A Velocity
Sensing Port
B Scale
C Air Flow
Direction
Indicator
D Probe Collar
E Connecting
Leg
4
The Range Selector with the black lettering has the following ranges:
Velocity:
Static Pressure:
The Range Selector with red lettering has the following ranges:
Velocity:
Static Pressure:
A take-up adjustment screw (F) is provided for tightening the switch plate
(B) which may work loose through normal wear. A noticeable effort to
change the setting of the switch plate will indicate proper tightness.
Pitot Probe
The Pitot Probe is designed to measure the velocity of air in ducts and
also in unrestricted areas such as air intakes at grinding/buffing wheels
or ventilation slots at plating tanks. For the procedure to measure duct
velocities see pages 13 and 14; for other applications see page 10.
The air intake (and discharge) for the probe is at (A). The probe should
be held at right angles to the air flow; an arrow at the base of the probe
(C) should point in the direction of the air flow.
The probe is marked in one-inch increments (B) for convenience in
positioning the probe inside ducts.
The probe collar (D) acts as a stop when inserting the probe into the
Range Selector; an O-ring acts as a seal when the connecting leg (E) is
inserted into the Range Selector.
Low Flow Probe
The Low Flow Probe is designed for measuring velocities below 300 feet
per minute in open spaces; it attaches directly to the meter without
hoses.
An arrow (A) on the probe serves as a reminder of the direction you
must orient the probe and the meter when taking measurements.
Refer to page 10 for the proper velocity measuring procedure.
A Air Flow Direction Indicator
0 to 1250 fpm (0–6 m/s)
0 to 2500 fpm (0–12 m/s)
0 to 1 in H
O (0–20 mm H
2
0 to 5000 fpm (0–22.5 m/s)
0 to 10,000 fpm (0–45 m/s)
0 to 10 in H
O (0–200 mm H
2
O)
2
O)
2