Velocity Measurement; Volume Flow Funnel (Testo 445) - TESTO 445 Instruction Manual

A volume flow funnel is needed to measure the volume flow in a
ventilation opening (grid or outlet with dual wall clearance). The
opening of the funnel must be covered completely by the grid
(max. 190 x 190 mm with 0554.0400 or max. 350 x 350 mm with
0554.0410).
For the measurement, a velocity probe (0635.1041, 0628.0005
or 0635. 9540) is placed in the funnel's hole, is positioned in the
middle and is aligned. The probe is snapped into the funnel's
handle. Connect the probe to the instrument and switch on.
Position the cursor on the m/s parameter (
You will get to the "Parameter setting" menu by pressing
Press to get the volume flow (m
the m /h ON setting by pressing
3
Press twice and confirm with
(funnel/=funnel factor).
Enter the factor for the funnel used by you:
Funnel factor for funnel with part no. 0554.0400 = 20
Funnel factor for funnel with part no. 0554.0410 = 22
Press the funnel tightly on the opening. You can accept the
displayed reading as it is or you can carry out a timed mean
calculation if the readings fluctuate.
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7. Velocity measurement

Volume flow funnel (testo 445)

or
/h) in the display. Confirm
3
.
.
).
.