EXTECH 42529

User’s Manual
InfraRed Thermometer
with Laser Pointer
MODEL 42529
Congratulations on your purchase of the Model 42529 IR Thermometer. This thermometer
makes non-contact (infrared) temperature measurements at the touch of a button. The
built-in laser pointer increases target accuracy while the backlit LCD and handy pushbuttons combine for convenient, ergonomic operation. Proper use and care of this meter
will provide years of reliable service.
EXTECH INSTRUMENTS CORPORATION warrants this instrument to be free of defects in parts and
workmanship for three (3) years from date of shipment (a six month limited warranty applies on sensors and
cables). If it should become necessary to return the instrument for service during or beyond the warranty
period, contact the Customer Service Department at (781) 890-7440 ext. 210 for authorization or visit our
website at www.extech.com (click on ‘Contact Extech’ and go to ‘Service Department’ to request an RA
number). A Return Authorization (RA) number must be issued before any product is returned to Extech. The
sender is responsible for shipping charges, freight, insurance and proper packaging to prevent damage in
transit. This warranty does not apply to defects resulting from action of the user such as misuse, improper
wiring, operation outside of specification, improper maintenance or repair, or unauthorized modification. Extech
specifically disclaims any implied warranties or merchantability or fitness for a specific purpose and will not be
liable for any direct, indirect, incidental or consequential damages. Extech's total liability is limited to repair or
replacement of the product. The warranty set forth above is inclusive and no other warranty, whether written or
oral, is expressed or implied.
Use extreme caution when the laser pointer beam is on
Do not point the beam toward anyone's eye or allow the
beam to strike the eye from a reflective surface
Do not use the laser near explosive gases or in other
potentially explosive areas
Infrared Thermometer Specifications
Range / Resolution
0 to 600 F (-20 to 320 C)
± 2% of reading or ± 4 F (2 C) whichever is greater.
1 C/F
Note: Accuracy is specified for the following ambient
temperature range: 64 to 82°F (18 to 28°C)
0.95 fixed value
Field of View
D/S = Approx. 6:1 ratio (D = distance, S = spot)
Laser power
Less than 1mW
Spectral response
6 to 14 µm (wavelength)
General Specifications
3½ digit backlit LCD display with function indicators
Display rate
1 second approx.
Over range indication
Audible tone sounds and ‘OVER’ appears on the LCD when
the measurement exceeds the measurement range spec.
Operating Temperature
32°F to 122°F (0°C to 50°C)
Operating Humidity
Max. 80% RH.
Power Supply
9V battery
Automatic Power Off
Meter shuts off automatically after 7 seconds
6.35 oz. / 180g
8.3 x 3.5 x 1.5” (211 x 89 x 38mm)
Model 42529 Version 1.9 November 2005
Meter Description
1. LCD Display
2. Function Buttons
3. Handle Grip
4. Laser Pointer
5. IR Sensor
6. Measurement Trigger
7. Battery Compartment
Operating Instructions
1. Hold the meter by its Handle Grip and point it toward the device whose temperature is
to be measured.
2. Press and hold the red Trigger to turn the meter on and begin testing. The display will
light if the battery is charged. Replace the battery if the display does not light.
3. While continuing to press the Trigger, push the red Laser button to turn on the laser
pointer. Aim the red beam approximately a half inch higher than the point of test as
shown in the diagram below (pressing the Laser button again turns the laser off).
4. While measuring, the SCAN display icon will appear on the LCD above the
temperature measurement and to the left of the emissivity value (fixed at 0.95.).
5. If the measurement exceeds the useable temperature range (0 to 600 F), the meter will
emit a tone and the LCD will display ‘OVER’.
6. Release the Trigger when the temperature stabilizes. The HOLD display icon will
appear on the LCD indicating that the reading is being held.
7. Set the temperature units ( C or F) using the blue C and F buttons.
8. Press the yellow Backlight key to turn on the LCD backlighting function.
9. The meter will automatically power down after 7 seconds.
Field of View
The meter’s field of view is 6:1, meaning that if the meter is 6 inches from the target, the
diameter of the object under test must be at least 1 inch. Other distances are shown below
in the field of view diagram. Refer to the chart printed on the meter for more information.
Distance to Object
Laser Beam
Sensor Beam
Diameter of Spot
Model 42529 Version 1.9 November 2005
Measurement Notes
1. The object under test should be larger than the spot (target) size calculated by the field
of view diagram (see diagram on previous page or on side of the meter).
2. If the surface of the object under test is covered with frost, oil, grime, etc., clean before
taking measurements.
3. If an object's surface is highly reflective apply masking tape or flat black paint before
4. The meter cannot measure through transparent surfaces such as glass.
5. Steam, dust, smoke, etc. can obscure accurate measurements.
6. The meter compensates for deviations in ambient temperature. It can, however, take
up to 30 minutes for the meter to adjust to extremely wide ambient temperature
7. To find a hot spot, aim the meter outside the area of interest then scan across (in an up
and down motion) until the hot spot is located.
Battery Replacement
When the low battery symbol
appears on the LCD, replace the meter’s 9V battery.
The battery compartment is located on the bottom of the meter's handle. Open the
compartment by sliding the battery compartment cover off in the direction of the arrow.
Replace battery and re-install the battery compartment cover.
Calibration and Repair Services
Extech offers repair and calibration services for the products we sell. Extech also
provides NIST certification for most products. Call the Customer Service Department for
information on calibration services available for this product. Extech recommends that
annual calibrations be performed to verify meter performance and accuracy.
Support line (781) 890-7440
Technical support: Extension 200; E-mail: [email protected]
Repair & Returns: Extension 210; E-mail: [email protected]
Product specifications subject to change without notice
For the latest version of this User’s Guide, Software updates, and other
up-to-the-minute product information, visit our website: www.extech.com
Extech Instruments Corporation, 285 Bear Hill Rd., Waltham, MA 02451
Copyright © 2005 Extech Instruments Corporation
All rights reserved including the right of reproduction in whole or in part in any form.
Model 42529 Version 1.9 November 2005