Metria 7722 Manual De Usuario página 5

MIN, MAX, STEL and TWA
Under normal mode, press M
of M /AV displays MIN, MAX, STEL, TWA in sequence and returns to normal mode.
N X
In MIN and MAX modes, it shows the minimum and maximum readings of CO
DP or WB temp. and humidity on the lower LCD (Fig. 5).
Figure 5
In STEL and TWA modes, the upper LCD shows the weighted average of CO2 readings for the past 15 minutes
(STEL) and 8 hours (TWA). The lower LCD shows the current AIR, DP/WB temp. and humidity (Fig. 6).
Figure 6
NOTE:
1. If the meter is turned on for shorter than 15 minutes, the STEL value will be weighted average of readings
taken since power on. Same for TWA values that appear before 8 hours.
2. It takes at least 5 minutes to calculate STEL and TWA. The LCD shows "----" (Fig. 7) during the first 5 minutes
from power on.
Figure 7
Alarm
The meter features visible and audible alarm to give warnings when CO
Users can set up 2 limits:
Upper limit: the alarm threshold requires air conditioning
1.
Lower limit: to stop the alarm.
2.
(See section P1.0 to set the alarm limits).
It emits beeps (Abt.80dB) with blinking LED when CO
pressing any key or automatically stop when CO
If the beeper is temporarily shut, it will sound again when readings fall below the lower limit and then go over
the upper limit again, or users press RESET key for more than 1 second to activate it.
LED alarm keeps blinking when beeps are manually shut. It stops only when readings fall below the lower limit.
N X /AVG to see the minimum, maximum and weighted average readings. Each press
reading falls below the lower limit.
2
concentration exceeds the limit.
2
level goes over the upper limit. Beeps can be stopped by
2
5
on the upper LCD and of AIR or
2