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Quick Start
1. Connect AAT3 to Fieldpiece meter.
2. Select mVDC range on meter.
3. Remove vinyl slip cover from the
probe tip.
4. Select desired switch position on
AAT3 for temperature, %RH, or air
velocity.
5. Read your measurement directly on
the display of the Fieldpiece meter.
Certifications
C-Tick (N22675)
CE
WEEE
RoHS Compliant
Description
Yo u r A AT 3 i s a p o r t a b l e ,
psychrometer accessory head, with a
built in hot wire anemometer.
The compact probe tip makes
directly measuring in ducts a breeze.
The 38"(96cm) telescopic probe with
laser etched ruling and flattened
edges allows you to locate proper
measurement points within a duct and
ensures that your probe is properly
aligned for air velocity measurements.
The AAT3 can measure percent
relative humidity, dry bulb, and air
velocity and can calculate wet bulb
and dew point.
The AAT3 snaps directly onto the
Fieldpiece HS series DMMs. For other
meters, use Fieldpiece ADLS2 test
leads or AHDL1 handle adapter.
Use your AAT3 with the HVAC Guide
to easily calculate in-duct CFM or
to perform Target Evaporator Exit
Temperature tests and get accuraate
Target Superheat calculations.
Go wireless with your AAT3 by
using Fieldpiece wireless transmitters
(ET2W/EH2W) to send measurements
over-the-air to Fieldpiece wireless
receivers (HG3, LT17AW, EH4W )
anywhere on the jobsite.
Fieldpiece
In-Duct
Psychrometer
and Air Velocity
Head
Model AAT3
OPERATOR'S MANUAL
How to Use
General Instructions
1. Remove sensor cap from the telescoping
probe tip.
2. Connect directly onto any Fieldpiece
HS multimeter, data logget or the HG3 HVAC
guide. For most Fieldpiece SC and LT meters,
use Fieldpiece ADLS2 test leads plugged into
the COM and VΩ jacks.
3. Select mVDC range on multimeter.
4. Set switch position of AAT3 to °F and°C,
Ft/min and M/s, or %RH.
a.) For temperature set temp type switch
to DRY BULB, WET BULB or DEW POINT.
b.) For velocity measurements wait for 10
seconds as the AAT3 warms up.
5. Read the measurement directly on
the multimeter display.
What is Free Area?
How Do I Get It?
Free Area is the total area through
which air can flow on either a supply
outlet or a return grille. Free area
is also some times referred to as
"effective area" or "see through area."
If there is no grille or restriction on
the area through which air is flowing
then the free area is equal to the actual
area. This would be the case if you are
performing an in-duct measurement
or if you were to remove the grille
from a supply or return.
If you are measuring airflow where
there is an obstruction present then
the free area is the total area minus
area covered by the fins or grating.
Free Area is published by grille
manufacturers and is the most
accurate representation of the Free
Area of a duct. Use manufacturer's
data whenever available.
Specifications
Operating environment:
Air Velocity: -4°F to 140°F (-20°C to 60°C)
Temperature: -4°F to 140°F (-20°C to 60°C)
Relative humidity: 32°F to 131°F (0 to 55°C)
Storage temp:
-4°F to 140°F (-20°C to 60°C) <80%
R.H. (Batteries removed)
Output impedance:
approx. 1KΩ
Temperature coefficient:
0.1 x (specified accuracy)
per °C (<18°C or >28°C) (<64°F or >82°F)
AIR VELOCITY
Range:
40-3940 ft/min (0.20-20.00 m/s)
note: to use full range AAT3 must be connected to a
DMM with a 4000 mVDC range or greater.
Accuracy:
± (5%+1 dgt) reading or ± (1%+1dgt)
full scale.
RELATIVE HUMIDITY
Range:
0% to 100% RH
Accuracy:
±2.5% @ 73.4°F (23°C), 10% to 90% RH
±5% @ 73.4°F (23°C), <10% RH, >90% RH
Sensor Response Time:
60 seconds typical for 90%
of total range.
Sensor Hysteresis:
±1%RH typical
TEMPERATURE
Range:
-4°F to 140°F (-20°C to 60°C)
Accuracy:
±1°F
32°F to 113°F
±2°F
-4°F to 32°F, 113°F to 140°F
±0.5°C
0°C to 45°C
±1°C
-20°C to 0°C, 45°C to 60°C
Sensor type:
Air velocity:
Tiny glass bead thermistor.
Relative Humidity:
Capacitance polymer film.
Temperature:
Precision thermistor.
Battery:
9V
Battery life:
20 -35 hours typical
Battery indication:
Red Lo Batt LED
Auto Power off:
after 15 minutes of inactivity if APO
is active.
Dimensions:
144mm(H) x 67mm(W) x 32mm(D).
Weight: approx.
240g including battery.
Maintenance
Clean the exterior with a dry cloth.
Do not use liquid.
Battery Replacement
When Lo Batt LED lights up replace
old battery with new 9V battery.
Sensor Care
When not in use it is best to protect
this sensors with the vinyl slip cover
included with the AAT3.
Extreme conditions or exposure to
solvent vapors may offset the RH%
sensor. If this happens, place the
sensor in a controlled envrionment of
75%RH and between 68°F - 86°F for a
period of 24 hours.
To create a 75%RH environment
moisten a small amout of table salt,
in an open container such as a clean
2 liter bottle cap.
Place the container with the salt
solution and the AAT3 probe in a
sealable plastic bag, and leave the bag
in a room temperature location where
it will not be disturbed for 24 hours.
Note: It is important that the salt
solution does not come in direct
contact with the sensor, as this may
permenantly damage the sensor.
Optional accessories
RCONE1 and AAT3 working with
ET2W and HG3 to wirelessly log
Wetbulb for target superheat testing.
80
AAT3
In-Duct
Psychrometer
& Air Velocity
Head
ON
LO BATT
AVG
ENGLISH
ENGLISH METRIC
RH%
Ft/min
°F
RH%
M/s
°C
METRIC
DRY BULB
WET BULB
DEW POINT
AVG
NORMAL
A TO O
Limited Warranty
This meter is warranted against
defects in material or workmanship
for one year from date of purchase.
Fieldpiece will replace or repair the
defective unit, at its option, subject
to verification of the defect.
This warranty does not apply to
defects resulting from abuse, neglect,
accident, unauthorized repair,
alteration, or unreasonable use of
the instrument.
Any implied warranties arising
from the sale of a Fieldpiece product,
including but not limited to implied
warranties of merchantability and
fitness for a particular purpose, are
limited to the above. Fieldpiece shall
not be liable for loss of use of the
instrument or other incidental or
consequential damages, expenses, or
economic loss, or for any claim of such
damage, expenses, or economic loss.
State laws var y. The above
limitations or exclusions may not
apply to you.
For Service
In the USA, call Fieldpiece
Instruments for one-price-fix-all out of
warranty service pricing. Send check or
money order for the amount quoted.
Send the meter freight prepaid to
Fieldpiece Instruments. Send proof
of date and location of purchase for
in-warranty service. The meter will be
repaired or replaced, at the option of
Fieldpiece, and returned via least cost
transportation. Outside of the USA,
please visit www.fieldpiece.com for
service contact information.
AAT3 w/ ET2W
transmitting
wirelessly to HG3
ARH5
In-Duct
Psychrometer
Head
ON
AUTO OFF
1%RH/mVDC
1°F/mVDC
1°C/mVDC
LO BATT
D
P I
R H
P
LO BATT
N
ON
A
D
re ess
ransm tter
C
C
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CF
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HVAC Guide
C
Fieldpiece
D
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m
INPUT FORM
T
R
R
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F
R
F
P
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F
I
ON
ET2W
LO BATT
SEND
RECEIVE
ON
W
T
SYNC
C
S
S
SET
C
S
S
C
HVAC Guide
C
Fieldpiece
S
INPUT FORM
T
R
R
O
F
R
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P
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F
I
ON
T
ON
LO BATT
AV
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ET
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WET
EW
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A TO O
ET2W
LO BATT
SEND
RECEIVE
ON
W
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SYNC
C
S
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SET
C
S
S
C
HVAC Guide
C
Fieldpiece
S
INPUT FORM
T
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ON
T
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LO BATT
AV
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WET
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A TO O
99 Washington Street
Melrose, MA 02176
Phone 781-665-1400
Toll Free 1-800-517-8431
