PLCLogix 500 features 65 instructions and PLCLogix 5000 has 80 instructions. These instructions encompass all of the main programming commands associated with either the Logix 500 or 5000 PLC. The PLCLogix Instruction Set consists of the following groups of commands: Bit Instructions, Timer and Counter Instructions, Program Control, Compare, Math, Advanced Math, Move/Logical, Array Shift and Sequencer Instructions.
Select the instruction set by choosing either PLCLogix 500 or 5000 in the Instruction Set Groups shown below:
Examines a bit for an Off (cleared, low) condition.
OTE
Output Energize
When rung conditions are true, the OTE will either set or clear the data bit.
OTL
Output Latch
When enabled, the instruction signals to the controller to turn on the addressed bit. The bit remains on, regardless of the rung condition.
OTU
Output Unlatch
When enabled, it clears (unlatches) the data bit. The bit remains Off, regardless of rung condition.
ONS
One Shot
Enable/disable outputs for one scan when rung is true. The status of the storage bit determines whether this instruction enables or disables the rest of the rung.
OSR
One Shot Rising
This instruction is a retentive input instruction that triggers an event to occur once. It either sets or clears the output bit, depending on the storage bit status
OSR
One Shot Rising
This instruction is a retentive input instruction that triggers an event to occur once. It either sets or clears the output bit, depending on the storage bit status
OSF
One Shot Falling
This instruction either sets or clears the output bit, depending on the storage bitâ€™s status.
Timer and Counter Instructions
Mnemonic
Name
Symbol
Description
TON
Timer On Delay
A non-retentive timer that accumulates time when the instruction is enabled. The accumulated value is reset when rung conditions go false.
TOF
Timer Off Delay
A non-retentive timer that accumulates time when the rung makes a true-to-false transition.
RTO
Retentive Timer On
A retentive timer that accumulates time when the instruction is enabled. Retains its accumulated value when rung conditions become false.
TON
Count Up
An instruction that counts false-to-true rung transitions. It counts upward and the accumulated value is incremented by one count on each of these transitions.
TOF
Count Down
This instruction counts downward on each false-to-true rung transition. The accumulated value is decremented by one count on each of these transitions.
RTO
Retentive Timer On
A retentive timer that accumulates time when the instruction is enabled. Retains its accumulated value when rung conditions become false.
CTU
Count Up
An instruction that counts false-to-true rung transitions. It counts upward and the accumulated value is incremented by one count on each of these transitions.
CTD
Count Down
This instruction counts downward on each false-to-true rung transition. The accumulated value is decremented by one count on each of these transitions.
RES
Reset
This instruction is used to reset a timer, counter or control structure. The accumulated value of these instructions are cleared when the RES instruction is enabled.
Program Control Instructions
Mnemonic
Name
Symbol
Description
JSR
Jump to Subroutine
This instruction jumps execution to a specific routine and initiates the execution of this routine, called a subroutine.
SBR
Subroutine
Stores recurring sections of program logic.
RET
Return
Used to return to the instruction following the a JSR operation.
JMP
Jump to Label
Skips sections of ladder logic.
LBL
Label
Target of the JMP instruction with the same label name.
MCR
Master Cont. Res.
Used in pairs to create a program zone that can disable all rungs between the MCR instructions.
AFI
Always False
Disables all instructions on a rung.
NOP
No Operation
This instruction functions as a placeholder.
TND
Temporary End
When enabled, it lets the controller execute logic only up to this instruction.
IOT
Immediate Output
This instruction immediately updates the specified output data.
Compare Instructions
Mnemonic
Name
Symbol
Description
EQU
Equal
This instruction is used to test whether two values are equal. If Source A is equal to Source B, the instruction is logically true.
GEQ
Greater Than or Equal To
Determines whether Source A is greater than or equal to Source B. If the value at Source A is greater than or equal to the value at Source B, then the instruction is true.
GRT
Greater Than
This instruction is used to test whether one value (Source A) is greater than another value (Source B).
LEQ
Less Than or Equal To
Determines whether one value (Source A) is less than or equal to another (Source B).
LES
Less Than
This instruction determines whether Source A is less than Source B.
LIM
Limit
This instruction is used to test for values within the range of the Low Limit to the High Limit.
MEQ
Mask Equal To
Passes the Source and Compare values through a Mask and compares the results.
NEQ
Not Equal To
This instruction tests whether Source A is not equal to Source B.
Math Instructions
Mnemonic
Name
Symbol
Description
ADD
Add
Adds Source A to Source B and stores the result in the Destination.
SUB
Subtract
Subtracts Source B from Source A and places the result in the Destination.
MUL
Multiply
Multiplies Source A by Source B and stores the result in the Destination.
DIV
Divide
Divides Source A by Source B and places the result in the Destination.
MOD
Modulo
Divides Source A by Source B and stores the remainder in the Destination.
SQR
Square Root
Calculates the square root of the source and places the integer result in the Destination.
NEG
Negate
Changes the sign (+, -) of the Source and stores the result in the Destination.
ABS
Absolute
Takes the absolute value of the Source and places the result in the Destination.
CPT
Compute
Performs the arithmetic operations defined in the Expression and stores the result in the Destination.
Math Conversions
Mnemonic
Name
Symbol
Description
TOD
Convert to BCD
This instruction converts a decimal value to a BCD value and stores the result in the Destination.
FRD
Convert to Integer
Converts a BCD value (Source) to a decimal value and stores the result in the Destination.
DEG
Degrees
Converts the Source (in radians) to degrees and places the result in the Destination.
RAD
Radians
Converts the Source (in degrees) to radians and stores the result in the Destination.
TRN
Truncate
Removes the fractional part of the Source and places the result in the Destination.
Advanced Math Instructions
Mnemonic
Name
Symbol
Description
SIN
Sine
Takes the sine of the Source value (in radians} and places the result in the Destination.
COS
Cosine
Takes the cosine of the Source value (in radians) and places the result in the Destination.
TAN
Tangent
Takes the tangent of the Source value (in radians) and stores the result in the Destination.
ASN
Arc Sine
Takes the arc sine of the Source value and places the result in the Destination (in radians).
ACS
Arc Cosine
Takes the arc cosine of the Source value and stores the result in the Destination (in radians).
ATN
Arc Tangent
Takes the arc tangent of the Source value and stores the result in the Destination (in radians).
LN
Natural Log
Takes the natural log of the Source value and stores the result in the Destination.
LOG
Log to the Base 10
Takes the log base 10 of the Source value and stores the result in the Destination.
XPY
X to the power Y
Takes Source A (X) to the power of Source B (Y) and stores the result in the Destination.
Move/Logical Instructions
Mnemonic
Name
Symbol
Description
MOV
Move
Copies the Source (which remains unchanged) to the Destination.
MVM
Masked Move
Copies the Source to a Destination and allows segments of the data to be masked.
CLR
Clear
Clears all the bits of the Destination.
DTR
Data Transitional
Passes the Source value through a Mask and compares the result with the Reference value.
SWPB
Swap Byte Instruction
Rearranges the bytes of a tag and stores the bytes in the new order.
SWP
Swap Byte Instruction
Swaps the lower and higher bytes of a specified number of words.
BTD
Bit Field Distribute
Copies the specified bits from the Source, shifts the bits to the appropriate position, and writes the bits into the Destination.
AND
Bitwise AND
Performs a logical AND operation by using the bits in Source A and Source B and placing the result in the Destination.
OR
Bitwise OR
Performs a logical AND operation by using the bits in Source A and Source B and placing the result in the Destination.
XOR
Bitwise Exclusive OR
Performs a bitwise XOR operation using the bits in Source A and Source B and stores the result in the Destination.
NOT
Bitwise NOT
Executes a bitwise NOT operation by using the bits in the Source and placing the result in the Destination
Array Shift Instructions
Mnemonic
Name
Symbol
Description
BSL
Bit Shift Left
Shifts the specified bits within the Array one position left.
BSR
Bit Shift Right
Shifts the specified bits within the Array one position right.
COP
Copy File
Copies the value in the Source to the Destination.
FLL
File Fill
Fills elements of an array with the Source value, while the Source remains unchanged.
AVE
File Average
Calculates the average of a set of values.
FFL
FIFO Load
Copies the Source Value into a FIFO stack on successive false-to-true transitions.
FFU
FIFO Unload
Unloads the Source value from the first position of the FIFO and stores that value in the Destination.
LFL
LIFO Load
Copies the Source value to the LIFO.
LFU
LIFO Unload
Unloads the value at .POS of the LIFO and stores 0 in that location.
SRT
File Sort
Sorts a set of values in one dimension of the Array into ascending order.
STD
File Standard Deviation
Calculates the standard deviation of a set of values in one dimension of the Array and stores the result in the Destination.
SIZ
Size in Elements
Determines the size of a dimension of an array and stores the number of elements in the specified dimension of the array
SIZE
Size in Elements
Determines the size of a dimension of an array and stores the number of elements in the specified dimension of the array
Sequencer Instructions
Mnemonic
Name
Symbol
Description
SQI
Sequencer Input
Detects when a step is complete in a sequence pair of SQO/SQI instructions.
SQO
Sequencer Output
Sets output conditions for the next step of sequence pair of SQO/SQI or SQO/SQC instructions.
SQL
Sequencer Load
Loads reference conditions into a sequencer array.
SQC
Sequencer Compare
Detects when a step is complete in a sequence pair of SQO/SQC instructions. RSLogix 500 instruction, supported by PLCLogix.
PID Instruction
Mnemonic
Name
Symbol
Description
PID
Proportional Integral Derivative
Uses an algorithm to control physical properties based on a Process variable that stores input values and a Control variable that represents the output value.
AOI Instruction
Mnemonic
Name
Description
AOI
Add-On Instruction
A collection of logic that contains a commonly used function or algorithm and cabe combined into a single instruction and enhance or extend the capabilities of the built-in instruction set.
UDT Instruction
Mnemonic
Name
Description
UDT
User Defined Data Type
A convenient method of combining all the storage required for a particular function in a single location, and enables easier reuse of code.