Tokyo Keiki UFL-30, Installation & Operation Manual

Page: 76 / 166

II-17
Calibration
[Correction of measurement values]
1. Zero shift (Zero point correction)
Addition and subtraction to compensate for offsets in measurement values can be performed.
Corrective value is a maximum, 7-digit alphanumeric including decimal point.
Displayed digits and decimal point position is determined by the input expression of the
forward max. flow value which is set by the analog output setting screen similar to the upper
and lower limit values. Value units are determined by the units of flow (units and exponent).
2. Span correction
Measurement values can be corrected by an exponential coefficient.
Correction value (coefficient) can be set in the range 0.100 to 2.000 relative to each flow
direction.
[Low Cut (flow volume cutoff)]
When the measured flow value is less than the flow value setting, ‘0’ flow can be imposed. The
cutoff value is expressed with an alphanumeric of 7-digit max. length including the decimal point.
Displayed digits and decimal point position are determined by the input expression of the forward
max. flow value which is set by the analog output setting screen similar to the upper and lower limit
values. Value units is determined by the units of flow (units and exponent).
[Smoothing]
Flow is expressed at the time it takes to achieve 90% of measuring flow rate during stepped
changes.
When flow measurement values fall into disarray, dampening can be enhanced by prolonging the
smoothing time. Specifically, the response to flow changes is dulled.
Fixed units are in sec., and the setting range is 0 to 120 seconds.
[ AGC (automatic gain control)]
You can select whether to automatically correct for variances in received signal level. When
automatic correction is selected, ‘AGC’ is displayed under ‘Status 1’ of the measurement screen.
Note:
This function is not normally used for reason that stable monitoring of received signal level cannot
be achieved under certain conditions such as when bubbles are generated. Caution should be
exercised as bubble formation often takes place when flow control valves are located close
upstream.