Radian (RAD)
This table lists the controllers and applications that support this instruction.
Architecture | Standard applications | Safety applications |
|---|---|---|
CompactLogix 5370, ControlLogix 5570, Compact GuardLogix 5370, and GuardLogix 5570 controllers | Yes | No |
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers | Yes | Yes |
When enabled, the RAD instruction converts the Source (in degrees) to radians and stores the result in the Destination.
Available Languages
Ladder Diagram
Function Block Diagram
Function Block Diagram supports these elements:
FBD Block
FBD Function
TIP:
FBD Function is applicable to CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers only.
Structured Text
This instruction is not available in structured text.
TIP:
Use RAD as an operator in an expression to compute the same result. Refer to for more information on the syntax of expressions and assignments within structured text.
Operands
IMPORTANT:
Unexpected operation may occur if:
- Output tag operands are overwritten.
- Members of a structure operand are overwritten.
- Except when specified, structure operands are shared by multiple instructions.
There are data conversion rules for mixing numeric data types within an instruction. See Data conversions.
Ladder Diagram
Operand | Data Type CompactLogix 5370, ControlLogix 5570, Compact GuardLogix 5370, and GuardLogix 5570 controllers | Data Type CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers | Format | Description |
Source | SINT INT DINT REAL | SINT INT DINT LINT USINT UINT UDINT ULINT REAL LREAL | Immediate tag | Value to convert to radians |
Destination | SINT INT DINT REAL | SINT INT DINT LINT USINT UINT UDINT ULINT REAL LREAL | tag | Tag to store the result |
Function Block Diagram
FBD Block
Operand | Type | Format | Description |
RAD | FBD_MATH_ADVANCED | tag | RAD structure |
FBD Function
TIP:
FBD Function is applicable to CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers only.
Input Operands (Left Pins) | Data Type CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers | Description |
Source | SINT INT DINT LINT USINT UINT UDINT ULINT REAL LREAL | Value to convert to radians |
Output Operand (Right Pin) | CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers Data Type | Description |
Dest | REAL LREAL | Result of the function. |
FBD_MATH_ADVANCED Structure
Input Members | Data Type | Description |
EnableIn | BOOL | Enable input. If false, the instruction does not execute and outputs are not updated.
Default is true. |
Source | REAL | Input to the conversion instruction. |
Output Members | Data Type | Description |
EnableOut | BOOL | Indicates if the instruction executed without fault when it was enabled. |
Dest | REAL | Result of the instruction. |
Description
The RAD instruction uses this algorithm:
Deg2RadConvFactor=pi/180= 0.017453292
Destination = Source * Deg2RadConvFactor
Affects Math Status Flags
Controllers | Affected Math Status Flags |
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers | Conditional, see Math Status Flags. |
CompactLogix 5370, ControlLogix 5570, Compact GuardLogix 5370, and GuardLogix 5570 controllers | Yes |
Major/Minor Faults
None specific to this instruction. See Index Through Arrays for array-indexing faults.
Execution
Ladder Diagram
Condition/State | Action taken |
Prescan | N/A |
Rung-condition-in is false | Set Rung-condition-out to Rung-condition-in. |
Rung-condition-in is true | Set Rung-condition-out to Rung-condition-in. Dest = radian value of the Source. |
Postscan | N/A |
Function Block Diagram
FBD Block
Condition/State | Action Taken |
Prescan | N/A |
EnableIn is false | Set EnableOut to EnableIn. |
EnableIn is true | Dest = radian value of the Source. If overflow occurs Clear EnableOut to false. else Set EnableOut to true. |
Instruction first scan | N/A |
Instruction first run | N/A |
Postscan | N/A |
FBD Function
Condition/State | Action Taken |
Prescan | N/A |
Normal Scan | Dest = RAD(Source) |
Instruction first run | N/A |
Instruction first scan | N/A |
Postscan | N/A |
Example
Ladder Diagram
Function Block Diagram
FBD Block
FBD Function
Structured Text
REAL_dest := RAD(REAL_src);
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