Zero Calibration - Omega FMA 4000 User Manual

The available K Factor settings are:
• Disabled
• Internal Index The index [0-35] from internal K factor table
• User Defined
Note: The conversion factors will not be applied for % F.S.
engineering unit.

5.3.7 Zero Calibration

The FMA 4000 includes an auto zero function that, when activated, automatical-
ly adjusts the mass flow sensor to read zero. The initial zero adjustment for your
FMA 4000 was performed at the factory. It is not required to perform zero calibra-
tion unless the device has zero reading offset with no flow conditions.
Note: Before performing Zero Calibration, make sure the device is
powered up for at least 15 minutes and absolutely no flow condition is
established.
Shut off the flow of gas into the Digital Mass Flow Meter. To ensure that no seep-
age or leak occurs into the meter, it is good practice to temporarily disconnect the
gas source. The Auto Zero may be initiated via digital communication interface or
locally by pressing the maintenance push button, which is located on the right side
of the flow meter inside the maintenance window above the 15 pin D-connector
(see Figure c-1 "FMA 4000 configuration jumpers").
Note: The same maintenance push button is used for Auto Zero
initiation and Totalizer reset. The internal diagnostic algorithm will
prevent initiating Auto Zero function via the maintenance push button
before the 6 minutes sensor warm up period has elapsed.
To start Auto Zero locally, press the maintenance push button. The status LED will
flash not periodically with the RED light. On the FMA 4000 with optional LCD, the
following screen will appear:
(K = 1).
(see APPENDIX II).
User defined conversion factor.
15