18
10.
ALARM LEVEL SELECTION
To review or change alarm limits, remove the pan head #4-40 black screw (see Figure 3)
from the right side of the instrument (as you face it) using a Phillips screwdriver and access a
push-button switch with a short rod 3/32" (or less) in diameter. Set the front panel selector
switch to AUTO ZERO and after
"Air"
is displayed, press the push-button switch. The pump
will stop running and the instrument will enter a display/set-up mode for alarms and other
options.
Figure 3. Side view of detector.
To Display Alarm Levels Without Changing Them.
Each time the push-button is
pressed, the display advances through the sequence shown in Table 1. The display shows
whether an alarm or other option is ON or OFF, and if ON, at what level.
To Turn Off or On Alarms or Select Options.
Alarm levels for gas and CO can be
adjusted within certain limits or turned OFF, the beeper for the TRACK GAS scale may be
turned OFF, the CO display may be put on an air-free basis, and the block limit for the pump may
be adjusted by using the push-button and the RESET switch on the front panel. The oxygen
alarm limits are always ON at the factory set levels.
To turn an alarm OFF or select an option, enter the alarm display mode as described
above (set selector switch to AUTO ZERO and press the push-button once), advance to the
relevant display by pressing the push-button an appropriate number of times, and then press the
RESET switch. Each time RESET is pressed, the display changes from OFF to ON (and the
reverse). If the change to be made is to turn off a particular alarm or operating mode, once OFF
appears on the display, press the push-button. The display will show a symbol followed by OFF
(see Table 1). Exit by turning the selector switch out of the AUTO ZERO position or continue,
by pressing the push-button, to a subsequent display of another alarm or option to be changed.
The oxygen alarms and the block level for the pump cannot be turned OFF. If OFF is entered
with RESET, when the push-button is pressed, the display will show
"LoO2"
or
"HiO2"
or "
Pu"
followed by a number (19.5 for LoO2, 23.0 for HiO2 and the block limit for the pump).
