Vega FiberFlex LFXG-H, Operating Instructions Manual

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Calibration
44 LFXG-H Installation and Operation Guide
You can check the current loop output calibration at any time by using the
test mode to output a user-specified milliamp setting. See 68.
Calibration methods
For each installation, you must choose a method to calibrate the gauge. In
almost all cases, the standard method is the best.
Theory of calibration
Both calibration methods
Enter the values that define the maximum and minimum levels to measure.
These parameters are Max Level and Min Level, and must be set correctly
before any of the calibration steps.
Collection of data points nearest the maximum (but not higher) and
minimum (but not lower) levels occurs during calibration. See the procedure
on 50 to collect these data points.
Table 3.1
Calibration methods
Standard method Simple method
Use if the gauge is required to be
repeatable and precisely or linearly
indicate the level of process
throughout the span. Use if the gauge is only required to
be repeatable, but need not precisely
indicate the level of process.
Use for vessels in which it is critical
to know the precise level. Typically used for surge bins or other
vessels under control that maintains
one level.
The linearizer type chosen must be
Non-linear table. The linearizer type chosen must be
Linear table.
Note: The simple method produces a measurement indication that is
repeatable but not precise between the Cal Low Level and Cal
High Level points. The measurement indication is not linear
with respect to the actual process level.
In some applications, precision is not critical and this method is
valid.