15
Chapter 2 Basic operation
2.1 Operation
overview
2.1.1 Turning the PhD Ultra on
The large black push-button on the top of the PhD
Ultra case is called the "MODE" button. It is used to
turn the PhD Ultra on and off, and to control most
other operations of the instrument. Push the mode
button once to turn the PhD Ultra on.
2.1.2 Start-up
sequence
After the detector has been turned on, it will
automatically go through an electronic self test and
start up sequence that will take approximately thirty
seconds. During the self-test sequence, the display
backlight will momentarily turn on, the visual LED
alarm lights will flash, and the audible alarm will
sound. The PhD Ultra will also determine which
“Smart Sensors” are currently installed, and whether
there have been any changes since the last time the
instrument was used.
The first screen shown during the start-up sequence
gives the instrument’s software version number.
The instrument will proceed to load instrument and
sensor data.
A screen will be shown for each sensor that is
recognized in the instrument.
etc.
The instrument serial number will be shown followed
by the datalogger interval screen.
The figure at the left represents the sampling
interval in minutes. The figure at the right
represents the operating time before the oldest data
will be overwritten by new data.
For more information on the datalogger
sampling interval settings, see section 4.5.3.
The instrument’s current date and time settings will
then be shown.
Note: If the date and time are incorrect, see
section 4.5.3.3 for instructions.
The PhD Ultra automatically evaluates itself to
determine its electronic fitness for use by
performing an electronic self-test.
During the self-test the audible alarm will sound and
each LED alarm light will be briefly activated. The
system’s onboard memory (RAM) will then be
tested.
The next screen shows the type of battery pack
installed, the current battery pack voltage, and
temperature in both Centigrade and Fahrenheit.
The temperature displayed is not necessarily the
temperature of the ambient air that surrounds the
instrument. The temperature shown is actually a
reading taken on the inside of the instrument case in
the area where the sensors are located. This
information is used by the PhD Ultra microprocessor
to properly adjust the sensor output when the
instrument is used in changing temperatures.
The current alarm settings will be shown before the
instrument is ready for use.
Note: PhD Ultra gas reading alarms are user
adjustable and may be set anywhere within the
range of the sensor channel. In many cases it is
possible to comply with OSHA guidelines while
using higher alarm points than the “default”
factory alarm settings. Factory default settings
may be easily restored at any time. The
procedure for changing or restoring the default
alarm settings is discussed in Chapter 4.
The final screen in the self-test and start-up
sequence is the current gas level screen. This
screen shows the kind of sensors currently installed
and the current readings. When the instrument is
operated in either the “Basic” or “Technician” mode,
numerical readings are shown.
