Calibration Procedure; General; Equipment Required; Preparation - vectus ALNOR Balometer Jr. Manuel Du Propriétaire

14

CALIBRATION PROCEDURE

General

The Balometer Jr. is easily calibrated assuming that your calibration
facility has access to the proper equipment. Each range uses an easily set
single screw adjustment for calibration. However, the procedure should
be attempted only by persons who have the proper equipment. Note that
any attempt at recalibration voids all calibration certification provided
with instrument.

Equipment Required

Wind tunnel capable of providing controllable air flow in both supply
and exhaust directions from 50 to 1400 cfm (85 to 2400 cmh, 24 to
660 l/s); measurement standard for air volume in the same range;
measurement standard for air volume between 50 and 1400 cfm (85 to
2400 cmh, 24 to 660 l/s); 2' x 2' outlet air diffuser similar to ones
typically in use; / " hex adjustment device at least 2
1
16
device is useful).
The wind tunnel and measurement standard should be controllable and
accurate to within five times the accuracy of the scale being calibrated.

Preparation

1. Verify that there are no cracks in the manifold or leaks in the hoses
connecting the manifold to the range selector.
2. Connect wind tunnel, measurement standard, diffuser and Balometer
Jr. in such a way that the air which passes through the Balometer Jr.
has also passed through the measurement standard and diffuser.
Make sure there are no leaks in the system as any leaks will cause
errors in calibration.
3. Allow the Balometer Jr. and tunnel to stabilize at an air temperature
between 68°F and 86°F (20–30°C) before attempting to calibrate the
instrument.

Calibration

1. Set up Balometer Jr. with 2' x 2' hood.
2. Set up Balometer Jr. on wind tunnel so that air volume through unit
can be determined from measurement standard.
3. Turn off all air through Balometer Jr. and set range selector to OFF
position.
4. Using zero adjust screw, set Velometer Jr. meter to 0.
5. Turn on wind tunnel and set to 180 cfm (300 cmh, or 90 l/s).
" long (―ball end‖
/
1
2