Specifying Output Compensation
An Output Compensation data array tag may be specified via the
Logix Designer
application tag editor. The data type defines the specifics for each output bit by specifying the characteristics of each actuator. The array indices correspond to the output bit numbers. The number of the highest compensated output bit defines the minimum size of this array. Changes to the output compensation take effect immediately.This diagram shows the effect of the output compensation on the relationships between the axis, input, and output
Offset and Delay Compensation
The offset provides position compensation, while the latch and unlatch delay provides time delay compensation for the latch and unlatch operation. This diagram shows the effect of the compensation values on an Output Cam element.
The cam range is defined by the left and right cam positions of the Output Cam element. The compensated cam range is defined by the cam range, offset, and latch and unlatch offsets. The latch and unlatch offsets are defined by the current speed v.
Latch Offset = v * Latch Delay
Unlatch Offset = v * Unlatch Delay
The resulting compensation offset can actually be larger than the difference between cam start and cam end position.
This equation illustrates the effect of the compensation values on the duration of an Output Cam element
Compensated Duration = Duration + Latch Delay - Unlatch Delay
Mode Compensation
Depending on the selected mode, the compensated output bit is set according to this table.
Mode | Behavior | When |
Normal | The output bit is set | the output of the latch and unlatch operation becomes active. |
The output bit is reset | the output of the latch and unlatch operation becomes inactive. | |
Inverted | The output bit is set | the output of the latch and unlatch operation becomes inactive. |
The output bit is reset | the output of the latch and unlatch operation becomes active. | |
Pulsed | The output bit is pulsed | when the output of the latch and unlatch operation is active. The on-duty state of the pulse corresponds to the active state of the output bit. |
The output bit is reset | the output of the latch and unlatch operation becomes inactive. | |
Inverted and Pulsed | The output bit is pulsed | the output of the latch and unlatch operation is active. The on-duty state of the pulse corresponds to the inactive state of the output bit. |
The output bit is set | the output of the latch and unlatch operation becomes inactive. |
This diagram shows the effect of the mode, cycle time, and duty cycle on an output bit.
Output Compensation Array Checks
This output compensation array checks are used with the MAOC instruction.
If you select | Then | Instruction error |
a latch and unlatch delay combination that results in a compensated cam of less than minimum width | the width of the compensated cam is set to the minimum. | |
a mode less than 0 or greater than 3 | a Normal mode is considered | Illegal Output Compensation |
a duty cycle less than 0 or greater than 100 and the mode is set to Pulsed or Inverted and Pulsed | a 0 or 100 duty cycle is considered | |
a cycle time less than or equal to 0 and the mode is set to Pulsed or Inverted and Pulsed | the output bit is not pulsed | |
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