General IRT850K User Manual

50:1 ULTRA-WIDE RANGE

IR THERMOMETER

WITH “K” PORT

USER’S MANUAL

IRT850K

99 Washington Street
Melrose, MA 02176

Phone [phone]
Toll Free 1-800-517-8431

Visit us at www.TestEquipmentDepot.com

Please read this manual carefully and thoroughly before using this product.

TABLE OF CONTENTS

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Safety Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Key Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

What’s in the Package. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Product Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Setup Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Install Batteries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Operating Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 –8

Basic Operation in Scan Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 –6

Accounting for Emissivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Other Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 –8

Other Display Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Maintenance Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Warranty Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Return for Repair Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Appendix I: How to Make Accurate IR Measurements . . . . . . . . . . . . . . 10 – 11

Appendix II: Emissivities of Common Materials. . . . . . . . . . . . . . . . . . . . . . . . 12

Manual del Usuario en Español . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 – 24

Manuel de L'utilisateur en Français . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 – 38

INTRODUCTION

Thank you for purchasing General Tools & Instruments’ IRT850K 50:1 Ultra-Wide Range IR
Thermometer with “K” Port. Please read this user’s manual carefully and thoroughly before using
the instrument.

The IRT850K is a specialized instrument that can measure the temperature of a very hot or cold
object or surface (the target) by using an IR sensor to measure its thermal radiation from a safe
distance. Dual laser beams help define the size of the target. With a distance-to-spot (D:S) ratio
of 50:1; the IR sensor can measure the temperature of a target (spot) 1 ft. in diameter from 50 ft.
away with a basic accuracy of ±1.8°F near room temperature and an accuracy of ±(2% of the
reading or 3.6°F) elsewhere in the measurement range. The IRT850K’s IR measurement range is

-76° to 2732°F (-60° to 1500°C).
The IRT also has a socket for an optional “K” type thermocouple probe with a measurement

range as wide as -83.2° to 2552°F (-64° to 1400°C).
The IRT850K is designed for use in heavy industrial sectors such as steel and chemical

manufacturing, petroleum refining, steam generation, and power generation and transmission.

2

SAFETY INSTRUCTIONS

CAUTION - Performing procedures other than those specified in this manual may result in
dangerous radiation exposure.

The IRT850K is a Class 2 laser product that emits less than 1 mW of radiation at a wavelength
between 635 and 660nm. Avoid looking directly at the laser pointers. U.S. law prohibits pointing a
laser beam at aircraft; doing so is punishable by a fine of up to $10,000 and imprisonment.

The lasers may cause discomfort if viewed directly. Your eyes’ natural aversion reflex will prevent
you from looking at the beam long enough to cause harm. As a precaution, keep the IRT850K out
of the hands of children, especially if you have pets.

Never stare at a laser beam through binoculars or a magnifying glass.
Do not operate the IRT in the presence of flammable or explosive gases or in environments full of

dust or static electricity.
Do not operate the unit near a source of a strong electromagnetic field, such as an arc welder or

an induction heater.
Be careful not to burn yourself when attaching a thermocouple probe to a hot surface.

KEY FEATURES

• Extremely wide measurement range

• Adjustable emissivity • Dual targeting lasers

• Port for optional “K” type thermocouple for making contact temperature

measurements

• Releasing trigger automatically holds measurement

• Measurement Lock mode eliminates need to keep squeezing trigger to make multiple

measurements

• Stores/recalls 24 data sets (measured temperature + emissivity setting)

• Min/Max/Avg/Dif displays

• Adjustable Hi and Lo temperature alarm setpoints

• Large backlit dual readout LCD • White LED flashlight • Auto power off

• °C/°F, lasers and flashlight on/off, and backlight on/off buttons

• Battery charge indicator • Tripod mount • CE approved

• 1 year limited warranty

WHAT’S IN THE PACKAGE

The IRT850K comes in a hard plastic protective case along with this user’s manual.
The only optional accessories for the IRT850K available from General are “K” type

thermocouples.

3

PRODUCT OVERVIEW

Figure 1 shows all of the controls, indicators, connectors and other physical features of the
IRT850K. Figure 2 shows a typical measurement display. Familiarize yourself with the positions
and functions of all controls and key components and the meaning of all display indications
before moving on to the Setup Instructions and Operating Instructions.

13. Laser labels (see below right)

3. LCD

1. Emis.
button

2. °C/°F
button

11. “K” probe
socket

4. Lock
button

5. Mode
button

6. Measurement
trigger

7. Battery
compartment

12. Tripod mount

10. LED
flashlight

9. Laser
apertures

8. IR senor
& lens

Fig. 1. The IRT850K’s controls and indicators

and other physical features

1. Emis. (Emissivity) button.

 °C/°F multi-function button. Used to

2.
a) change measurement unit, b) turn targeting lasers and LED flashlight on and off,
c) decrease Hi and Lo alarm setpoints and d) decrement memory location number of recalled data

3. LCD

4.

 Lock multi-function button. Used to a) enter/exit Measurement Lock mode, b) turn LCD

backlight on and off, c) increase Hi and Lo alarm setpoints and d) increment memory location
number of recalled data

5. Mode button. Selects display mode and operating mode

6. Measurement trigger 7. Battery compartment

8. IR sensor and lens 9. Laser apertures

10. LED flashlight 11. Socket for “K” type thermocouple probe with spade lugs

12. Tripod mount 13. Laser Identification/Certification/Warning/Safety labels

Fig. 2. A typical measurement screen.

Note the main (upper) and
secondary (lower) readouts.

4

SETUP INSTRUCTIONS

INSTALL BATTERIES

The IRT850K is ready for use after you install two “AAA” batteries (not included) in the
instrument’s grip. To open the battery compartment (Fig. 1, Callout 7), pull the top of its hinged
cover away from the grip. Then install the two batteries in the compartment, using the + and –
marks inside it as a guide. Close the compartment by swinging the cover back to its original
position and snapping it shut.

OPERATING INSTRUCTIONS

BASIC OPERATION IN SCAN MODE

The IRT850K’s default operating mode is to scan a target object’s surface and display its
temperature.

To make a quick measurement, point the infrared lens on the front of the instrument (Fig. 1,
Callout 8) at a target and squeeze and hold the measurement trigger (Callout 6). The temperature
of the target will instantly appear on the main (upper) readout in the thermometer’s default unit
of degrees Fahrenheit (°F). Before releasing the trigger, note the SCAN icon on the top line of
the display.

Now release the trigger and note that: 1) the main readout will hold the reading for 1 minute (as
indicated by the HOLD indication at the upper left of the LCD); and 2) the IRT will briefly display
the term oFF and then power off. This Auto Power Off (APO) function conserves battery life.

To make an accurate measurement, use the IRT850K’s dual laser beams to define the
diameter of the target. Unlike convergent lasers used to identify the spot distance, the IR850K’s
dual lasers are designed to highlight the spot diameter beyond the focal point (see figure
below)—and therefore the target area—at any distance beyond the spot. This capability is not
just convenient, but also critical in making accurate temperature measurements.

1 ft.

50 ft.

Fig. 3. The IRT850K’s field of view, created by dual diverging laser beams

All IR thermometers, including the IRT850K, take the average temperature of all objects within a
circular target area. Depending on the distance to the target, the target area may include both the
target and background objects in the thermometer’s field of view. If background objects in the
field of view are cooler than the target, the measured temperature will be lower than the target’s

1.5 ft. 2 ft.

75 ft. 100 ft.

5