HT instruments HT4000 - Manual (Page 10)

HT4000
EN - 9
4.6. MEASUREMENT OF AIR FLOW
CAUTION
Do not touch the fans in the upper side of the external sensor to
avoid any damage.
1. Connect the external probe with the upper side of the instrument through the
corresponding terminal (see Fig. 1 – part 1)
2. Turn on the instrument pressing the key
3. Set the desired measuring unit relative to measurement of air speed (see § 4.4.2)
4. Press and hold the key
/ SET to enter the setting mode
5. Use the arrow keys
S or T and scroll “ArEA”
6. Press the key / UNIT to enter the setting pipe area
7. Use the keys ESC / REC and / UNIT to select flashing digits on display and the
arrow keys
S or T to increase or decrease the value of pipe area. The
maximum/minimum value to be set is 1.5m
2
/ 0.096m
2
or 16.15ft
2
/ 1.03ft
2
8. Press the key / UNIT to confirm the area value.
9. Select the measuring unit CMM or CFM on secondary display (see § 4.4.2)
10. Place the external probe parallel to air flow in the direction indicated by the arrow on its
top (see Fig. 3)
11. The value of air speed is shown on the instrument’s main display
12. The value of air flow is shown on the instrument’s secondary display.
13. Press the key HOLD / RECALL to hold the reading on display
14. For the use of the functions MAX, MIN and AVG see § 4.3.4
4.7. MEASUREMENT OF ATMOSPHERIC PRESSURE
The instrument carries out the measurement of atmospheric pressure by means of the
internal sensor placed on its top (see Fig. 1 – part 2)
1. Turn on the instrument pressing the key
2. Set the measuring unit of atmospheric pressure on secondary display (see § 4.4.2)
scrolling among hPa (ettoPascal = mbar), mmHg or inHg
3. The pressure value is shown on secondary display.