197 • Calibrating GX-2012s and Gas Tracers
Calibrating GX-2012s and Gas Tracers
The following instructions apply to standard GX-2012s that contain the standard
sensors (catalytic LEL, O
2
, H
2
S, and CO) as well as standard Gas Tracers that
contain the standard sensors (catalytic LEL, ppm combustible, O
2
, and CO). They
also apply to GX-2012s and Gas Tracers that have a %volume combustible gas
sensor installed. See “Calibrating a GX-2012” on page 65 or “Calibrating a Gas
Tracer” on page 95 for instructions to calibrate a GX-2012 or Gas Tracer,
respectively.
The PC Controller Program is capable of performing a calibration both manually and
automatically on an instrument. When a calibration is performed, the PC Controller
Program performs an air adjust operation on an instrument and then applies
calibration gas to the instrument. The PC Controller Program analyzes the calibration
results and determines if the instrument passed the calibration.
NOTE:
The PC Controller program performs a complete calibration on the
ppm combustible sensor first. Be sure that the 1000 ppm methane
calibration cylinder is connected to the GAS 2 fitting on the back of the
SDM-2012 using a 6 inch humidifier tube.
To manually calibrate an instrument or instruments:
1.
Establish a connection between the SDM-2012, the instrument, and the PC
Controller program as described in “Connecting Instruments to the PC
Controller Program” on page 43.
2.
Verify that all of the calibration parameters are set correctly. See “Setting Up
the Configuration” on page 32 for instructions.
3.
Verify that the appropriate calibration gas cylinder(s) are connected to the
appropriate SDM-2012(s) or manifold line(s). The ppm sensor will be bump
tested first. Be sure that a 6 inch humidifier tube is used to connect the ppm
calibration cylinder to the GAS 2 fitting on the back of any SDM-2012(s) with
Gas Tracers installed. If you have assembled a humidifier manifold for the
GAS 2 fittings of the SDM-2012s with Gas Tracers installed (see “Assembling
a Manifold for Multiple SDM-2012 Units” on page 15), be sure the ppm
calibration cylinder is connected to the inlet of the manifold. If you are using a
zero air cylinder for the fresh air adjustment, install a 6 inch humidifier tube
between the regulator and the AIR fitting on the back of the SDM-2012.
NOTE:
Do not use a 4-gas cylinder or any cylinder that includes H
2
S when
bump testing or calibrating a Gas Tracer. H
2
S adversely affects the
ppm combustible sensor. If you have assembled a manifold, be sure
that one manifold exists for the SDM-2012s with GX-2012s installed
and that a separate manifold exists for the SDM-2012s with Gas
Tracers installed.
