Integral Control (Automatic Reset), I - Siemens Milltronics BW500 Operating Lnstructions

The control output cannot reach the setpoint using only the
on the difference between the setpoint and process variable, a small difference between
these two always exist and the difference is never zero. A small
process very close to set point, but it would take a very long time. At the very least, an I
term is required to eliminate the offset created by the

Integral Control (Automatic Reset), I

The I term on the BW500 is used to increase or reduce the amount of control output to
eliminate the offset caused by the
error over small increments of time. As the process reaches setpoint and the error
becomes small, the effect of the I term decreases. A higher I term makes the BW500
faster to react to changes, but can also make it less stable.
• allowable input range:
• typical operating range:
• default value:
P
The and I terms together can make a suitable control algorithm and for many
applications, they work fine. However, if faster response to changes is desired, it is
necessary to use larger
unstable. A derivative term is needed to influence the control output as the process
variable approaches the set point.
7ML19985DK05Milltronics BW500 and BW500/L - OPERATING INSTRUCTIONS
P
term. The I term acts on the
0.000 to 2.000
0.100 to 0.300
0.200
P
and I terms. Unfortunately, larger terms can make the system
P
term. Since the
P
term can get the
P
term.
accumulation
P
term acts
of the
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