Test 2 PLC
With a ControlLogix 1756-L62 processor, controllers can be placed in any slot, but it is not possible to place multiple controllers in the same chassis.
False
With the ON delay timer, the delay in contact operation begins before the timer coil has been energized, or turned ON.
False
As a general rule, all input devices, except STOP buttons, are wired ____________________.
N.O.
The function or functions of the processor that can be locked out with the key switch or by using passwords are fairly standard and are the same from PLC to PLC.
False
The jump instruction (JMP) tells the processor to jump over a portion of the program.
False
The number of times an input device can be addressed and used in a programmed circuit is limited to eight.
False
The way the processor scans the program is the same from PLC to PLC.
False
The wiring diagrams show the circuit in its simplest form.
False
When the N.C. symbol is programmed in a ladder diagram, any address that is actually ON becomes logically true and power can flow.
False
____________________ instructions will remain ON, or true, even when the MCR instruction is false.
Latching Relay
In standard relay control systems, a(n) ____________________ control is often used to control power to the entire circuit or just to selected rungs.
Master
Retentive timers (RTO) can be programmed to replace ____________________ timers.
Motor Driven
A branch circuit within a branch circuit is known as ____________________.
Nesting
A(n) ____________________ is defined as a group of connected logic elements used to perform a specific function.
Network
With a parallel output configuration, all of the outputs are ON or OFF at the same time, based on the ____________________.
Network Logic
Electrical devices or components are shown in their ____________________ condition on a ladder diagram.
Normal
When the N.C. symbol is programmed in a ladder diagram, the processor views it as a request to examine the address of the contact for a(n) ___________________ condition.
OFF
To prevent unauthorized On-Line programming, a key switch is provided, either on the programming device or on the processor, to restrict the access to a monitor-only mode, or to Off-Line and monitor-only mode.
True
When a hard-wired backup control circuit is used in conjunction with a PLC to control a motor, then the overload contact on the motor starter must be wired in series with the motor coil to provide protection for the motor under both means of control, PLC and hard-wired.
True
When circuit requirements demand more time than is available from a single timer, two or more timers can be programmed together.
True
When a timer uses the format used by the Allen-Bradley timer, the preset time can be programmed with any value from 0 to 16,000.
False
A typical PLC network limitation is ____________________ series contacts per line.
10
The ____________________ is also used when debugging a new or modified program.
AFI
The Output symbol with a (?) indicates that the symbol needs a(n) ____________________.
Address
To avoid confusion when reading electrical drawings with OFF delay contacts, it must be remembered that normal refers to the coil ____________________ it has been deenergized.
After
Programming two or more timers together to extend the timing range is called ____________________.
Cascading
In an RTO, bit 13 is known as the ____________________ bit.
DN
Because the processor views the N.O. contact instruction as a request to examine a given address for an ON condition, it is referred to as a(n) ___________________ instruction.
EXAMINE ON
A network constitutes one rung of a ladder diagram that starts at the right rail and ends at the left rail.
False
An MCR zone can be nested within another MCR zone.
False
By combining two NOT gates and an AND gate, we get a NAND gate.
False
It is common practice to wire the overload contacts to an input module.
False
Jumping backward does not add to the total scan time.
False
The EXAMINE OFF instruction is only logically true when the device referenced is ON, or open.
False
___________________ contacts in a motor control circuit control the path for current flow to the output.
Hard-Wired
The NOT gate is often referred to as a(n) ____________________.
Inverter
A PLC is normally programmed using a(n) ___________________ logic-type language.
Ladder
The ____________________ has been the "working language" of electricians and electrical engineers for many years.
Ladder Diagram
Whenever the processor sees an N.O. contact in the user program, it views the contact symbol as a request to examine the address of the contact for a(n) ___________________ condition.
ON
The RSLogix software gives a(n) ____________________—Use a Larger Power Supply warning when the mix of I/O requires a larger power supply than has been selected.
OVERLOAD
____________________ programming means that the program is being developed without being connected to the process or driven equipment.
Offline
When programming using a personal computer and specialized software, a(n) ____________________ may be used to limit the access to the processor program.
Password
MCRs are sometimes called Master Control ____________________ because they reset the output to zero or OFF.
Resets
A common problem in programs that have ____________________ timers is that the timer is not accumulating time, even though the timer rung is true.
Retentive
When entering addresses, the ____________________ can be used instead of the colon (:).
Semicolon
When an MCR instruction has been programmed with no logic element preceding the instruction, it is said to be programmed _____________________.
Unconditionally
Devices or components are shown in order of importance whenever possible in a ladder diagram.
True
Ladder logic is a good choice for a programming language because it closely resembles the way circuits are hard-wired.
True
Logic gates can be combined to create very complicated control logic.
True
MCRs are often used with circuits that have off-delay timers so the circuit can be shut down completely without waiting for the timers to time out.
True
Most PLCs are designed so that any input contact (N.O. or N.C.) or output coil can be Forced On or Off.
True
Once a program is complete, it should be tested while still in the Off-Line mode.
True
The basic pneumatic timing relay is designed so that additional instantaneous contacts may be added.
True
The easiest way to avoid nesting is to remember that all branches must start at a common point, and all of the branches must end at the same location.
True
The ladder diagram, also referred to as a schematic or elementary diagram, is used by the electrician or technician to speed their understanding of how a circuit works.
True
The one-shot instruction (ONS) is an input instruction that makes the rung true for just one program scan, based on a false-to-true transition of the instruction that precedes the one-shot instruction.
True
The retentive timer lets the timer START and STOP without resetting the accumulated value to 0.
True
There are many more applications and circuits that normally require two- or three-pole devices that now only require single-pole devices when programmed for a PLC.
True
The vertical power lines (rails) of the ladder diagram represent the ____________________ of the circuit.
Voltage potential or Voltage or Potential
The ____________________ shows the circuit wiring and its associated devices in their relative physical location.
Wiring Diagram