General Tools and Instruments CDM7722 - Manual (Page 6)

In STEL and TWA modes, the main
display shows the
(STEL) and 8 hours(TWA).
weighted average of
CO readings for the past 15 minutes
2
The lower
displays are the current AIR, DP/WB
temperatures and humidity (7722/
77232). (Fig.6)
5
% %
O O
STEL
CO
2
Fig.6
PPM
NOTE:
1.
If the meter is turned on for shorter
than 15 minutes, the STEL value will
be the weighted average of readings
taken since power on. Same for TWA
values appear before 8 hours.
2.It takes at least 5 minutes to calculate
STEL and TWA. The display shows
“----” (Fig.7) during the first 5 minutes
from power on.
% %
O O
STEL CO 2
Fig.7
The meter features visible and audible
alarm to give warnings when CO con-
2
centration exceeds the limit. Users can
set up 2 limits: An upper limit for alarm
threshold that requires air conditioning
and a lower limit to stop the alarm.
(See P1.
0
in setup for setting alarm
limits).
ALARM & OUTPUT
ALARM