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9.
Calibration Mode
This section describes how to perform a fresh air adjustment, an automatic span adjustment, and a manual
span adjustment on the SP-220. It also describes how to turn on the Calibration Mode password function.
This version of the SP-220 must be calibrated with both hydrogen (H2) and methane (CH4).
9-1. Fresh Air Adjustment
RKI Instruments, Inc. recommends that the fresh air adjustment be performed in a fresh air area (area
known to be free of toxic and combustible gases and of normal oxygen content, 20.9%). If a fresh air
environment is not available, a cylinder of zero air can be used as long as the gas is applied through a
humidifier tube. Calibration kits for the SP-220 do not normally include zero air or a humidifier tube.
1 Be sure the SP-220
has been running in
Detection Mode for
at least 10 minutes
before continuing.
2 With the instrument
running in Detection
Mode, press and hold
the AIR and MODE
buttons for 3
seconds.
3 If the Calibration
Mode password
parameter has been
set to on (factory
setting is off), you
will be prompted for
a password.
Use the AIR and
MODE buttons to
adjust each
character and press
the POWER button to
move to the next
character.
