Proportional Operation (P Operation) - Mitsubishi Electric MELSEC-Q series Programming Manual

Proportional operation (P operation)

The control method for proportional operation is described below.
• In proportional operation, an MV (manipulated value) proportional to the deviation (the difference between the set value
and process value) is obtained.
• The relationship between E (deviation) and the MV is expressed by the following formula: K
is called the "proportional gain".
E
MV=K
P
Condition
When proportional gain K is smaller
P
When proportional gain K is larger
P
• The proportional operation in step response with a constant E (deviation) is illustrated below.
• A certain error produced relative to a set value is called an offset. An offset is produced in proportional operation.
Proportional Operation
Control operation gets slower.
Control operation gets faster. However, hunting is more likely to occur.
4 FUNCTIONS OF PID CONTROL
is a proportional constant and
P
4.2 Functions of PID Control
4
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