Yokogawa ADMAG AXF - Manual (Page 37)

IM 1E10C1-E 5-18
5. FUNCTION AND DATA SETTINGS
5.5.14 Procedure of Selecting Special Application Items
• Only the special application (“n” items) shipped being unpublished.
In case the “n” items should be used, it can be set “55” in parameter No. “L02”.
The “n” items can be set “55” in parameter No. “L02”.
Displayed Description
Default: 00
Code
00
55 Accessible up to L parameters.
Accessible up to n parameters.
Content
5.5.15 Rate Limit
• This function is used to remove noise that cannot be removed by increasing the
damping time constant.
• In case unexpected noise from step signal or slurry is entered, a basis is set to
recognize that signal is flow rate or noise.
The recoginition depends on rate limit value (upper and lower limit) and dead time
(sampling time).
• Determination of rate limit value and dead time.
Rate limit value:
Determine the level to reduce output
fluctuation.
For example, reducing 2% or more
fluctuation by setting as 2% to
reduce. Dead time T
0
:
Please determine the dead time
depending on ouput fluctuation width.
In case of noise of which is longer
than the dead time, please set the
dead time longer.
2%
2%
T
0
T
0
• Signal processing procedures:
The function sets a certain upper and lower limit (rate limit value) for first order
delay response values of flow rate data obtained in a previous sampling. If currently
sampled flow rate data exceeds or goes below the limit is regarded as current flow
rate value. Signals whose protruding portions show the same trends during a certain
number of sampling times (dead time) are identified as flow rate signals.