This output is made up of a SERVO function with or without a copy of the actuator’s position.
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After a Split Range or Heat/Cool PID, only the SERVO with copy position is available.
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With this type of output, the loop controller output scale must be OUTi_INF and OUTi_SUP in the interval [ 0 , 100 ].
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Its output period is the task period.
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If the loop controller is in automatic mode, the SERVO output takes into account the new loop controller output value in each sampling period. In the other modes, it is in each cycle of the task.
Block Diagram of a SERVO Output with Position Copy
Block diagram of a Servo drive output branch with position copy (RCPY).
The SERVO function inputs are the output OUT_MAN of the loop controller and the position copy of the actuator RCPY.
When the SERVO output follows a Split Range or Heat/Cool function, the copy input is indispensable. SERVO function inputs are then OUT1 or OUT2 and RCPY.
Block Diagram of a SERVO Output without Position Copy
Block diagram of a Servo drive output branch without position copy (RCPY).
The Servo function entry is a variation of the OUTD command of the PID.
NOTE: OUTD is not affected by limiting output OUT_MAN. This can be used to perform a floating process control - the command calculated by the PID has no direct link with the actual position of the actuator. In particular, it is possible to continue opening or closing a motorized valve even when OUT_MAN is saturated.
