11
Chapter 2. Basic operation
2.1
Overview of Ex Chek
operation
The Ex Chek offers a choice of two modes
of operation, "Text Only," and "Technician".
Mode selection should be based on how
much information is required, the skill level
of the user, and the nature of the job.
2.1.1 Operational warnings and
cautions
1.
The Ex Chek
personal, portable gas detector has
been designed for the detection of
combustible gas accumulations. An
alarm condition indicates the
presence of a potentially life-
threatening hazard and should be
taken very seriously.
2.
In the event of an
alarm condition it is important to
follow established procedures. The
safest course of action is to
immediately leave the affected area,
and to return only after further testing
determines that the area is once again
safe for entry. Failure to immediately
leave the area may result in serious
injury or death.
3.
Use only (DEMKO
approved) Duracell MN2400 or
Eveready E92, size AAA, 1.5V Alkaline
Batteries. Substitution of batteries
may impair intrinsic safety.
4.
The accuracy of Ex
Chek instruments should be checked
periodically with known concentration
calibration gas. Failure to check
accuracy can lead to inaccurate and
potentially dangerous readings.
5.
A sensor that
cannot be calibrated or is found to be
out of tolerance must be replaced
immediately. An instrument that fails
calibration may not be used until
testing with known concentration test
gas determines that accuracy has
been restored, and the instrument is
once again fit for use
.
6.
Do not reset the
calibration gas concentration
setpoints in the Ex Chek unless the
concentrations of your calibration gas
differ from the concentrations of the
calibration gas that is normally
supplied by Biosystems for use in
calibrating the Ex Chek.
7.
Use of non-
standard calibration gas and/or
calibration kit components when
calibrating the Ex Chek can lead to
dangerously inaccurate readings and
may void the standard Biosystems
warranty.
Biosystems offers calibration kits and
long-lasting cylinders of test gas
specifically developed for easy
calibration. Customers are strongly
urged to use only Biosystems
calibration materials when calibrating
the Ex Chek.
8.
Substitution of
components may impair intrinsic
safety.
9.
For safety reasons
the Ex Chek must be operated by
qualified personnel only. Read,
understand and follow the directions
set forth in this reference manual
before operating the Ex Chek.
10.
The Ex Chek has
been tested for intrinsic safety in
Explosive Gas/AIR(21.0% O
2
) Only.
