Introduction

The Fluke 561, 566, and 568 Infrared Thermometers (the "thermometers" or the "Product") are used for non-contact temperature measurements. These thermometers determine an object's surface temperature by measuring the amount of infrared energy radiation emitted by its surface. The thermometers also support contact temperature measurement using a Type K thermocouple. Note that Japanese models indicate Celsius (centigrade) only.

Communicating with Fluke

To contact Fluke, call one of the following numbers:

• US Technical Support: 1-800-44-FLUKE (1-800-443-5853)
• US Calibration and Repair: 1-888-99-FLUKE (1-888-993-5853)
• Canada: 1-800-36-FLUKE (1-800-363-5853)
• Europe: +31 402-675-200
• Japan: +81-3-3434-0181
• Singapore: +65-738-5655
• From any other country: +1-425-446-5500

Alternatively, visit the Fluke website at www.fluke.com.

To register your product, visit http://register.fluke.com.

To view, print, or download the latest manual supplement, visit http://us.fluke.com/usen/support/manuals.

Safety Information

A Warning identifies conditions and actions that pose a hazard to the user; a Caution identifies conditions and procedures that could cause damage to the Product or the equipment being tested, or permanent data loss.

The symbols used on the Product and in this manual are explained in Table 1 and Figures 1 and 2.

⚠️ Warning

To avoid eye damage or personal injury:

• Read the Safety Information before using the product.
• Do not look directly at the laser beam with optical instruments (e.g., binoculars, telescopes, microscopes). Optical instruments concentrate the laser beam, which can be hazardous to the eyes.
• Do not look directly at the laser beam. Do not point the laser beam directly at people or animals, or indirectly at reflective surfaces.
• Do not use laser safety goggles as laser protection goggles. Laser safety goggles only serve to improve the visibility of the laser beam in bright light.
• Do not open the product. The laser beam is hazardous to the eyes. Only approved technical centers should repair the product.
• Replace the batteries when the low battery indicator appears to prevent incorrect measurements.
• The battery compartment must be closed and locked before operating the product.
• Do not use the product if it is not functioning correctly.
• Do not use the product near explosive gases or vapors, or in damp or wet environments.
• Do not connect the optional external probe to energized electrical circuits.
• Consult the emissivity information for actual temperatures. Reflective objects produce lower temperature readings than actual. These objects pose a burn hazard.
• Do not leave the thermometer on or near high-temperature objects.

The use of controls or adjustments, or the use of procedures other than those specified herein, may result in exposure to hazardous laser radiation. Use the product only as specified; otherwise, the protection provided by the product may be ineffective.

⚠️ Caution

To avoid damage to the thermometer or the equipment being tested, protect it from the following:

• Electromagnetic fields from arc welders, induction heaters, etc.
• Static electricity
• Thermal shock (caused by large or abrupt changes in ambient temperature; for greater accuracy, wait 30 minutes for the thermometer to stabilize before use).

Symbols

Table 1. Symbols

Laser Safety Markings

Figures 1 and 2 show the laser safety markings for the 561 and 566/568 models, respectively. These labels provide essential safety information regarding laser exposure, output power, wavelength, and compliance standards.

Features

Model 561 Features:

• Laser focus on a single point.
• Backlit display.
• Current temperature display with MAX, MIN, DIF, AVG.
• Two AA batteries.
• Hard case.
• Type K thermocouple probe 80PK-1 and 80PK-11.
• Adjustable emissivity and predefined emissivity table.
• Display of temperatures measured by the infrared thermometer and the thermocouple.
• Display of temperatures in Celsius or Fahrenheit.
• Tripod mount.
• Automatic power-off.
• Input for standard mini Type K thermocouple connector.
• Printed quick start guide for 56x models.
• 56x Manuals CD.

Models 566 and 568 Additional Features:

• 12 or 24-hour clock.
• Last reading hold (20 seconds).
• Multi-language user interface.
• High and low alarm.
• Data storage and review.
• Trigger lock.
• USB 2.0 computer interface cable (568).
• FlukeView Forms documentation software (568).

Display and Operation

561 Display

The main temperature display shows the current IR temperature or the last IR temperature read for 7 seconds. The secondary temperature display shows the current thermocouple temperature when a Type K thermocouple is connected. When no thermocouple is connected, the small temperature display shows the minimum, maximum, or the difference between maximum and minimum temperatures, as selected. You can switch between minimum, maximum, and differential IR temperature at any time while the display is on. MIN, MAX, and DIF temperatures are calculated and updated continuously when the trigger is pulled. After releasing the trigger, MIN, MAX, and DIF temperatures are held for 7 seconds.

Note: When the battery is low, the B symbol appears on the screen.

The last selection (MIN/MAX/DIF) is retained in the secondary display even after the thermometer is turned off, unless the batteries have failed. Refer to Figure 3.

Display Elements (Figure 3)

Figure 3. Thermometer 561 Display

566/568 Display

The 566/568 thermometer display can show data in the following languages: English, Spanish, French, German, Portuguese, Japanese, Simplified Chinese. To change the displayed language, see "Configuration".

General Menu Overview 566/568

Many settings can be easily changed via the menu. Figure 4 shows the LCD display and menu interface. Selecting the Menu soft key advances the menu to the next level. Table 2 provides a top-level menu description.

Menu Navigation (Figure 4)

Figure 4. Menu Navigation

The display shows the current temperature, settings like HOLD, alarm levels (LO/HI), emissivity (e=0.88), and menu options. The Menu soft key is used to navigate through the settings.

Top-Level Menu Description (Table 2)

Table 2. Top-Level Menu Description

Grdr (Save Function)

To save readings:

1. To take a measurement, pull the trigger.
2. To finish taking the measurement, release the trigger.
3. To enter the Save menu, press the Grdr soft key.
4. Press the Yes soft key to save the reading.

A memory location and a date/time stamp are assigned to the reading. The reading includes: IR temperature, thermocouple temperature (if connected), emissivity, Min/Max/Avg/Diff (if enabled), and Date/Time. You can also press the Cancel soft key to avoid saving the reading.

Luz (Backlight Function)

The thermometers feature a backlit display with two brightness levels. The Luz soft key is used to adjust the backlight brightness. The backlight turns on every time the trigger is pulled. To toggle the backlight brightness, press the Luz soft key.

The backlight can be disabled via the Configuration menu. For more information, consult "Configuration".

Memory

The thermometers can store measurement records including time, date, emissivity, and measurement record numbers. Model 566 can store 20 records, and model 568 can store 99 records. To access stored records: 1. Press the Menu soft key until Mem appears as the left soft key function. 2. To access the Memory menu, press the Mem soft key. Saved readings can be viewed.

Emissivity Menu

The Emissivity Menu includes a list of predefined materials and their typical emissivity values; refer to Tables 3 and 4. For more information, see "Emissivity".

Note: The default emissivity is 0.95.

To access the Emissivity menu:

1. Press the Menu soft key until ε (emissivity) appears as the right soft key function.
2. Press the ε soft key.

The Emissivity list can be accessed by pressing the Tbla soft key, or you can manually enter a material's typical emissivity by pressing the Nro soft key.

• If accessing the emissivity table, a list of materials and their suggested emissivity will appear. Use the Down arrow key to navigate the list. Press the Intro soft key to select the desired material.
• To manually enter an emissivity value: Press the Nro soft key. Use the Up or Down arrow soft keys to modify the entry. Press and hold the arrow soft keys to increase the change speed. Press the Term soft key when finished to return to the main menu.

Emissivity Tables

Table 3. Surface Emissivity (561)

Table 4. Nominal Surface Emissivity (566/568)

* Oxidized
** Opaque, 20 mils or more
*** Natural
**** Factory setting
Highlighted items can also be found in the thermometer's integrated emissivity table.

Temperature Units (°C / °F)

To switch between measurements in °C (Celsius) and °F (Fahrenheit), press the Menu soft key until °C or °F appears as the left soft key function. Press the corresponding soft key to switch between measurements.

Min, Max, Avg, Differential

The thermometers can measure minimum (MIN), maximum (MAX), average (AVG), or differential (Δ) temperatures each time a reading is taken. These values are not displayed if a thermocouple is connected to the thermometer.

To activate Min/Max mode:

1. Press the Menu soft key until MnMx (Min Max) appears as the left soft key function.
2. Press the MnMx soft key.

The display will show the current reading, the maximum and minimum readings, and the emissivity setting.

To activate Avg/Diff mode:

1. Press the Menu soft key until Prom appears as the right soft key function.
2. Press the Prom soft key.

The display will show the current reading, the average reading, the differential reading between Max and Min (indicated by Δ), and the emissivity setting.

Note: Min, Max, Avg, and Differential readings are saved as part of the stored data when either the Min/Max or Avg/Diff modes are enabled.

Alarm

The thermometers have a programmable high and low level alarm to indicate high or low readings based on entered thresholds. When an alarm level is reached, an alarm will sound, and the display will flash orange and white. To configure both high and low level alarms:

1. Press the Menu soft key until Alrm appears as the right soft key function.
2. To access the Alarm menu, press the Alrm soft key.
3. Press either the High or Low soft key, depending on which alarm is to be configured.
4. To activate the alarm, press the ON soft key.
5. To deactivate the alarm, press the OFF soft key.
6. Use the Cnfg soft key to access the configuration menu for high or low level alarms.
7. Use the Up or Down arrow soft keys to modify the alarm setting.
8. Once the desired parameters have been entered, press the Term soft key.

Trigger Lock

The thermometer's trigger can be locked in the on state for continuous measurements. To lock the trigger:

1. Press the Menu soft key until the lock symbol (G) appears as the left soft key function.
2. Press the G soft key to lock the trigger. To indicate a locked trigger, a padlock symbol will appear on the display. When the trigger is locked, the soft key will change to H. Press this soft key to unlock the trigger.

Laser

⚠️ Warning

To avoid eye damage or personal injury:

• Do not look directly at the laser beam. Do not point the laser beam directly at people or animals, or indirectly at reflective surfaces.

The thermometer is equipped with a laser used for aiming only. When the trigger is released, the laser deactivates.

To enable or disable the laser:

1. Press the Menu soft key until Lásr appears as the right soft key function.
2. Press the Lásr soft key to enable or disable the laser. When the laser is enabled, a ⚠️ symbol will appear on the display.

Configuration

In the configuration menu, you can adjust the backlight, date, time, and display language.

Backlight

Under normal use, the backlight is always on. Use this menu to change the backlight setting from on to off. Turning off the backlight conserves battery power.

1. Press the Menu soft key until Cnfg appears as the left soft key function.
2. Press the Cnfg soft key.
3. The Backlight has an indicator next to it. To enter the backlight menu, press the Intro soft key.
4. Press the OFF soft key to turn off the backlight, and press the ON soft key to turn it on.
5. To return to the Configuration Menu, press the Atrs soft key.

Time/Date

To change the time on the thermometer:

1. Press the Menu soft key until Cnfg appears as the left soft key function.
2. To enter the Configuration menu, press the Cnfg soft key.
3. To select Time/Date, press the Down arrow soft key.
4. Press the Intro soft key.
5. Select the Hour soft key.
6. Select the soft key for the desired time format (24hr or 12hr).
7. Use the Up and Down arrow soft keys to change the selected hour to the desired time.
8. To select the minutes, press the Sig soft key.
9. Use the Up and Down arrow soft keys to change the selection to the desired minute.
10. When in 12-hour mode, press the Sig soft key to highlight the am/pm parameter.
11. Use the Up and Down arrow soft keys to change to am or pm.
12. When finished, press the Term soft key. The display reverts to the first page of the Time/Date menu.

To change the date on the thermometer:

1. In the main menu, press the Menu soft key until Cnfg appears as the left soft key function.
2. Press the Cnfg soft key.
3. To select Time/Date, press the Down arrow soft key.
4. Press the Intro soft key.
5. Press the Date soft key.
6. Select the date format: Day/Month/Year (dma) or Month/Day/Year (mda).
7. To modify the selected parameter, use the Up and Down arrow soft keys.
8. Press the Sig soft key and the arrow soft keys to select the corresponding parameters for month, day, or year.
9. To modify the selected parameter, use the Up and Down arrow soft keys.
10. To move to the next parameter, press the Sig soft key.
11. When finished, press the Term soft key. The display reverts to the start of the Time/Date menu.

Language

To change the displayed language:

1. In the main menu, press the Menu soft key until Cnfg appears as the left soft key function.
2. Press the Cnfg soft key.
3. Use the Down arrow soft key to move the indicator to Language.
4. Press the Intro soft key.
5. Use the Down arrow to move the indicator to the desired language.
6. Press the Intro soft key to complete the language selection, or the Back soft key to return to the Configuration Menu.

Data Management

Data Deletion

To delete stored data from the thermometer, in the main menu, press the Menu soft key until Mem appears as the left soft key function. The last memory position is displayed. To access the Delete menu, press the Delete soft key. From here, you can delete all thermometer memory or individual records.

Deleting All Data

To delete all records, press the All soft key. On the confirmation screen, press the Yes soft key.

Deleting Individual Records

To delete individual records, press the View soft key, then use the Down and Up arrow soft keys to access the desired record. Once the desired record is displayed, press the Yes soft key to delete the record. To cancel data deletion, pull the trigger.

Buttons and Connectors

Table 5 shows the buttons and connectors used for the thermometers.

Table 5. Buttons and Connector

How Thermometers Work

Infrared thermometers measure the temperature of an object's surface. The thermometer's optics detect emitted, reflected, and transmitted energy, which is collected and focused onto a detector. The equipment's electronic circuits convert the signal into a temperature reading that is displayed (see Figure 5).

Figure 5. How the Thermometer Works

The diagram illustrates how infrared radiation emitted, reflected, and transmitted by an object is captured by the thermometer's objective lens, focused onto a detector, and converted into a temperature reading.

Thermometer Operation

Temperature Measurement

To measure temperatures, point the thermometer at an object and pull the trigger. You can use the laser pointer to help aim the thermometer. A Type K thermocouple probe can also be inserted for contact measurements. Be sure to consider the distance-to-spot size ratio and the field of view (see "Distance and Spot Size" and "Field of View"). The temperature will appear on the display.

Note: The laser is used for aiming purposes only and is not related to temperature measurements.

The thermometer has an automatic power-off function that turns the unit off after 20 seconds of inactivity. To turn the thermometer on, pull the trigger.

Locating a Hot or Cold Spot

To find a hot or cold spot, point the thermometer away from the desired area. Then, slowly scan the area with an up-and-down motion until the hot or cold spot is found (see Figure 6).

Figure 6. Locating a Hot or Cold Spot

The diagram shows a thermometer scanning an area, with dashed lines indicating the laser pointer and the field of view to locate a specific temperature point.

Distance and Spot Size

As the distance (D) between the thermometer and the measured object increases, the spot size (S) of the area measured by the equipment also increases. The distance-to-spot size (D:S) ratio for each unit is shown in Figure 7. The spot sizes indicate 90% of the encompassed energy.

Figure 7. Distance and Spot Size

The diagrams illustrate the distance-to-spot size ratios (D:S) for models 561 (12:1), 566 (30:1), and 568 (50:1), showing the spot sizes at different distances (e.g., 300mm, 900mm, 1500mm) in both metric and imperial units.

Field of View

For accurate measurements, ensure that the target is larger than the unit's spot size. The smaller the target, the closer you must be (see Figure 8).

Figure 8. Field of View

The diagram shows two scenarios: "Yes" where the target is larger than the field of view, ensuring accurate measurement, and "No" where the target is smaller, leading to potential inaccuracies.

Emissivity

Emissivity describes the energy emission characteristics of materials. Most organic materials and painted or oxidized surfaces have an emissivity of approximately 0.95, the thermometer's default setting. To compensate for inaccurate readings that may occur when measuring shiny metal surfaces, you can cover the surface to be measured with adhesive tape or smooth black paint (<148° C/300° F) with its emissivity set to 0.95. Wait for the tape or paint to reach the same temperature as the surface beneath it. Measure the temperature of the tape or painted surface. If you cannot paint or use tape, you can improve the accuracy of your measurements by either numerically adjusting the emissivity or using the Emissivity Menu to access a table of common materials. The thermometers have a numerically adjustable emissivity from 0.1 to 1.00 that can be used in conjunction with the emissivities in Tables 3 and 4. Additionally, the thermometers have an integrated table of the most common materials that can be configured in the Emissivity Menu. The incorporated values are indicated in Tables 3 and 4.

HOLD Function

When the trigger is released, the display will retain the last infrared measurement for twenty seconds, and HOLD will appear on the display. While the probe is inserted, the contact thermometer remains on. To freeze the infrared temperature when a probe is not inserted, release the trigger until HOLD appears on the display.

Data Storage and Download

Data Storage

The model 566 thermometer can store up to 20 data records. The model 568 thermometer can store up to 99 data records. Each record stores the following information: Record number, IR and probe temperature (°F or °C), Date/Time, Emissivity, Max/Min/Avg/Diff temperature (if enabled). For more information, see "Save".

Data Download

Stored data on the model 568 can be downloaded to a personal computer (PC) via the included USB cable and the included FlukeView® Forms Documenting Software. For details, consult the FlukeView® Forms documentation. The USB 2 input is located on the top of the thermometer, next to the external probe 1 input (see Figure 9).

Note: To prevent incorrect readings, do not take a temperature measurement for a grounded conductor while the 568 is connected to a PC with a ground connection via a three-pin grounded plug.

Figure 9. Thermocouple and USB Connections

The diagram shows the connections for a thermocouple probe (labeled 1) and a USB cable (labeled 2) on the top of the thermometer.

External Contact Probe

⚠️ Warning

To avoid electric shock or personal injury, do not connect the external contact probe to energized electrical circuits.

The thermometers come with a globular Type K thermocouple probe. The probes connect to the thermometer via the probe input located on the top of the unit (see Figure 9). With the probe installed, the probe symbol (A) will appear on the display. The probe can be used simultaneously while the thermometer is taking non-contact measurements. The probe readings are displayed below the non-contact measurements. The thermometer will remain on while a probe is inserted. When used with a personal computer and FlukeView Forms (model 568 only), the automatic power-off function is disabled.

Troubleshooting

Refer to Table 6 for solutions to potential problems when using the thermometer.

Table 6. Troubleshooting

Maintenance

Battery Charging

Use the battery charge symbols to estimate the approximate charge level remaining in the batteries.

Notes:

• In low battery mode, the thermometer does not store values. Attempting to do so will display "Err" on the screen.
• Batteries are at 5%. Before taking additional readings, batteries must be replaced.

Battery Replacement

⚠️ Warning

Batteries contain hazardous chemicals that can cause burns or explode. In case of exposure to chemicals, clean the area with water and call a doctor. To ensure safe operation and maintenance:

• Remove all probes, test leads, and accessories before opening the battery compartment.
• Do not disassemble the battery.
• Repair the product before use if the battery is leaking.
• If the product will not be used for an extended period, remove the batteries to prevent leakage or damage.
• Ensure battery polarity is correct to prevent leakage.
• Do not short the battery terminals, as this could cause a short circuit.
• Do not disassemble or break batteries.
• Do not store batteries where terminals could be short-circuited.
• Do not place batteries near heat sources or fire. Avoid exposure to sunlight.

Note: Batteries should be replaced within one minute of removal to avoid having to manually reset the clock and date on the thermometer.

To install or replace the two AA batteries (see Figure 10):

1. Slide the lock tab on the battery compartment cover to the "Unlock" position and then open the handle.
2. Insert the batteries, observing correct polarity.
3. Close and lock the handle.

Figure 10. Battery Replacement

The diagram illustrates the process of opening the handle, removing old batteries, and inserting new AA batteries with correct polarity.

Lens Cleaning

Remove loose particles using clean compressed air. Carefully clean the surface with a water-dampened cotton swab.

Case Cleaning

Use a soft sponge or cloth dampened with water and soap.

⚠️ Caution

To avoid damaging the thermometers, DO NOT immerse them in water. Do not use abrasive cleaners, as they will damage the case.

User-Replaceable Parts and Accessories

User-Replaceable Parts

For a list of replaceable parts, see Table 7.

Table 7. Replaceable Parts

Accessories

Optional accessories for the thermometers include:

• Flexible carrying case (H6)
• Calibration certification
• All Type K temperature probes with standard mini-connector. For more information, consult Table 8.

Recommended Temperature Probes

For a list of recommended temperature probes, consult Table 8.

Table 8. Recommended Temperature Probes

Specifications

Accessory Details

Accessory 561

Accessory 566/568