Pid (Pid Control) - IDEC MICROSmart FC6A Series Ladder Programming Manual

19: PID C
Introduction
This chapter describes the PID control instructions that perform auto tuning and PID control for temperature control and other purposes.

PID (PID Control)

Executes PID control and outputs that result. When auto tuning is performed, the optimal PID parameters (proportional
gain, integral time, and derivative time) and control action are automatically calculated.
This instruction is compatible with the FC5A Series MICROSmart PID instruction. When temperature control is performed
using the FC5A Series MICROSmart PID instruction, the same temperature control can be achieved by replacing it with the
FC6A Series MICROSmart and the FC6A Series MICROSmart PID instruction.
PID S1 S2
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Notes:
• The PID instruction and the PIDA instruction can be mixed in a single program, and a maximum of 32 instructions can be used.
• For details on the PID instruction, see Chapter 14 "PID Instruction" in the "FC5A Series MICROSmart Pentra User's Manual Advanced
Volume".
PIDA (PID Control)
Executes PID control and outputs that result. When auto tuning is performed, the optimal PID constants are calculated.
When auto/manual mode is switched, the balance-less and bumpless function automatically operates to prevent rapid
changes in the output manipulated variable.
A maximum of four alarm types, out of nine, can be set to detect process variable errors for multiple conditions.
PIDA S1
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Notes:
• The PID instruction and the PIDA instruction can be mixed in a single program, and a maximum of 32 instructions can be used.
• For details on the PIDA instruction, see "PIDA (PID Control)" on page 19-3.
PIDD (PID with Derivative Decay)
Executes PID control and outputs that result. The PID control parameters stored in the control registers are handled as data
type F (float), and fine adjustments can be made to the control parameters such as proportional gain, integral gain, and
derivative gain. Multiple PIDD instructions can also be combined to execute the cascade control.
PIDD ** S1
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Notes:
• A maximum of 32 PIDD instructions can be used in a user program. PID and PIDA instructions are counted separately.
• For details on the PIDD instruction, see "PIDD (PID with Derivative Decay)" on page 19-26.
I
ONTROL NSTRUCTION
S3 S4 D1
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S2 S3 S4
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S2 S3 SP PV
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FC6A S MICROS
ERIES MART
MV
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ADDER ROGRAMMING ANUAL
FC9Y-B1726 19-1