10
Chapter 3
HUMIDITY
Key (Model 8386/8386A Only)
Press to toggle between displaying % relative humidity, dew point
temperature, and wet bulb temperature on the large digits. (The first time
that the button is pushed it will display the last measurement type that was
displayed.)
NOTE: To display accurate wet bulb temperature, the correct
barometric pressure must be entered. See
section for
details on setting the barometric pressure. NOTE: For temperature and
humidity measurements, make sure that at least 3 inches (7.5 cm) of the
probe is in the flow to allow the temperature and humidity sensors to be in
the air stream.
THERMAL/PITOT
Key (Models 8385/8385A/8386/8386A Only)
Press to toggle back and forth between measuring velocity or flow rate with
the thermal anemometer sensor or with a Pitot tube attached to the pressure
ports.
NOTE: If this key is pressed while displaying anything other than
velocity or flowrate, it will have no effect on the readings.
ACTUAL/STANDARD
Key
Press to toggle between displaying actual and standard velocity or flow rate.
Press and hold to view, enter, or change ambient conditions. When the key is
pressed and held, the pressure units will flash and the last barometric
pressure entered will be displayed. Use the
keys to change the
barometric pressure and press
ENTER
to accept it. Then the temperature units
will flash and the last temperature entered will be displayed. Use the
keys to change the temperature and press
ENTER
to accept it and return to
measuring mode. The ranges that can be entered are as follows: Pressure: 15
to 40 in. Hg (381 to 1016 mm Hg), 29.92 in. Hg (760 mm Hg) is default;
Temperature: -80 to 400°F (-62 to 204°C), 70°F (21.1°C) is default.
NOTE:
When obtaining wet bulb temperature or heat flow readings, the correct
barometric pressure must be entered. Both the barometric pressure and
temperature need to be entered when measuring the following: 1) actual
velocity (or flow rate) with either the thermal anemometer or the Pitot tube,
or 2) standard velocity (or flow rate) with a Pitot tube.
SAMPLE INTERVAL
Key
The
SAMPLE INTERVAL
key is used to set the time constant and logging
intervals. Press to display current time constant. Use
to scroll through
the time constant choices, which are 1 s, 2 s, 5 s, 10 s, 15 s, 20 s, and LOG
symbol, then press ENTER to accept the choice. If LOG was chosen, the
first logging interval choice will be displayed. Use
to scroll through the
logging interval choices, which are 2 s, 5 s, 10 s, 15 s, 20 s, 30 s, 1 min, 2
min, 5 min, 10 min, 15 min, 20 min, 30 min, 60 min, and OFF. Press
ENTER to accept choice and return to measuring mode
.
If a logging interval
is chosen that is shorter than the time constant, the time constant will be
shortened to be equal to the logging interval.
