Triplett IRT350 User Manual

IRT350

Circular Laser IR Thermometer

USER MANUAL

Introduction

Congratulations on your purchase of the Triplett IRT350 12:1 Circular Laser
Infrared Thermometer. This thermometer can quickly and accurately determine
the surface temperature by measuring the infrared energy radiated from the
target surface. The circular laser accurately indicates he target and the area
within it.

Safety

Warnings:

To prevent eye damage or personal
injury, please read the following safety
instructions before using the
thermometer:
Please do not irradiate people or
animals with laser directly or indirectly.
Precautions:
Do not look directly at the laser emitter.
Do not disassemble or modify the thermometer or laser.
To ensure the safety and accuracy of the thermometer, it should only
be repaired by a qualified professional using the original replacement
parts.
If the battery symbol on the LCD display is flashing, please replace the
battery immediately to prevent inaccurate measurement.
Inspect the case before using the thermometer. Do not use the
thermometer if it appears damaged. Look for cracks or missing plastic.
Please refer to the emissivity information for the actual temperature.
Highly reflective objects or transparent materials can cause the
measured temperature value to be lower than the actual temperature.
When measuCircular high temperature surfaces, please be aware not
to touch them.
Do not use the thermometer in an environment close to flammable or
explosive substances.
Using the thermometer around steam, dust, or environments with large
temperature fluctuations may lead to inaccurate temperature
measurement.
To ensure measurement accuracy, please place the thermometer in
the measurement environment for 30 minutes before using.
Avoid keeping the thermometer near a high temperature environment
for long period.

D:S ratio

12:1

MeasuCircular
range

-20°C~600°C/ -4.0°F~1112°F

LCD size

1.2x 1.2” (30mm*30mm)

LCD display

Color EBTN (Enhanced Black Twisted

Nematic)

Accuracy

<0°C: ± (1.5°C+0.1°C/°C);

≥0°C: ±1.5°C or ±1.5% of reading,

whichever is greater

<32°F: ± (3.0°F+0.1°F/°F);

≥32°F: ±3.0°F or ±1.5% of reading,

whichever is greater

Temperature
coefficient

±0.1°C/°C or ±0.1%/°C, whichever is

greater

(±0.1°F/°F or ±0.1%/°F, whichever is

greater)

Repeatability

0.7°C or 0.7%, whichever is greater

(1.5°F or 0.7%, whichever is greater)

Emissivity

0.1~1.0 (adjustable, can store 5 sets of
preset values)

Response time

≤250ms (95% of reading)

Spectral
response

8um~14um

Specifications

Auto power off

15s

Low battery
indication

√

High/Low
temperature
Audible and
LED alarms

√

Data hold

√

Unit
conversion
(°C/°F)

√

MAX/MIN/AV
G/DIF mode

√

Lock
measurement

√

Data storage

99 sets

Scheduled
measurement

Interval from 1 minute to 4 days; up to 99

times

Laser

Circular laser, wavelength 630nm~670nm,

output power <1mW, class 2 laser

Operating
temperature

0°C~50°C (32°F~122°F)

Storage
temperature

-20°C~60°C (-4°F~140°F)

Operating
humidity

<90%RH (non-condensing)

Drop test

1m

Battery type

9V alkaline battery (1604A)

Battery life

≥8 hours (continuous temperature

measurement)

Product net
weight

7.2oz (204g)

Product size

6.3”x 3.5”X1.9”(161.5mm×90mm ×48mm)

**NOTE: In some places with strong electromagnetic interference,
the product measurement result may change by up to ±10°C or 20%
of the measured value (taking whichever is greater).

Safety Standards

CE certification: EN61326-1:2013
Laser safety standard: EN60825-1:2014

Reference Standard

JJG 856-2015

Features

 Circular laser indication, which can indicate the target area under test

more accurately and intuitively

 Bright color EBTN display
 MAX/MIN/AVG/DIF value reading
 5 sets of high/low temperature alarm preset values and 5 sets of

emissivity preset values can be stored for users to set up quickly.

 With tri-color (red, green and blue) LED and buzzer alarm functions
 Lock measurement, for processes that require temperature

monitoCircular

 99 sets of data logging with date and time

 Scheduled measurement, for occasions where timing temperature

monitoCircular is required

 Tripod mount

External Structure

Lock measurement
indicator

Temperature
measurement alarm
indicator

Buzzer indicator

Laser indicator

Temperature hold
indicator

Temperature
measurement
indicator

Low battery
indicator

Temperature unit
indicator

Display Description

Emissivity
indication

Main display of
the measured
temperature

Measurement
mode indication

Auxiliary display
of the measured
temperature

Temperature logging
mode and group
number

Auto

Interval

Scheduled
measurement mark

Date and time

Operating Instructions

 Viewing the Last Measured Value

In the off state, short press (less than 0.5s) the trigger to turn on the
thermometer and the measurement data held before last shutdown
will be displayed. Toggle to view the MAX/MIN/AVG/DIF value by
short pressing the MODE button.

 Auto Power Off

In the HOLD mode, if there is no operation for 15s, the thermometer
will automatically power off and store the currently held
measurement.

 Manual Measurement

1. Pull and hold the trigger after aiming at the target. The SCAN icon
will flash indicating that the target object temperature is being
measured. The measurement result will be updated on the LCD.

2. Release the trigger, the SCAN icon disappears, and the HOLD icon
appears, indicating that the measurement has been stopped and the
last measured value is held.

 Lock Measurement

1. In the HOLD interface, press the SET button for 3s to enter the lock
measurement setting interface, and turn on/off the lock

measurement by pressing the or button. When the lock
measurement is turned on, short press the LOG button to perform
the time setting “00:00” for the lock measurement. At this time, the
selected time position flashes, and the time value can be adjusted by

pressing the or button. Set the time to "00:00" to turn off
timing function.

2. When the lock measurement is turned on, short press the trigger to
enable it. The icon will appear on the thermometer screen and

the SCAN icon will flash. The thermometer will continuously measure
the target temperature.

3. Pull the trigger again, the and SCAN icons disappear, and the
HOLD icon appears. The thermometer stops the measurement and
holds the last measured value.

4. After setting the lock measurement time (1 minute to 5 hours), the
measurement starts after the activation of the lock function. When
the set time is reached, the thermometer will automatically power off
and store the last measured value. Short press (less than 0.5s) the
trigger to turn on the thermometer to view the measured value
(NOTE: The measured value will be cleared by long press).

NOTE: During measurement, it is best to ensure that the measured
target diameter is twice the spot size (S) of the thermometer, and
then determine the test distance (D) according to the D:S diagram
For example, if you use the IRT350 to measure the temperature of
an object with a diameter of about 4’’ (10cm), then according to the
above, the spot size (S) of the thermometer should be about 2’’
(5cm) for highest accuracy, and according to the D:S diagram, the
measured distance (D) is about 24’’ (60 cm).

 Measurement Mode with Data Storage

Function

1. Enter the measurement mode with data storage function:
In the HOLD interface, short press the LOG button to enter the
measurement mode with data storage function. The screen will
display the LOG icon and the log group number.

(With data storage) (Without data storage)

2. Store data:
In the measurement mode with data storage function, first select the

storage location from “01-99” by pressing the or button. If the
selected location has stored data, the temperature value and storage
time will be displayed; if there is no data, "----" will be displayed. After
selecting the location, pull the trigger for measurement. After
completing the measurement, short press the LOG button. The screen
will flash three times to indicate the success of the data storage and
automatically switch to the next location.

3. Query storage data:
In the measurement mode with data storage function, press the
or button to query the storage data and storage time

corresponding to the location. If there is no data, “----” will be
displayed.

4. Delete all storage data:
In the measurement mode with data storage function, long press the
LOG button until the log group number is switched to “01” after 10s
flashing of the screen.

5. Exit the measurement mode with data storage function:
In the measurement mode with data storage function, press the LOG
button for 3s until the screen starts to flash to exit.

 Scheduled Measurement

1. In the HOLD interface, press the SET button for 3s to enter the lock
measurement setting interface, then short press the SET button once
to enter the scheduled measurement setting interface, and turn

on/off the scheduled measurement by pressing the or button.

2. After turning on the scheduled measurement, follow the steps
below to set its parameters:
a) Short press the LOG button to select “Year → Month → Day →
Hour → Minute” in turn to set the start time of the scheduled
measurement. At this time, the selected setting position flashes, and

the value can be adjusted by pressing the or button. NOTE:
The start time cannot be set less than the current system time,
otherwise the scheduled measurement will not be executed.

b) After setting the start time, short press the LOG button to select
“Hour → Minute” in turn to set the interval time of the scheduled
measurement.

c) After setting the interval time, short press the LOG button to set
times (01-99) of the scheduled measurement in turn.

d) After setting the parameters, press the SET button or pull the
trigger to return to the HOLD interface. The Auto Interval icon will
flash. When the start time of the scheduled measurement is reached,
the thermometer will automatically start temperature measurement
and store the current time and measured value. Each time the
interval time is reached, the thermometer will automatically measure
and store the current data, until the last interval.

3. In the HOLD interface, press the LOG button for 3s to enter the
scheduled measurement log value query mode. The screen will
display the Auto Interval icon, the LOG icon and the log group

number. In this mode, press the or button to query the
measured temperature value corresponding to the scheduled time,
press the LOG button for 10s to delete all storage values of the
scheduled measurement, and short press the LOG button or pull the
trigger to exit.

 System Time Setting

In the HOLD interface, press the SET button for 3s to enter the lock
measurement setting interface, and short press the SET button twice
to enter the system time setting interface. Short press the LOG

button to select “Year → Month → Day → Hour → Minute” in turn
and set the corresponding parameters. At this time, the selected
setting position flashes, and the value can be adjusted by pressing the

or button. Add or subtract 1 each time by short press, and add
or subtract 10 per second by long press. Short press the SET button or
pull the trigger to exit the system time setting.

NOTE: System time needs to be reset after battery replacement or
power failure.

 MAX/MIN/AVG/DIF Value Reading

Short press the MODE button to switch the “MAX → MIN → AVG →
DIF” measurement mode in turn and the temperature value of the
corresponding mode will be shown in the auxiliary display area (as
shown below).

 High/Low Temperature Alarm On/Off

Short press the HI/LO button to turn the high/low limit alarm function
on and off in sequence.

When HI limit alarm function is turned on and the measured
temperature value is higher than the set high alarm limit, the red LED
and HI indicator flash. If the audible alarm function has been turned
on, the buzzer will beep.

When LO limit alarm function is turned on and the measured
temperature value is lower than the set low alarm limit, the blue LED
and LO indicator flash. If the audible alarm function has been turned
on, the buzzer will beep.

When HI/LO limit alarm function is turned on and the measured
temperature value is within the high and low alarm limit range, the
green LED lights up and the OK indicator is displayed, indicating that
the measured temperature is normal.

 Function Setting

In setting mode, pull the trigger, short press the SET button
continuously or wait for 10s to exit.

1. High/Low Alarm Limit Setting

In the HOLD interface, short press the SET button once/twice to enter
the high/low alarm limit setting interface. Short press the LOG button
to quickly select the preset high/low alarm limit value (P1-P5). If there
is no desired value among the preset values, select any value closest

to the high/low alarm limit, and adjust it by pressing the or
button. Add or subtract 1 each time by short press, and add or
subtract 10 per second by long press.

2. Emissivity Setting
In the HOLD interface, short press the SET button until the emissivity
setting interface is displayed. Short press the LOG button to quickly
select the preset emissivity value (P1-P5). If no desired value among
the preset values, select any value closest to the emissivity, and

adjust it by pressing the or button. Add or subtract 0.01 each
time by short press, and add or subtract 0.1 per second by long press.

3. Temperature Unit Setting
In the HOLD interface, short press the SET button until the
temperature unit setting interface is displayed, and switch between

°C and °F by pressing the or button.

4. Audible Alarm Setting
In the HOLD interface, short press the SET button until the audible
alarm setting interface is displayed, and turn on/off the audible alarm

by pressing the or button.

5. Laser Indication Function Setting

In the HOLD interface, short press the SET button until the laser
indication function setting interface is displayed, and turn on/off the

laser indication function by pressing the or button. When it is
turned on, the laser indicator will be displayed on the LCD, and

the laser will accurately indicate the position you are measuring the
temperature measurement.

NOTE: Please follow the laser precautions when the laser is turned

D:S=12:1

on to avoid damage to human or animal eyes.

D:S (Distance and Spot Size)

As the distance (D) from the target being measured to the
thermometer increases, the spot size (S) on the measured area
becomes larger. The relationship between the distance and the spot
size is as shown below.

Field of View

Make sure that the measured target is larger than the spot size. The
smaller the target, the closer the test distance should be (please refer
to D:S for the spot size at different distances). To obtain the optimum
measurement result, it is recommended that the target being
measured is 2 times larger than the spot size.

Good

Average

Poor

Target > spot size

Target = spot size
Target < spot size

Emissivity

Emissivity is a symbol of the energy radiation of a material. The
emissivity of most organic materials and coated or oxidized surfaces is
about 0.95. To measure the temperature of a bright metal surface,
cover the surface to be tested with masking tape or matt black paint
with a high emissivity setting (if it is possible), wait for a period of
time, and measure the temperature of the tape or black paint surface
when it reaches the same temperature on the surface of the object
covered below. The total emissivity of some metals and non-metals
are listed in the following table.

Measured Surfaces

Emissivity

Metal

Aluminum
Oxidization

0.2-0.4

A3003 Alloy
Oxidization
Rough

0.3

0.1-0.3

Brass

Burnishing
Oxidization

0.3

0.5

Copper
Oxidization
Electric Terminal
Board

0.4-0.8

0.6

Hastelloy
Alloy

0.3-0.8

Inconel
Oxidization
Sand-Blasting
Electro Burnishing

0.7-0.95

0.3-0.6

0.15

Iron
Oxidization

0.5-0.9

Rusting

0.5-0.7

Iron (Casting)
Oxidization
Non-Oxidization
Casting

0.6-0.95

0.2

0.2-0.3

Iron (Forging)
Passivation

0.9

Lead
Rough
Oxidization

0.4

0.2-0.6

Molybdenum
Oxidization

0.2-0.6

Nickel
Oxidization

0.2-0.5

Platinum
Black

0.9

Steel
Cold Rolling
Steel Plate Rubbing
Steel Plate Burnishing

0.7-0.9

0.4-0.6

0.1

Zinc
Oxidization

0.1

Non-Metal

Asbestos

0.95

Asphalt
Basalt

0.95

0.7

Carbon
Non-Oxidization
Graphite
Silicon Carbide

0.8-0.9

0.7-0.8

0.9

Ceramics

0.95

Clay

0.95

Concrete

0.95

Cloth

0.9

Glass

Convex Glass
Smooth Glass
Lead-Boron Glass

0.76-0.8

0.92-0.94

0.78-0.82

Plates

0.96

Plaster

0.8-0.95

Ice

0.98

Limestone

0.98

Paper

0.95

Plastics

0.95

Water

0.93

Soil

0.9-0.98

Wood

0.9-0.95

Maintenance

 Cleaning

Use clean
compressed air to
blow away falling
particles.
Use wet cotton swab
to carefully wipe lens
surface.
Use wet sponge or
soft cloth to clean
product exterior.
Do not rinse the
thermometer or
immerse it in water.

 Battery Replacement

Install or replace a 9V alkaline battery (1604A) as follows:

1. Open the battery cover.

2. Insert the battery and pay attention to the polarity.

3. Close the battery cover.

Warranty Information

Triplett / Jewell Instruments extends the following warranty to the original purchaser of
these goods for use. Triplett warrants to the original purchaser for use that the products sold
by it will be free from defects in workmanship and material for a period of (1) one year from
the date of purchase.
This warranty does not apply to any of our products which have been repaired or altered by
unauthorized persons in any way or purchased from unauthorized distributors so as, in our
sole judgment, to injure their stability or reliability, or which have been subject to misuse,
abuse,
misapplication, negligence, accident or which have had the serial numbers altered, defaced,
or removed. Accessories, including batteries are not covered by this warranty.

Copyright © 2019 Triplett