CO250 V1.2 1/09

5

MIN,MAX,STEL,TWA

In the normal mode, press the Max/AV button to see the minimum, maximum, and

weighted average readings. With each press of the Max/AV button, the meter displays

MIN, MAX, STEL, TWA in sequence and then returns to the normal mode.

(main display), AIR, DP or WB temperatures (lower left display) and Humidity (lower right

display).

for the past 15 minutes (STEL) or 8 hours(TWA). The lower displays are the current

measurements

NOTE:

1.

If the meter has been powered on for less than 15 minutes, the STEL value will be

the weighted average of readings taken since power on. As well, the TWA mode

will display a weighted average of readings prior to 8 hours of operation.

2.

The CO250 takes at least 5 minutes to calculate STEL and TWA. The display

shows “----” during the first 5 minutes from power on.

3.

The STEL and TWA values will keep updating every 5 minutes.

ALARM

when any key (except

SET

) is pressed or the readings fall below the set value. It beeps

again if the value exceeds the limit. Restart the meter if the beeper will not stop.

AUTO POWER OFF

The meter turns off automatically after 20 minutes of inactivity. To override the function,

press and hold down the

SET

and HOLD buttons until “n” appears in the display (approx.

2 seconds) while turning on the meter on. NOTE: Auto sleep function will be disabled

during calibration mode.

%

O

STEL

%

O

STEL