Title: EIC225 Ch 4 Test Pool
Course: Open EIC225 Programmable Controllers

Q: Normally, a binary 1 represents the presence of a signal, while a binary 0 represents the absence of a signal.
- True
- False
A: True

Q: All gates are devices that have one input with which they perform logic decisions and produce a result at one or more of their outputs.
- True
- False
A: False

Q: All inputs to an AND gate must be 1 to produce a 1 output.
- True
- False
A: True

Q: All inputs to a NAND gate must be 1 to produce a 1 output.
- True
- False
A: False

Q: Only one input to an OR gate must be 1 to produce a 1 output.
- True
- False
A: True

Q: All inputs to a NOR gate must be 1 to produce a 1 output.
- True
- False
A: False

Q: Inverting the output of an OR gate will result in creating a NOR gate.
- True
- False
A: True

Q: The AND function, implemented using switches, will mean switches connected in parallel.
- True
- False
A: False

Q: A two input OR function, expressed as a Boolean equation, would be Y= AB.
- True
- False
A: False

Q: Hardwired logic refers to logic control functions determined by the way devices are interconnected.
- True
- False
A: True

Q: Hardwired logic can be implemented using relays and relay schematics.
- True
- False
A: True

Q: Hardwired logic is fixed and is changeable only by altering the way devices are connected.
- True
- False
A: True

Q: Programmable control is based on logic functions that are programmable and easily changed.
- True
- False
A: True

Q: There is no difference between a relay schematic and a ladder logic program.
- True
- False
A: False

Q: On some PLCs, only one output is allowed per ladder logic rung.
- True
- False
A: True

Q: One of the most common PLC programming languages is ladder logic.
- True
- False
A: True

Q: Ladder logic is a graphical representation of a user program.
- True
- False
A: True

Q: The binary concept makes use of the fact that certain informal:
- can exist in one of two possible states.
- can be broken down into smaller units for easier analysis.
- can be divided into two or more categories.
- can be divided into two, or multiples of two, categories.
A: can exist in one of two possible states.

Q: A gate is a device that:
- allows current flow in one direction only.
- changes alternating current to direct current.
- performs a logical decision based on its inputs.
- performs a logical decision based on its outputs.
A: performs a logical decision based on its inputs.

Q: In conventional logic circuits, binary 1 represents:
- the presence of a signal.
- the occurrence of some event.
- a high voltage level.
- all of these.
A: all of these.

Q: The logic function(s) used by PI-Cs is (are):
- AND
- OR
- NOT
- all of these.
A: all of these.

Q: The basic rule for an AND gate is:
- if all inputs are 1, the output will be 1.
- if all inputs are 1, the output will be 0.
- if all inputs are 0, the output will be 1.
- both a and b.
A: if all inputs are 1, the output will be 1.

Q: The basic rule for an OR gate is:
- if one or more inputs are 1, the output is 1.
- if one or more inputs are 1, output is 0.
- if one or more inputs are 0, the output is 1.
- both b and c.
A: if one or more inputs are 1, the output is 1.

Q: The NOT function can be thought of as:
- a FALSE-to-TRUE converter.
- a changer of states.
- an inverter.
- all of these.
A: all of these.

Q: A NOT function is used when a logic 1 must ________ some device.
- activate
- deactivate
- switch
- light
A: deactivate

Q: The OR function, implemented using contacts, requires contacts connected in:
- series
- parallel
- series/parallel
- parallel/series
A: parallel

Q: The logic symbol shown is that of the:
- AND function.
- OR function.
- NOT function.
- NAND function.
A: OR function.

Q: The Boolean equation for the logic symbol is:
- Y= A + B
- Y= AB
- Y= A • B
- either b or c.
A: Y= A + B

Q: The logic symbol drawn is that of the:
- AND function.
- OR function.
- NOT function.
- NOR function.
A: AND function.

Q: The Boolean equation for the logic symbol is:
- Y= A+B+C
- Y = ABC
- Y= (AB)+C
- Y = (A –B)C
A: Y = ABC

Q: With reference to the logic circuit, the output Y will be at a logic 1 when:
- inputs A and B are logic 1.
- input A or B is logic 1.
- input A is at logic 1 and input B is at logic 0.
- input A is at logic 0 and input B is at logic 1.
A: input A is at logic 1 and input B is at logic 0.

Q: The logic symbol drawn is that of the:
- AND function.
- OR function.
- NOR function.
- NAND function.
A: NAND function.

Q: The truth table for the logic symbol is:
- (a)
- (b)
- (c)
- (d)
A: (b)

Q: The logic symbol drawn is that of the:
- NOT function.
- NOR function.
- NAND function.
- OR function.
A: NOT function.

Q: The Boolean equation for the logic symbol is:
- A = Y
- A=B
A: (a choice with no text)

Q: The Boolean expression for the logic circuit drawn is:
- Y = ABC
- Y=A+B+C
- Y = (A + B)C
- Y=AB+C
A: Y=AB+C

Q: The Boolean expression for the logic circuit drawn is:
- Y = (A B)(CD)
- Y= ABC + D
A: (a choice with no text)

Q: Which logic circuit represents the Boolean expression Y = A(BC+D)?
- (a)
- (b)
- (c)
- (d)
A: (a)

Q: Which logic circuit represents the Boolean expression
- (a)
- (b)
- (c)
- (d)
A: (b)

Q: The Boolean expression for the logic circuit is:
A: (a choice with no text)

Q: The Boolean expression for the logic circuit drawn is:
A: (a choice with no text)

Q: Which of the hardwired relay schematics is being implemented by the PLC program shown?
- (a)
- (b)
- (c)
- (d)
A: (b)

Q: A single rung of a ladder logic program is arranged with:
- input conditions connected from left to right, with the output at the far right.
- input conditions connected from right to left, with the output at the far left.
- the output in the center and the input conditions to the left and right of it.
- all input conditions in parallel and all output conditions in series.
A: input conditions connected from left to right, with the output at the far right.

Q: An AND gate operates on the same principle as:
- a series circuit.
- a parallel circuit.
- a series-parallel circuit.
- none of these.
A: a series circuit.

Q: An OR gate operates on the same principle as:
- a series circuit.
- a parallel circuit.
- a series-parallel circuit.
- none of these.
A: a parallel circuit.

Q: A NOR gate is:
- an AND gate with an inverter connected to the output.
- an OR gate with an inverter connected to the output.
- equivalent to a series circuit.
- equivalent to a parallel circuit.
A: an OR gate with an inverter connected to the output.

Q: The basic rule for an XOR function is:
- if one or the other, but not both, inputs are 1, the output is 1.
- if one or more inputs are 1, the output is 1.
- if one or more inputs are 1, the output is 0.
- if one or more inputs are 0, the output is 1.
A: if one or the other, but not both, inputs are 1, the output is 1.

Q: If you want to know when one or both matching bits in two different words are ON, you would use the logic instruction.
- AND
- XOR
- OR
- NOT
A: OR