Extech 42545 Operating Manual

User’s Manual

High Temperature InfraRed Thermometer

with Laser Pointer

MODEL 42545

Introduction

Congratulations on your purchase of the Model 42545 IR Thermometer. The 42545 is
capable of 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.

42545

Safety

• 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

Specifications

Infrared Thermometer Specifications

Range / Resolution -58 to 1832

o

F (-50 to 1000oC) 0.1oC/F to 200°, 1° over 200

Accuracy

Emissivity 0.95 fixed value
Field of View D/S = Approx. 50:1 ratio (D = distance, S = spot)
Laser power Less than 1mW
Spectral response
Over range indication LCD will display “1”

General Specifications

Display 3½ digit backlit LCD display with function indicators
Display rate 1 second approx.
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 6 seconds
Weight/Dimensions 10.2 oz. / 290g 3.9 x 2.2 x 9.0” (100 x 56 x 230mm)

-58 to -4°F ±9°F

-4 to 1000°F ±(2% rdg ± 4oF)
1001 to 1832°F ±(3% rdg ± 9oF)

-50 to -20°C ±5°C

-20 to 538°C ±(2% rdg ± 2oC)
539 to 1000°C ±(3% rdg ± 5oC)
Note: Accuracy is specified for the following ambient

temperature range: 64 to 82°F (18 to 28°C)

6 to 14 µm (wavelength)

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Meter Description

1. Laser pointer beam

2. IR Sensor

3. Measurement Trigger

4. Battery Compartment

5. LCD Display

6. Push-buttons

7. Handle Grip

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Operating Instructions

1. Hold the meter by its Handle Grip and point it toward the surface to be measured.

2. Pull and hold the Trigger to turn the meter on and begin testing. The display will light if
the battery is fresh. Replace the battery if the display does not light.

3. While continuing to pull the Trigger:

a. Push the laser button to turn on the laser pointer. When the laser is on, the

laser icon will appear on the LCD over the temperature reading. Aim the red
beam at the point of test (pressing the laser button again turns the laser off).

b. Select the temperature units using the

o

C or oF button.

c. Push the backlight button to turn on the LCD backlight function.

4. Release the Trigger (the reading will hold for approximately 6 seconds) and the meter
will automatically shut off.

Measurement Notes

1. The object under test should be larger than the spot (target) size calculated by the field
of view diagram.

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 to the
surface before measuring.

4. The meter may not make accurate measurements through transparent surfaces such
as glass.

5. Steam, dust, smoke, etc. can obscure 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
changes.

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.

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Field of View

The meter’s field of view is 50:1. For example, if the meter is 12 inches from the target
(spot), the diameter of the target must be at least .24 inches. Other distance ratios are
shown in the field of view diagram.

The target should always be larger than the spot size. The smaller the target the closer you
should be to take measurements. In instances were accuracy is critical make sure your
target is at least twice the spot size.

Note that measurements should normally be made less than 3 feet from the target. The
meter can measure from further distances but the measurement may be affected by
external sources of light. In addition, the spot size may be so large that it encompasses
surface areas not intended to be measured.

0.5”

Diameter of Spot

0.72”

1”

2”

25”

36”

50”

100”

Distance to Object

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Battery Replacement

When the low battery symbol appears on the LCD, replace the meter’s 9V battery.
The battery compartment is located behind the panel that surrounds the meter’s trigger.
The panel can be pulled open by the two indentations near the trigger and folded down as
shown in the diagram.

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One Year Limited Warranty

EXTECH INSTRUMENTS CORPORATION warrants this instrument to be free of defects
in parts and workmanship for one year from date of shipment (a six month limited warranty
applies to 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
[phone] ext. 210 for authorization or visit our website www.extech.com for contact
information. 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.

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.

All rights reserved including the right of reproduction in whole or in part in any form.

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Copyright © 2004 Extech Instruments Corporation

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