Terminology Used With Zero Verification And Zero Calibration - Emerson Micro Motion LNG Series Configuration And Use Manual

Postrequisites
Restore normal flow through the sensor by opening the valves.
2.6.2 Terminology used with zero verification and zero
calibration
Table 2-1:

Terminology used with zero verification and zero calibration

Term
Zero
Factory Zero
Field Zero
Prior Zero
Manual Zero
Live Zero
Zero Stability
Zero Calibration
Zero Time
Field Verification Zero
Zero Verification
Configuration and Use Manual
Definition
In general, the offset required to synchronize the left pickoff and the right pickoff under
conditions of zero flow. Unit = microseconds.
The zero value obtained at the factory, under laboratory conditions.
The zero value obtained by performing a zero calibration outside the factory.
The zero value stored in the transmitter at the time a field zero calibration is begun. May
be the factory zero or a previous field zero.
The zero value stored in the transmitter, typically obtained from a zero calibration proce-
dure. It may also be configured manually. Also called "mechanical zero" or "stored zero."
The real-time bidirectional mass flow rate with no flow damping or mass flow cutoff ap-
plied. An adaptive damping value is applied only when the mass flow rate changes dra-
matically over a very short interval. Unit = configured mass flow measurement unit.
A laboratory-derived value used to calculate the expected accuracy for a sensor. Under
laboratory conditions at zero flow, the average flow rate is expected to fall within the
range defined by the Zero Stability value (0 ± Zero Stability). Each sensor size and model
has a unique Zero Stability value. Statistically, 95% of all data points should fall within the
range defined by the Zero Stability value.
The procedure used to determine the zero value.
The time period over which the Zero Calibration procedure is performed. Unit = seconds.
A 3-minute running average of the Live Zero value, calculated by the transmitter. Unit =
configured mass flow measurement unit.
A procedure used to evaluate the stored zero and determine whether or not a field zero
can improve measurement accuracy.
Quick start
11