IDIS 400
Define the term analog
a rang of values (non discrete)
Contacts wired in parallel have what relationship?
OR
Briefly describe the EXAMINE ON instruction.
examines a value of another location and returns the input value as is. True --> True
Draw an AC output module with four devices
figure 2-16 pg. 24
List the two types or styles of programming devices
handheld or PC
define word
two bytes or 16 bits
what is the function of the LED within the optical isolator?
indicates to the photo transistor that the system is active. This sends the ON signal to the PLC system.
what is the function of the diodes within the AC and DC discrete input module?
insure that the current only flows one way. also status light.
state two reasons for employing optical isolation
isolate high voltages reduces noise
Define the terms normally open and normally closed
normally open - off when de-energized normally closed - on when de-energized
How do we prevent binary numbers 10 and 11 from being confused as decimal numbers?
parenthesis and subscripts (10)_2 and (11)_2
Explain what "+" and "-" represent
positive and negative inputs in a DC circuit
The two main vertical lines of a ladder diagram are often referred to as:
rails
Define Interface
converts input signal to output signal voltage drop from 24 or 110 to 5 V
The hexadecimal value 2CB is not which of the following a. 715 decimal b. 1313 octal c. 0010 1100 1011 binary d. 0111 0001 0011 BCD
d. 0111 0001 0011 BCD
what are the function of R1 and R2 in an AC Discrete Input module?
reduces the input voltage
The horizontal lines of a ladder diagram are often referred to as:
rungs
Explain why there is no filter network
the system is already input as DC
List the Four Main components of a PLC.
1. Input module 2. output module 3. cpu 4. memory
Convert decimal number 359 to a binary number.
101100111
1K of memory is actually: How many words?
1024 words
Convert binary number 11011011 to a decimal number.
219
Convert decimal number 232 to an octal number.
350
Convert hexadecimal number 14CD to a decimal number.
5325
define byte.
8 bits.
Contacts wired in series have what relationship?
AND
what are the function of R1 and R2 in an DC Discrete Input module?
reduce the input voltage
when information is stored using only 1s and 0s, it is called a _______ system.
Binary
A bit is an acronym for a ________
Binary Digit
The decimal numbering system uses 10 digits, or a base of 10. List the base for each of the following numbering systems. Binary: Hexidecimal: Octal:
Binary: 2 Hexidecimal: 16 Octal:8
The processor is often referred to as the __________ of the programmable controller.
Brain
Convert decimal number 3247 to a hexadecimal number.
CAF
How are contacts that are associated with relays, motor starters timers and the like identified?
CR1, M2, T1.DN, etc.
What is the function of a Bridge Rectifier?
Converts AC input voltage to DC
Explain the following initials: DC ADC AC CPU DAC PC PLC NEMA I/O
DC - Direct Current ADC - Analog to Digital Converter AC - Alternating Current CPU - Central Processing Unit DAC - Digital to Analog Converter PC - Personal Computer PLC - Programmable Logic Controller NEMA - National Electrical Manufacturers Association I/O - Input/Output
The XIC instruction is the same as: a. EXAMINE ON b. EXAMINE OFF
EXAMINE OFF
The XIO instruction is the same as: a. EXAMINE ON b. EXAMINE OFF
EXAMINE ON
E-stop refers to:
Emergency - Stop
Identify the following PLC-5 Files I O N S B T R F C
I - Input O - Output N - Integer S - Status B - Bit T - Time R - Control F - Floating Point C - Counter
Describe the purpose of the I/O section
Input/Output Input: converts input signals to PLC levels Output: converts PLC levels to output signals
Briefly describe why a hardwired emergency-stop circuit is recommended for PLC installations.
It allows power to be cut from the whole system, bringing everything to a stop to prevent harm to the system or to people.
Explain what L1 and L2 represent.
L1 is the input power source in an AC circuit L2 is the ground point in an AC circuit
Define Discrete
Only has two options. -On/Off -True/False no inbetween
Devices that are intended to perform a START function are normally wired in ______ with each other.
Parallel
Devices that are intended to perform a STOP function are normally wired in ______ with each other.
Series
Briefly describe volatile memory.
System loses info when power turns off.
Briefly describe non-volatile memory.
System retains info when power turns off.
True or False RELAY LADDER LOGIC is a high level graphic computer language.
True
What is a major advantage of a PLC system over the traditional hardwired control system?
When you want to change system functionality, you do not have to rewire, you only reprogram.
what is the function of the photo transistor within the optical isolator?
picks up the LED and sends the ON signal to the PLC system
Convert the following 8-bit signed #'s to decimal. a. 1111 0110 b. 0111 0110 c. 1111 1001 d. 0111 1001
a. -10 b. +118 c. -7 d. +121
Express the following signed decimal numbers in 2s complement. Use 8-bit words. a. (-)7 b. (-)4 c. (-)3
a. 1111 1001 b. 1111 1100 c. 1111 1101
Convert the following binary values to decimal. a. 10011000 b. 01100101 c. 10011001 d. 00010101
a. 152 b. 101 c. 153 d. 21
Convert the following BCD values to decimal. a. 1001 1000 b. 0110 0101 c. 1001 1001 d. 0001 0101
a. 98 b. 65 c. 99 d. 15
If the N.O. limit switch in Question 2 is programmed using an N.C. contact symbol (EXAMINE OFF), the instruction will be true when?
as long as the limit switch is open
define the term scope tags.
availability of a tag to the user programs.
The BCD value 1001 0011 0101 is not which of the following? a. 935 decimal b. 0011 1010 0111 binary c. 647 octal d. 3A7 hexadecimal
c. 647 octal
Define Real World
components outside the PLC i.e. switches, buttons, etc.
What is the function of a filter network in an AC Discrete Input module?
condition the DC and guard against electrical noise.
Briefly describe the action of the EXAMINE OFF instruction.
examines a value of another location and returns the opposite value. True --> False
Draw an AC input module with four devices.
figure 2-11 pg. 19
Explain why a DC discrete input module does not have a bridge rectifier?
the system is already running DC. No need for conversion.
When an N.O. limit switch is wired to an input module, and programmed using an N.O. contact symbol (EXAMINE ON), the instruction will be true when?
when the limit switch is closed
Describe the diference between a wiring diagram and a ladder (schematic) diagram.
wiring: physical location ladder: relative location for easy reading