172-65710M-04 (SC-F71 Parameters/Functions) 23 Dec 2021
219
This deviation between the Set value (SV) and the stabilized temperature is called
“Offset.”
With a narrower proportional band the control result becomes closer to that of the
ON/OFF control (oscillatory).
With a wider proportional band the output is gradually reduced to stabilize quicker,
however, often with a larger offset.
Refer to 8.6 Controlling with ON/OFF Action for ON/OFF action.
Integral action
Proportional action provides more
stable control than ON/OFF
control, but causes offset. This
offset can be automatically
corrected by Integral action.
As long as deviation exists
between the Set value (SV) and
the Measured value (PV), the
Manipulated output value (MV) is
added according to the size of the
deviation until no deviation exists.
The strength of the Integral action
is expressed in the Integral time.
The Integral time is the time till the
Manipulated output value (MV) by
the Integral action gets equal to
that by the Proportional action.
The shorter the Integral time, the
stronger the integral effect is, and
the longer the weaker.
Derivative action
The Derivative action allows the Manipulated output value (MV) proportional to the
changing rate (speed) of the Measured value (PV) to be produced to prevent a
fluctuation of the Measured value (PV) before it happens.
The strength of the Derivative action is expressed in the Derivative time. The
Derivative time is the time until the Manipulated output value (MV) by the Proportional
action gets equal to the Manipulated output value (MV) by the Derivative action when
the Measured value (PV) changes at a constant rate.
The longer the Derivative time is, the stronger the Derivative effect is, and the shorter
the weaker.
The Derivative effect, if set too strong, produces large Manipulated output (MV)
against a small change of the Measured value (PV), thus causing hunting and
resulting in unstable control.
Summary of Contents for SC-F71
Page 17: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 16 ...
Page 18: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 17 Differential temperature control ...
Page 114: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 113 Setting procedure ...
Page 131: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 130 Setting procedure ...
Page 134: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 133 Setting procedure ...
Page 141: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 140 Setting procedure ...
Page 153: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 152 Setting procedure ...
Page 158: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 157 Setting procedure ...
Page 168: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 167 Setting procedure ...
Page 172: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 171 Setting procedure ...
Page 175: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 174 Setting procedure ...
Page 180: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 179 Setting procedure ...
Page 185: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 184 ...
Page 199: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 198 Setting procedure ...
Page 207: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 206 Setting procedure ...
Page 249: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 248 Setting procedure ...
Page 280: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 279 Setting procedure ...
Page 293: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 292 Checking PID values ...
Page 303: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 302 Setting procedure ...
Page 316: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 315 Setting procedure ...
Page 320: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 319 Setting procedure ...
Page 347: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 346 Operating procedure ...
Page 388: ...172 65710M 04 SC F71 Parameters Functions 23 Dec 2021 387 Setting procedure ...