6F8A0917
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8.5.2 Zero
Offset
Adjustment
This function is used to perform zero adjustment simply by comparing the output of the flowmeter
with other process value without stopping the process flow.
If zero adjustment can be performed with still water condition, it is not necessary to set this adjustment
value.
How to calculate the zero offset value
Zero offset is performed by setting the adjustment value.
The adjustment value can be obtained by the following equation:
Adjustment value (%) = {(Actual flow rate)
−
(LF232 measured value)}
* Calculate the value in percent of the setting range of Range 1.
(See the example below.)
(Example)
Flow rate
Value in percent of the set span
Actual flow rate obtained from
other process value
10.0 m
3
/min
50.0 %
LF232 measured value
10.5 m
3
/min
52.5 %
Zero offset adjustment value
−
2.5 %
(If zero offset adjustment value is set to
−
2.5 %, the output of LF232 is shifted by
−
2.5% and 50.0 % output can be obtained.)
The zero offset adjustment value can be set within the range of
±
0.410ft/s (0.125 m/s) (
±
1.25% of
the maximum range 32.8ft/s (10 m/s))
Note: If you perform still water zero adjustment, zero offset adjustment value becomes zero.
Checking the zero offset adjustment value
Proceed as follows to check the zero offset adjustment value.
Switch operation
Display example
Description
O1: MANUAL ZERO
+002.5 %
Select O1: MANUAL ZERO from the setting item selection
menu.
The currently set zero offset adjustment value appears.
O1: MANUAL ZERO
Returns to the menu of setting item selection.
