1. Programmable Logic Controllers
Test #1

2. Numerical control equipment Microcomputers. Analog controllers.
1. PC’s were originally designed as replacements for: a.
Relay logic. c.
Numerical control equipment b.
Microcomputers. d.
Analog controllers.
2. Binary Logic: a.
is described only by ladder diagrams c.
does not work for a three-input AND b.
has two states only d.
has more than two states
3. To produce a logic 1 from a NOR operation, the inputs must be: a.
1 and 1 c.
0 and 0 b.
0 and 1 d.
1 and 0
4. Most PC’s have the same basic set of components. Which of the following is correct? a.
I/O, memory, processor, programming language, programming tool, power supply, housing. c.
I/O, diagnostics, processor, power supply, memory, housing b.
I/O, CRT terminal, processor, ladder diagram, power supply, housing. d.
I/O, memory, programming tool, data highway, Boolean statements, power supply, housing.
5. The control plan stored in a PC is called: a.
A microprocessor c.
A program. b.
FORTRAN d.
A Boolean ladder.

3. 219 Convert binary number 11011011 to a decimal number.
Binary numbers use a place-weighting system. The place weights for binary:
219 a.
Increase by adding 2 for each place, starting with 0 c.
Start with 2 and double for each successive place b.
start with 1 and are successive powers of 2 d.
Increase by adding 2 for each place, starting with 2.
8. The processor unit: a.
looks at the output interface, makes the decision provided by the program, and sets the input interface. c.
looks at the input interface, makes the decision provided by the program, and sets the output interface. b.
understands only ladder logic d.
serves only to store the program in memory.
9. The input interface: a.
connects the CPU to signals from the process. c.
Allows the CPU to input messages to a CRT screen b.
allows the programmer to input the program d.
provides inputs to motor controllers and similar field devices.
10. Data concerning external contact closure in a PC system is brought in by the input interface and stored in memory. The storage device is called: a.
ROM c.
The programming tool b.
a register. d.
A program.

4. 11. The decimal number 15 would be written in binary as: c.
1111 b. F d.
1000
12. To produce a logic 0 from a NAND operation, the inputs must be: a.
0 and 1 c.
1 and 1 b.
0 and 0 d.
1 and 0
5325
13. Convert hexadecimal number 14CD into a decimal number
14. Convert decimal number 232 into an octal number
350
15. To produce a logic 0 from an OR operation, the inputs must be. a.
1 and 1 c.
1 and 0 b.
0 and 1 d.
0 and 0
16. Normally, when a process contact connected to the input closes: a.
this starts the CPU in operation c.
the internal contact with the correct address is given a logic 1 condition and is considered to be closed b.
a logic 0 is recorded in memory d.
the coil with the same address is given a logic 1 condition.

5. 17. When the program scan occurs:
the condition of all process contacts connected to the input interface is controlled by the CPU c.
the condition of all process contacts connected to the input interface is recorded in memory. b.
the condition of all process contacts connected to the input interface is controlled by the output logic d.
the condition of all process contacts connected to the input interface depends on the program.
Convert Binary Coded Decimal (BCD) number into a decimal number
539
19. The programming tool: a.
is always a CRT screen device c.
Is used to unscrew the case of the PC and replace the memory chips b.
is the device used by the programmer to bring the process signals into the output interface d.
allows the programmer to enter the program into the PC
20. The binary number 111 has the decimal equivalent: a. 3 c. 61 b.
111 d. 7
21. A ladder logic program cannot be designed to: a.
specify outputs to be set. c.
specify inputs to be examined. b.
change the contents of ROM d.
make comparisons between data

6. 101100111 provides data for the CPU/memory to analyze.
22. The output interface: a.
provides data for the CPU/memory to analyze. c.
connects the processor unit to the process and produces the control signals b.
allows the program in memory to be output to the CPU d.
None of the above
23.
The --| |-- symbol in a ladder diagram: a.
is always at logic 1 c.
represents a normally open contact b.
represents a normally closed contact d.
represents a capacitor
24. To produce a logic 1 from an AND operation, the inputs must be: a.
0 and 0 c.
1 and 0 b.
0 and 1 d.
1 and 1
25. The two fundamental types of memory used in PC’s are: a.
RAM and ROM. c.
Magnetic RAM and tape b.
CPU and I/O interface d.
Tape and disc.
26. Convert decimal number 359 into a binary number