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chosen in the calibration gas setting option, the
instrument will display H
2
S+ and hydrogen
sulfide must be used to verify accuracy. Use of
the incorrect calibration gas may lead to
inaccurate and potentially dangerous readings.
If the instrument recognizes a “CO Plus” sensor, the
display will show the “CO Plus Calibration Gas”
screen.
Use the “+” button to change the calibration gas
setting for the “CO Plus” sensor.
Once the appropriate calibration gas selected, press
the “CAL” button to advance to the next screen
showing the concentration of the gas chosen to
calibrate the “CO Plus” sensor.
Use the “+” and “-” buttons to change the
concentration of the gas that will be used.
4.3.11 Temperature Compensation
The PhD Ultra includes built-in temperature
compensation curves that allow the instrument to
give more accurate readings across a broad range
of operating temperatures. Temperature
compensation may be enabled or disabled by the
user as needed.
Note: The default setting for temperature
compensation is enabled. Biosystems
discourages disabling the PhD Ultra’s
temperature compensation.
(1) Move to the “Instrument Setup” screen as
described in section 4.3.1 and use the ‘CAL’ key
to scroll through the setup options until you
reach the “O2 Temp Comp” screen.
(2) Use the “+” and “-” buttons to change the
setting.
4.3.12 Saving changes and exiting the
Instrument Setup mode
When the PhD Ultra is properly configured, press
and hold the “CAL” button to save the changes. The
PhD Ultra will instruct you to release the button after
about 3 seconds.
A screen will briefly announce that changes have
been made and the instrument setup has been
updated.
The PhD Ultra will then turn itself off.
Pressing mode button to cancel the changes and
save the previous configuration.
4.4
Re-initializing the PhD Ultra
During production, all PhD Ultra detectors are
initially setup or programmed with the same
standard or “default” configuration (unless the
purchaser requests otherwise). The default
configuration may be restored at any time by using
the following procedure.
CAUTION:
Re-initialization will clear the
datalogger memory and cause the instrument to
revert to the default configuration. Verify that
any information needed from the datalogger has
been extracted prior to re-initializing the
instrument. If custom alarm and setup choices
are in use, remember to reset the alarm settings
and optional setup choices immediately
following the re-initialization.
Following initialization, the
PhD Ultra must be calibrated before being put
back into service. Failure to calibrate the
instrument following re-initialization may result
in inaccurate and potentially dangerous
readings.
To re-initialize the PhD Ultra:
(1) Make sure the instrument is turned off.
(2) Slide the belt clip towards the rear of the
instrument exposing the four buttons on the
instrument keypad.
(3) With the instrument turned off, simultaneously
press and hold down the "+" and “-” buttons.
(4) While holding down the "+" and “-” buttons,
press the mode button to turn the PhD Ultra
back on.
Do not release the “+” and “-” buttons until
the “Instrument Setup” message appears on
the display screen.
The display will then show the release date of
the software currently installed and the user-
assigned instrument ID number.
