c. triac d. digital-to-analog converter
d. digital-to-analog converter
A sinking input device must be connected to a(n) ______________________________ input module port
sourcing
TTL is an acronym for ______________________________.
Transistor-Transistor Logic
In a PLC ladder logic rung, the last instruction must be an output instruction. TRUE OR FALSE
True
A field device is connected to an input module in slot 4 at terminal 9, what is the correct SLC 500 address? A) I:4/9 B) I/4:9 C) I:9/4 D) I/9:4
A) I:4/9
Which of the following statements is NOT correct? A) The cost and size of PLCs have increased significantly in the last 10 years. B) The physical wires between the input and output field devices and the PLC input and output modules are the only signal wires required in the PLC system. C) If a problem in a PLC module occurs, the module can be changed in a matter of minutes without any changes in wiring. D) Outputs can be paralleled on the same rung.
A) The cost and size of PLCs have increased significantly in the last 10 years.
All PLC and PAC power supplies must provide ____. A. 5 volts B. 10 volts C. 5 and 10 volts D. 5 and 24 volts
A. 5 volts
Which of the following statements is true? A. Data terminal equipment (DTE) initiate communication in the network. B. Data communication equipment (DCE) initiate communication in the network. C. In a simplex system, DCE either transmits or receives signals. D. None of the above.
A. Data terminal equipment (DTE) initiate communication in the network.
The first PLC was built by ____. A. General Motor B. Allen-Bradley C. Siemens D. IBM
A. General Motor
Which checking method is used to detect data transmission error in PLC communication? A. Parity B. BCD C. HEX D. None of the above.
A. Parity
How many input instructions you can place in series in a ladder logic diagram?
As many as the PLC memory capacity allows
Which of the following statements is NOT correct? A) Input (-| |-) and output (- ( ) -) instruction symbols in the ladder logic represent only data values stored in PLC memory. B) PLCs are not as reliable as electromechanical relays in RLL. C) The status of each input can be checked from one location and outputs can be forced on and off. D) All symbols in the RLL represent actual components and contacts present in the control system
B) PLCs are not as reliable as electromechanical relays in RLL.
Which of the following statements is correct? A) A ladder logic program is hard to analyze because it is totally different when compared with the equivalent relay logic solution. B) The number of ladder logic virtual relays and input and output instructions is limited only by memory size. C) Ladder logic is a PLC graphical programming technique introduced in the last 10 years. D) The number of contacts for a mechanical relay is limited to number of coils on the relay.
B) The number of ladder logic virtual relays and input and output instructions is limited only by memory size.
When a relay is NOT energized: A) There is an electrical path through the NO contacts. B) There is an electrical path through the NC contacts. C) Neither the NO or the NC contacts have an electrical path. D) Both the NO and the NC contacts have an electrical path
B) There is an electrical path through the NC contacts.
PLCs are ________ designed for use in the control of a wide variety of manufacturing machines and systems. A) electromechanical systems B) special-purpose industrial computers C) personal computers D) All of the above
B) special-purpose industrial computers
Which of the following statements is false? A. All Allen-Bradley PLCs have power supply and central processing units B. All Allen-Bradley PLCs have Analog-To-Digital (ADC) and Digital-To-Analog (DAC) Ports C. All Allen-Bradley PLCs have discrete input/output ports D. All Allen-Bradley PLCs have communication channels
B. All Allen-Bradley PLCs have Analog-To-Digital (ADC) and Digital-To-Analog (DAC) Ports
Which one of the following network system is more popular in industry? A. DeviceNet B. Ethernet C. ControlNet D. Data Highway Plus (DH+)
B. Ethernet
The scan cycle for a standalone PLC has ____. A. read input devices and updates output devices B. read input devices, executes the LLD program, and updates output devices C. read input devices and communication channels D. read input devices, executes the RLD, and updates output devices
B. read input devices, executes the LLD program, and updates output devices
When you consider purchasing a PLC or a PAC, the term "expandability" means you can ____. A. upgrade the CPU B. upgrade the current capability of the PLC power supply C. change the input/output voltage level D. send the PLC to the manufacturer for repair
B. upgrade the current capability of the PLC power supply
The ____ segment holds the PLC ladder logic diagram. A. system memory B. user memory C. serial communication D. simplex
B. user memory
BIOS is an acronym for ______________________________.
Basic input/output system
PLCs are designed to replace ____. A. microprocessors B. microcontrollers C. electromechanical relay panels D. desktop computers
C. electromechanical relay panels
Which of the following statements is not correct? A) Input and output instructions in ladder logic do not directly represent the switches and actuators. B) The PLC rung output [-( )-] is a discrete output instruction or bit in memory. C) Each rung of the ladder logic represents a logical statement executed in software inputs on the right and outputs on the left. D) PLC input instructions are logical symbols associated with voltage at the input module terminals.
C) Each rung of the ladder logic represents a logical statement executed in software inputs on the right and outputs on the left.
On SLC 500 models the processor is placed in: A) The last slot. B) Slot 0 or the middle slot if it is a 10 slot rack. C) Next to the power supply. D) Any slot.
C) Next to the power supply.
Which of the following statements is false? A. All PLC and PAC controllers have Timer and Counter functions. B. All PLC and PAC controllers have Sequencer functions. C. All PLC and PAC controllers have High Speed Counters. D. All of the above statements are correct.
C. All PLC and PAC controllers have High Speed Counters
Which communication protocol is the fastest? A. Full Simplex B. Half Duplex C. Full Duplex D. Simplex
C. Full Duplex
Which of the following statements is false? A. Optoisolators are used to protect CPU from high voltage in the input port B. Optoisolators are used to protect CPU from a short circuit in the output port C. Optoisolators are used to protect the input/output devices D. Optoisolators are used to isolate the CPU from input/output ports
C. Optoisolators are used to protect the input/output devices
When you consider purchasing a PLC or a PAC, the term "flexibility" means you can ____. A. change the CPU B. expand the power supply C. change the input/output voltage level D. add more input/output ports
C. change the input/output voltage level
For small control projects in harsh environments, use the ____ industrial control system. A. PLC B. PAC C. relay logic D. None of the above.
C. relay logic
. Baud rate measures ____. A. the speed of parallel data transmission B. microprocessor is clock speed C. the speed of serial data transmission D. None of the above.
C. the speed of serial data transmission
An SLC 500 output address is O:2/10, what slot is the module in and what terminal is used for the connection? A) Slot 10 and terminal 2 B) Slot 2 and terminal 12 C) Slot 12 and terminal 2 D) None of the above
D) None of the above
A PLC programming module (PM) can be a ____. A. desktop computer B. hand-held programmer C. laptop computer D. All of the above.
D. All of the above.
A microprocessor has a(n) ____. A. arithmetic logic unit (ALU) B. decode unit C. data and instruction cache D. All of the above.
D. All of the above.
Which of the following statements is true? A. PLC design is similar to Personal Computer (PC) design B. A Personal Computer (PC) can be used for process control C. PLC is used for number-crunching in industrial control systems D. PLC is used as an event-driven controller
D. PLC is used as an event-driven controller
Digital, or variable, output modules use ______________________________ ICs to convert digital data supplied by the PLC processor to scalable voltage or current output.
DAC
In communication systems, DTE stands for ______________________________.
Data Terminal Equipment
In communication systems, DCE stands for ______________________________.
Data communication equipment
EPROM is an acronym for ______________________________.
Erasable programable read only memor
Can the same input or output instruction be used more than one time in a ladder logic diagram?
Input Yes Output No
SRAM uses a(n) ______________________________ to hold a data bit
Internal Flip-Flop
How many factors would you consider for selecting a PLC? List them
Technical: support, flexibility, timing, documentation Economic: initial costs, warranty, service charges, cot of memory, I/O expansion
Same input address instructions may be used two or more times in a PLC ladder logic diagram. TRUE OR FALSE
True
UVEPROM is an acronym for ______________________________.
Ultraviolet erasable programmable read only memory
A(n) ______________________________ diode is a semiconductor device that can maintain a steady voltage level.
Zener
A(n) ____ is a semiconductor device that can maintain a steady voltage level. a. zener diode b. optoisolator c. flip-flop d. full-wave rectifier
a. zener diode
A microprocessor unit (MPU) uses a(n) ______________________________ to enable ROM, RAM, I/O port devices, and support chips.
address decoder
The ____ segment holds the ladder logic program. a. system memory b. user memory c. serial communication d. Simplex
b. user memory
The four major components of a PLC power supply are a line conditioner or varistor, transformer/rectifier unit, RC filter, and ____. a. valve b. fixed PLC c. zener diode d. Microprocessor
c. zener diode
The ______________________________ instruction allows the system to run and allows the program to be modified while the system is running.
remote/run program
A(n) ____ is a unidirectional semiconductor device that can maintain a steady voltage level. A. Zener diode B. optoisolator C. flip-flop D. full-wave rectifier
A. Zener diode
PLCs were first introduced in the ____. A. automotive industry B. power industry C. process industry D. None of the above
A. automotive industry
For modular SLC 500 PLCs, you can ____. A. expand the size of the rack up to 30 slots B. expand the size of the rack up to 60 slots C. never expand the size of the rack D. expand the rack size as much as you want
A. expand the size of the rack up to 30 slots
Which of the following industrial controllers has the most features? A. PLC B. PAC C. DCS D. RTU
B. PAC
If all the units are in one enclosure, the PLC is called a ____ PLC. A. modular B. fixed C. discrete D. None of the above.
B. fixed
. The section of the PLC system memory that holds the status of discrete input ports is the ____ status. A. counters' B. input C. timers' D. output
B. input
Ports that are either open (off) or closed (on) are ______________________________ input ports.
Discrete
Which part of the PLC occupies more memory than the rest? A. Timers and counters memory area B. Advance functions memory area C. User memory area D. Input and output images memory area
C. User memory area
The four major components of a PLC power supply are a line conditioner or varistor, transformer/rectifier unit, RC filter, and ____. A. valve B. fixed PLC C. Zener diode D. microprocessor
C. Zener diode
A(n) ______________________________-based microprocessor uses several math instructions to carry out complex commands.
Conventional Instruction Set Computer CISC
Static RAM ____. A. requires more space than dynamic RAM on the PLC motherboard B. is more expensive than dynamic RAM C. requires more transistors and has faster response than dynamic RAM D. All of the above
D. All of the above
Which of the following is important criteria when you are selecting a PLC or a PAC controller? A. Programming software cost B. Initial cost of the PLC or the PAC controller C. Flexibility and expandability of the PLC or the PAC controller D. All of the above
D. All of the above
. Which of the following method(s) may be used to program PLCs? A. Ladder Logic Diagram (LLD) programming B. Function block programming C. Text programming D. All of the above.
D. All of the above.
A(n) ____ converts the digital output signals to analog signals. A. bus B. register C. ADC D. DAC
D. DAC
In a "framed" word, there are ____. A. start bit and data bits B. stop bit and data bits C. only data bits D. start, stop, and data bits
D. start, stop, and data bits
Output ports that are either energized (on) or de-energized (off) are ______________________________ output ports.
Discrete
What is the difference between a discrete PLC input port and a variable PLC input port?
Discrete input port is either open or closed Variable input has variable input voltage or variable input current
DRAM is an acronym for ______________________________.
Dynamic random access memory
In half-duplex channeling, the DTE transmits data to and receives data from the DCE through two separate transmission lines. TRUE OR FALSE
FALSE
The user memory segment stores information needed to execute the user program. TRUE OR FALSE
FALSE
What is the difference between a Fixed PLC system and a Modular PLC system?
In fixed PLCs cpu, power supply, input ports, and output ports are in one housing In modual plc; cpu, power supply, input and output ports are in separate slots
SRAM is an acronym for ______________________________.
Static random access memory
The use of ______________________________ enables a microprocessor to communicate with I/O devices.
Support chips
What is the difference between system PLC memory and user PLC memory?
System memory holds d(?) for program execution and user memory holds the PLC program
Sourcing occurs when the current flows out of the PLC port and sinking occurs when the current flows into the PLC port. TRUE OR FALSE
TRUE
The arithmetic logic unit (ALU) carries out math and logic instructions. TRUE OR FALSE
TRUE
When selecting PLCs that meet your needs, you should consider manufacturer's support, serviceability, and programming software. TRUE OR FALSE
TRUE
When selecting a PLC to meet your needs, you should consider manufacturer's support, serviceability, and programming software. TRUE OR FALSE
TRUE
If all the units are in one fixed enclosure, the PLC is called a ____ PLC. a. modular b. fixed c. discrete d. None of the above.
b. fixed
The section of the PLC system memory that holds the status of discrete input ports is the ____ status. a. counters' b. input c. timers' d. output
b. input
The MPU uses ______________________________ memory to speed up the data transfer while it is executing a program.
cashe
