RKI Instruments Gas Tracer - Manual (Page 76)

68 • Calibration Mode Gas Tracer Operator’s Manual
%volume calibration gas value screen in step 12 and using a
%volume methane cylinder.
If you are finished calibrating, use the (SHIFT)▼ button to navigate
to the NORMAL menu item, then press and release the POWER
ENTER button to return to Measuring Mode.
Calibrating with the Single Calibration Method
This section describes calibration using the Single Calibration method.
To calibrate using the Auto Calibration method, see “Calibrating with
the Auto Calibration Method” on page 65.
The procedure below describes a span adjustment of one channel
using a calibration kit that includes a 3-gas calibration cylinder, a 0.5
LPM (liters per minute) regulator, and non-absorbent sample tubing.
The standard 3-gas cylinder consists of 50% LEL methane, 12%
oxygen, 50 ppm CO, and a balance of nitrogen. In the example below,
the CH
4
channel’s span is adjusted. See “Parts List” on page 190 for
available calibration kits and calibration kit spare parts.
Calibration cylinders that contain only one target gas may also be
used for single calibration. For channels other than oxygen, RKI
Instruments, Inc. recommends that you use a cylinder that contains a
concentration of 10-50% of the full scale value of the target gas. For
example, if you are calibrating the combustible gas channel, your
calibration cylinder should have a combustible gas concentration
between 10% LEL and 50% LEL. For the oxygen channel, RKI
Instruments, Inc. recommends using 100% nitrogen to perform the
adjustment but any concentration between 0% oxygen (100%
nitrogen) and 17% oxygen can be used to make the adjustment.
NOTE: If your combustible gas channel is calibrated to a gas other
than methane, use an appropriate gas cylinder to perform the
calibration.
CAUTION: The single calibration method does not have a “FAIL”
notification. If a sensor cannot be set to agree with the
calibration source, see “Troubleshooting” on page 175.