<5. Functions>
84
IM 01E21A02-03EN
Example:
(1) When input = 0 to 10%, Damping time constant = 5 seconds, Dead time = 3 seconds,
and Rate limit value = 1%, the output for the step input is obtained as shown below.
F0421.ai
10%
1%
Step signal
Flow rate value
after rate limit
processing
63.2%
100
225
Dead time: 3 s
(a)
(b)
(c)
(d) Flow rate value
after damping
Input: 0 to 10%
Damping time constant: 5 s
Dead time: 3 s
Rate limit value: 1%
Number of signal samples
• In the condition above (1), the signal exceeds the rate limit value as compared with the
previous value; therefore, the response is set to 1%.
The actual output, which is damped, is processed as indicated with the solid line.
• Then, the flow rate value in the dead time is set to the “flow rate after damping calcu
signal of rate limit value (1%)”.
• The input signal does not return to the rate limit value or less within the dead time; therefore,
it is judged to be a flow rate signal at the time of (3).
• The output signal starts following the step signal along the damping curve.
The figure below shows an output example when a slurry noise occurs.
(2) When input = 0 to 10%, Damping time constant = 1 second, Dead time = 1 seconds,
and Rate limit value = 1%, the output for a slurry noise is obtained as shown below.
F0422.ai
+1%
-1%
Dead time: 1 s
Flow rate value after damping
Flow rate value
after rate limit
processing
Slurry noise
Time
Input: 0 to 10%
Damping time constant: 1 s
Dead time: 1 s
Rate limit value: 1%
In the figure on the left,
it is determined that the
slurries noise signal is
not a flow rate signal.
