RKI Instruments SDM-2012 PC Controlled Configuration - Manual (Page 100)

95 • Calibrating a Gas Tracer
Calibrating a Gas Tracer
The following instructions apply to standard Gas Tracers that contain the standard
sensors (catalytic LEL, ppm combustible, O
2
, and CO). They also apply to Gas
Tracers that have a %volume combustible gas sensor installed. See “Calibrating a
GX-2012” on page 65 for instructions to calibrate a GX-2012.
The PC Controller Program is capable of performing a calibration both manually and
automatically on a Gas Tracer. When a calibration is performed, the PC Controller
Program performs an air adjust operation on a Gas Tracer and then applies
calibration gas to the Gas Tracer. The PC Controller Program analyzes the calibration
results and determines if the Gas Tracer 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:
NOTE: Do not use a 4-gas cylinder or any cylinder that includes H
2
S when
calibrating a Gas Tracer. H
2
S adversely affects the ppm combustible
sensor.
1. Establish a connection between the SDM-2012, Gas Tracer, 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 the SDM-2012 or that a
humidifier manifold has been assembled for the GAS 2 fittings (see
“Assembling a Manifold for Multiple SDM-2012 Units” on page 15). 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.
4. Ensure that the gas out to instrument line is connected to the inlet of the Gas
Tracer and that the exhaust line is connected to the exhaust fitting of the Gas
Tracer.