General Calibration Notes; Zero Calibrations; Bump Test; Span Calibration - Honeywell VA201T Calibration Handbook

General Calibration Notes

When calibrating a detector...
ALWAYS refer to the product manual first!
YOU MUST use the proper Calibration Cap when calibrating
NEVER use the Weather Protection Housing or other accessories for calibration – use for Bump Test only
YOU MUST use the proper flow rate for the sensor type used in the transmitter

Zero Calibrations

Zero calibration is a recommended procedure that should be performed periodically to improve the performance
of the sensor. This is particularly important when the sensor is operating outside of normal environmental
conditions.
ALWAYS use Zero Air calibration gas or reference device (such as a calibrated portable) when doing
Zero Calibrations

Bump Test

A bump test is not intended to be an accurate calibration, but is used as a confidence check to ensure that
the gas detection system is functional. Some of the target gases are difficult to handle therefore bump testing
often makes use of cross sensitivities so that more convenient gases can be utilized.
The bump test is a functional check only.
Consult your local guidelines and/or product manual for recommended best practices

Span Calibration

Bump test versus calibration
Factory calibration is performed in a controlled environment with certified reference devices providing a high
level of accuracy. Field span calibrations are subject to external influences such as background concentrations
of gas and airborne contaminants that may affect the accuracy of a field calibration.
ALWAYS use the target gas for calibrations when possible otherwise contact the manufacture for approve
Cross-Calibration gas and predicted response to concentration (some gases can damage sensors)
Most products are calibrated to 50% FSD (Full Scale) while others may require other values – refer to
product manuals or contact the manufacture for details.

4-20mA Output Adjustment

It may be required to adjust the 4-20 mA output based on the installation. See the respective product
manual for specifics.
Calibration Handbook
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