Fluke 923 User manual

PN 4024518
September 2011
© 2011 Fluke Corporation. All rights reserved. Printed in Taiwan.
Specifications are subject to change without notice.
All product names are trademarks of their respective companies.
923
Air Velocity Meter
Users Manual

LIMITED WARRANTY AND LIMITATION OF LIABILITY
This Fluke product will be free from defects in material and
workmanship for two years from the date of purchase. This
warranty does not cover fuses, disposable batteries, or
damage from accident, neglect, misuse, alteration,
contamination, or abnormal conditions of operation or
handling. Resellers are not authorized to extend any other
warranty on Fluke’s behalf. To obtain service during the
warranty period, contact your nearest Fluke authorized
service center to obtain return authorization information,
then send the product to that Service Center with a
description of the problem.
THIS WARRANTY IS YOUR ONLY REMEDY. NO OTHER
WARRANTIES, SUCH AS FITNESS FOR A PARTICULAR
PURPOSE, ARE EXPRESSED OR IMPLIED. FLUKE IS
NOT LIABLE FOR ANY SPECIAL, INDIRECT,
INCIDENTAL OR CONSEQUENTIAL DAMAGES OR
LOSSES, ARISING FROM ANY CAUSE OR THEORY.
Since some states or countries do not allow the exclusion
or limitation of an implied warranty or of incidental or
consequential damages, this limitation of liability may not
apply to you.
Fluke Corporation
P.O. Box 9090
Everett, WA 98206-9090
U.S.A.
Fluke Europe B.V.
P.O. Box 1186
5602 BD Eindhoven
The Netherlands
11/99

i
Table of Contents
Title Page
Introduction ................................................................ 1
Safety Information ...................................................... 2
Symbols ..................................................................... 2
Features..................................................................... 3
Product Use ............................................................... 3
The Display ............................................................. 6
Buttons .................................................................... 8
Auto Power Off ........................................................ 9
Velocity Probe ......................................................... 9
IR and RF Communication ...................................... 12
Air Velocity and Flow............................................... 12
Measure Velocity .................................................. 12
Measure Flow ....................................................... 13
Samples .................................................................. 14
Measurement Units ................................................. 14
Velocity Alarm ......................................................... 16
Clear All................................................................... 16
Recall ...................................................................... 17
Calculate Average ................................................... 17
Maintenance .............................................................. 17
Clean the Product.................................................... 18
Change the Batteries............................................... 18
How to Contact Fluke................................................. 21
Specifications............................................................. 22

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Users Manual
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Electrical Specifications .......................................... 22
Mechanical Specifications ...................................... 23
Environmental Specifications.................................. 23
Safety Compliance.................................................. 24
Miscellaneous Specifications.................................. 24

1
Introduction
The 923 Air Velocity Meter (the Product) is a handheld, indoor-air
quality diagnostic instrument. It uses a probe that can be used
while attached to the Product or in wireless mode away from the
Product base.
The Product measures, calculates, and displays:
•Air temperature measured in Celsius (°C) or Fahrenheit (°F).
•Air velocity (actual) measured in m/s or fpm.
•Flow rate displayed in l/s, cfm or m3/hr.
•Average indications for temperature, velocity, and flow.

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Users Manual
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Safety Information
XWWarnings
To prevent possible electrical shock, fire, or
personal injury:
•Use the Product only as specified, or the
protection supplied by the Product can be
compromised.
•Do not use the Product around explosive gas,
vapor, or in damp or wet environments.
Symbols
Symbols used in this manual and on the Product are shown in
Table 1.
Table 1. Symbols
Symbol Meaning
WRisk of danger. Important information. Refer to
manual.
PConforms to relevant European Union directives
~Do not dispose of this product as unsorted
municipal waste. Go to Fluke’s website for
recycling information.
MBattery
©Wireless mode is active.

Air Velocity Meter
Features
3
Features
The Product features:
•A wireless telescopic probe
•LED backlight
•Auto power off
•Low-battery indicator
•Velocity alarm
•US and Metric measurement options
•Single-point and continuous data log options
•Probe sensor cover
•Protective case
Product Use
The subsequent sections tell you how to use the Product. Figure 1
and Table 2 show the buttons, indicators, and sensors on the
Product.

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Users Manual
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SAVE
1
2
3
4
5
6
8
9
11
12
13
7
14
10
grx001.eps
Figure 1. The Product

Air Velocity Meter
Product Use
5
Table 2. The Product
Item Description Item Description
Display (LCD) Shift button
Power button Save button. Push Shift
to set air velocity alarm.
Backlight button IR Sensor
Velocity button. Push
Shift to set Units.
Save button
Flow button. Push Shift
to enter barometric
pressure.
Wireless indicator.
Flashes in wireless
mode.
Enter button. Push Shift
to recall saved records.
Telescopic probe
Calculate Average
button. Push Shift to
clear all saved samples.
Velocity sensor

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Users Manual
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The Display
Figure 2 and Table 3 show the display.
43 5
6
7
8
9
11
12
13
141516
17
18
19
21
22
20
10
1 2
grx002.eps
Figure 2. Display

Air Velocity Meter
Product Use
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Table 3. Display
Item Description Item Description
Flow indicator Millimeters of Mercury
indicator
Velocity indicator 
Low battery indicators
for the Probe and the
Product body
Clear All? indicator Velocity alarm indicator
Recall indicator Shift indicator
Samples indicator Fahrenheit and Celsius
indicators
Number of samples
indicator Wireless indicator
Meters per second
indicator Temperature display
Feet per minute indicator Primary display
Cubic feet per minute
indicator Duct diameter, X and Y
size indicators
Cubic meters per hour
indicator Duct-type indicators
Liters per second
indicator Up and down indicators

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Users Manual
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Buttons
Table 4 explains the Product buttons.
Table 4. Buttons
Button Function
Power- Push to turn the Product on or off.
Backlight- Push to turn the backlight on or off.
Units

Velocity- Push to see velocity and temperature.
When used with you can set measurement
units.
Clear All

Calculate Average- Push to see the average
value of recorded data. When used with 
you can delete all recorded data. Also used for
.
Set Barometric

Flow- Push to enter duct parameters and flow.
When used with and and you can
enter barometric pressure.
Set Alarm

Save- Push to record measurement data. Push
to set the velocity alarm. Also used for .

Air Velocity Meter
Product Use
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Table 4. Buttons (cont.)
Button Function
Recall

Enter- Push when you set the measurement or
function parameters to keep the value. When
used with and and , you can recall
recorded data.

Shift- The Products secondary functions operate
with . Secondary functions are shown
above the buttons.
Save- (Located on the Probe). Push to record a
current probe measurement.
Auto Power Off
To conserve battery power, the Product turns off after 15 minutes
of non-use. Push to turn the Product on.
Velocity Probe
The Velocity Probe measures air velocity and temperature. When
the Product is turned on, the wireless indicator light on the Probe
lights (©). If the indicator does not come on, make sure the
Probe battery is charged or replace it if necessary. When the Probe
is removed from the Product base, the wireless indicator light will
flash and ©shows on the display. To remove the Probe from the
base, see Figure 3.

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Users Manual
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grx006.eps
Figure 3. Detach the Probe
Use the Probe while it is attached to the Product base, as shown in
Figure 1 or use it in wireless mode away from the base, as shown
in Figure 4.

Air Velocity Meter
Product Use
11
grx005.eps
Figure 4. Velocity Probe Use

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Users Manual
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IR and RF Communication
When the Probe is connected the Product base, the two
communicate with infrared (IR) sensors. When the Probe is used
away from the base in wireless mode, the Probe uses radio
frequency (RF) to communicate with the base. If unable to
communicate in RF mode, turn the Product off, connect the Probe
to the base, and push to turn the Product on.
Air Velocity and Flow
The Product measures actual air velocity and volume flow rate to
find the overall velocity indication.
Measure Velocity
Note
To measure velocity, a barometric pressure reading is
necessary. The barometric pressure on the Product
defaults to sea level but can be adjusted. If you use the
default but are not at sea level, you will still get a velocity
reading, but there may be a slight error due to the
incorrect barometric pressure.
To measure velocity, first enter the barometric pressure:
1. Push and to access the Set Barometric function.
2. Push and to record the barometric pressure.
3. Push .

Air Velocity Meter
Product Use
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To measure velocity:
1. Push .
2. Put the probe sensor perpendicular (90 °) to the air stream
that you will measure. Make sure that the sensor cover is
pulled back to show the sensor.
3. Push on the Product base, or on the Probe to capture
the velocity reading.
Note
The Samples indicator on the display increases.
Measure Flow
To measure flow:
1. The type and dimensions of the air duct are necessary for the
measurement. To record this data:
a. Push .
b. Push and to select the air duct type: or .
c. Push .
d. Push and to record the duct measurements.
If the duct is circular:
1. Record the diameter (Dia).
2. Push .
If the duct is rectangular:
1. Record the width (X) and push .
2. Record the height (Y) and push .

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Users Manual
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2. Put the Probe sensor perpendicular to the air stream that you
will measure. Make sure that the sensor cover is pulled back
to show the sensor.
3. Push on the Product base, or on the Probe to record
the flow indication.
Note
The Samples indicator on the display increases.
Samples
The Product can record 99 samples of velocity and 99 samples of
flow measurement data, 198 samples total.
To see the recorded samples:
1. Push .
2. Push to access the Recall function.
3. Push to move forward and to move backward through
the samples.
All data for the recorded samples is shown.
Measurement Units
The Product shows measurements in different measurement units.
To choose which units are shown:
1. Push .
2. Push to access the Units function.

Air Velocity Meter
Product Use
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The first Flow units screen shows. To change the measurement
units for the duct size to centimetres (cm) or inches (in):
1. Push and to choose between cm and in.
2. Push to save the choice.
The second Flow units screen shows. To change between cubic
feet per minute (cfm), litres per second (l/s), and cubic meters per
hour (m3/hr):
1. Push and to choose the necessary measurement unit.
2. Push to record the selection.
The Velocity units screen shows. To change between feet per
minute (fpm) or meters per second (m/s):
1. Push and to choose the necessary measurement unit.
2. Push to record the choice.
The temperature units screen shows. To select between degrees
Fahrenheit (°F) and degrees Celsius (°C):
1. Push and to choose the necessary measurement unit.
2. Push to record the choice.
The Product changes to velocity mode. To exit from the
measurement units menu, push . All preferences to that point
are kept. The preferences are also kept if the Product turns off.

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Users Manual
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Velocity Alarm
The velocity alarm starts if the measurement is above the alarm
user preset. When the alarm goes off, the Product base vibrates
and beeps one time per second. The alarm can also be turned off.
To set the velocity alarm:
1. Push .
2. Push to access the Set Alarm function.
3. Push to turn the alarm on or off.
4. Push .
5. If the alarm is turned on, push and to increase or
decrease the alarm setting.
6. Once the correct setting shows, push .
ALARM shows on the display if the alarm is active when in velocity
mode. The alarm position is kept and stays active until the alarm is
stopped. If the Product is turned off the alarm adjustments are
kept.
Clear All
To clear all stored readings:
1. Push .
2. Push (Clear All). The Product asks “Clear All?”.
3. Push . Notice that the Samples indicator changes to 0.
The stored readings have been cleared.