Spectrex SafEye Xenon 700S, Руководство пользователя

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Principles of Operation
20 SafEye
TM
Xenon 700S Gas Detector User Guide
2.3.6 Gas and Mixture Selection and Setting
At the 3.4µ spectral band of the SafEye Xenon 700, the least sensitive gas is
pure (100% volume) methane and the most sensitive gases are various
mixtures of methane with heavier alkanes, where the methane percentage
is less than 90%. For pure ethane, the sensitivity is close to the high
sensitivity gases, and for pure propane, it lies somewhere between the 2
extremes. Every SafEye has 4 built-in gas calibration settings that can be
changed by function setup. The setting for each SafEye is detailed on the
calibration datasheet provided with each unit.
The calibration settings are designed for use in various applications. Models
701, 702, and 703 are calibrated to 4 different gases as follows:
Table 2: Gas Calibrations
Gas Type Description
Gas 1 Pure methane, and is for use in methane storage and piping
applications
Gas 2 92% methane, 4% propane and 4% ethane (default).
Universal oil and gas production mixture to be used in all
cases where methane concentration in the mixture does not
exceed 98%. It can also be used for pure ethane
applications.
Gas 3 LPG - 60% propane and 40% butane.
Gas 4 99% methane and 1% propane, and is for use in detecting a
methane mixture with heavier gases, where the methane
component can vary between 100% and 95%. It is also
good for protecting areas where a leak can be either pure
methane or pure propane.
Models 721, 722, and 723 are calibrated to 1 gas only Gas 1 – ethylene
100%.
The 4 internal gas calibrations cover most of the flammable gas detection
applications. Actual selections should be made by the user in consultation
with experts to provide for safety requirements. However, for special cases
where none of the 4 calibrations are appropriate, SPECTREX, through its
local agents, can advise how to calibrate a SafEye Detector to any specific
gas.
2.3.7 Flash Source
The Xenon Flash Source was originally introduced in the first SafEye
development and was designed to overcome false alarms, which were
experienced by early generations of the open path system. The new SafEye
Xenon 700S employs the latest generation of flash bulbs to provide even
more power and an extended operation life of up to 10 years.