GasWatch 3 for CO and O
2
Chapter 5: User Mode and Calibration • 37
Tips for Using User Mode
•
To scroll from one item to the next, press and release AIR. To reverse the scrolling
direction:
a. Press and hold AIR.
b. Immediately press POWER/MODE and then release both buttons.
c. The scrolling direction returns to the original direction when you exit and reenter a
menu.
•
To skip an item when a question is asked, press and release AIR.
•
To enter an item and to save any changes, press and release POWER/MODE.
•
To change a flashing parameter, press and release AIR. To reverse the direction of change
(ie. from increasing to decreasing or vice versa):
a. Press and hold AIR.
b. Immediately press POWER/MODE and then release both buttons.
•
To exit an entered item without saving a change, press and hold AIR and POWER/MODE
for a few seconds.
Performing a Bump Test (BUMP)
Bump test the instrument before each day’s use with a known concentration of each target gas.
The instrument does not need to be calibrated unless it does not pass the bump test.
To bump test the GasWatch 3, you need:
•
Calibration gas cylinder (RKI Instruments recommends using 50 ppm CO in N
2
)
•
0.25 LPM fixed flow regulator
•
Non-absorbent tubing
•
Calibration cup
1. Confirm that the GasWatch 3’s calibration gas values match the concentrations listed on
the calibration gas cylinder as described on pg.54.
2. Confirm that the regulator knob is turned all the way clockwise. Screw the 0.25 LPM
fixed flow regulator onto the calibration cylinder.
3. Install the calibration cup onto the GasWatch 3. The calibration cup has an indicated flow
direction. Be sure the calibration cup is installed in the correct direction and that it is
pushed on all the way.
