YOKOGAWA TB830D, User Manual, Page: 39 / 85

< 4. SETTING PARAMETERS >
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IM 12E04B40-02EN 1st Edition : Mar. 08, 2023-00
(6) During the hold, Air noise detection value is not checked. However, if a value greater than
“Air noise detection value” is continued for 5 seconds, the process moves to the same
process as “Denoising release time” in (7) without waiting for the Air denoising hold time.
(7) When the hold period is completed, the “Denoising release time” is checked unconditionally
and the turbidity is Denoising release time without checking the “output and displayed”.
(8) After the Denoising release time has elapsed, performs the Air noise detection value check
again.
[Notes on air denoising function]
The air denoising function is effective in processes where turbidity changes are relatively small
under normal conditions, but it may not be suitable for processes where sudden changes
often occur. Even if sudden changes do not usually occur, this function may be activated and
may cause a delay in the response of the reading or output if stepwise turbidity changes occur
occasionally.
Therefore, before using this function carefully consider the process conditions, and in order to
use it properly, determine optimum setpoints for the operating conditions while changing them
little by little. When using the function, pay attention to the following.
(1) Adjust the Air noise detection value according to the degree of reading change due to air
bubbles or dust.
(2) If an excessively long Air denoising hold time is set, the turbidimeter may not be able to detect
a change in reading that may have occurred and should have been recognized as real change.
(3) If the turbidity reading responses slowly due to the operation of this function, try turning
setup the “Bubble suppression release time” longer without changing the “Bubble
suppression hold time”.
(4) When an abnormal turbidity reading is suspected, turn off the function once and wait for
a while and see. The function may have prevented the turbidimeter from giving readings
properly.
Time
Turbidity
Air denoising hold time
Denoising release
time
In Process
A > Air noise detection value
A: Difference between the current signal and the previous signal
A < Air noise detection value
Turbidity Signal
Intake Cycle
Function restarts
Air Bubbles Detected
(No turbidity signal is taken
during the process)
A:Difference between the current signal and the previous signal
Figure 4.1 Air bubble suppression function