True RMS Multimeter

Extech EX411A

USER MANUAL

Introduction

Congratulations on your purchase of the Extech EX411A True RMS Multimeter. This meter measures

AC/DC Voltage, AC/DC Current, Resistance, Diode Test, and Continuity plus Thermocouple

Temperature. Proper use and care of this meter will provide many years of reliable service. For copies of this user manual in other languages please visit the www.extech.com

website.

Safety

International Safety Symbols

WARNING

CAUTION

MAX

600V

This symbol, adjacent to another symbol or terminal, indicates the user must refer to the manual for further information.

This symbol, adjacent to a terminal, indicates that, under normal use, hazardous voltages may be present

Double insulation

This WARNING symbol indicates a potentially hazardous situation, which if not avoided, could result in death or serious injury.

This CAUTION symbol indicates a potentially hazardous situation, which if not avoided, may result damage to the product.

This symbol advises the user that the terminal(s) so marked must not be connected to a circuit point at which the voltage with respect to earth ground exceeds (in this case) 600 VAC or VDC.

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CAUTIONS

 Improper use of this meter can cause damage, shock, injury or death. Read and understand this user manual before operating the meter.

 Always remove the test leads before replacing the battery or fuses.

 Inspect the condition of the test leads and the meter itself for any damage before operating the meter. Repair or replace any damage before use.

 Use great care when making measurements if the voltages are greater than 25VAC rms or

35VDC. These voltages are considered a shock hazard.

 Warning! This is a class A equipment. This equipment can cause interference to devices in the home; in this case the operator can be required to carry out adequate measures to prevent interference.

 Always discharge capacitors and remove power from the device under test before performing

Diode, Resistance or Continuity tests.

 Voltage checks on electrical outlets can be difficult and misleading because of the uncertainty of connection to the recessed electrical contacts. Other means should be used to ensure that the terminals are not "live".

 If the equipment is used in a manner not specified by the manufacturer, the protection provided by the equipment may be impaired.

 This device is not a toy and must not reach children’s hands. It contains hazardous objects as well as small parts that children could swallow. In case a child swallows any of the parts, please contact a physician immediately.

 Do not leave batteries and packing material unattended; they can be dangerous for children.

 In case the device is going to be unused for an extended period of time, remove the batteries to prevent them from draining.

 Expired or damaged batteries can cause cauterization on contact with skin. Always use suitable hand protection.

 See that the batteries are not short-circuited. Do not throw batteries into fire.

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OVERVOLTAGE CATEGORY III

This meter meets the IEC 61010-1 (EN61010-1) 3 rd

edition (2010) standard for OVERVOLTAGE

CATEGORY III. Cat III meters are protected against overvoltage transients in fixed installation at the distribution level. Examples include switches in the fixed installation and some equipment for industrial use with permanent connection to the fixed installation.

SAFETY INSTRUCTIONS

This meter has been designed for safe use, but must be operated with caution. The rules listed below must be carefully followed for safe operation.

1. NEVER apply voltage or current to the meter that exceeds the specified maximum:

Input Protection Limits

V DC or V AC mA DC

A DC

Ohms, Continuity

600V DC/AC, 200Vrms on 200mV range

200mA 600V fast acting fuse

10A 600V fast acting fuse (30 seconds max every 15 minutes)

250Vrms for 15sec max

2. USE EXTREME CAUTION when working with high voltages.

3. DO NOT measure voltage if the voltage on the "COM" input jack exceeds 600V above earth ground.

4. NEVER connect the meter leads across a voltage source while the function switch is in the current, resistance, or diode mode. Doing so can damage the meter.

5. ALWAYS discharge filter capacitors in power supplies and disconnect the power when making resistance or diode tests.

6. ALWAYS turn off the power and disconnect the test leads before opening the covers to replace the fuse or battery.

7. NEVER operate the meter unless the back cover and the battery cover is in place and fastened securely.

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Description

2. 2000 count LCD display

6. mA, uA and A input jacks

7. COM input jack

9. Battery check button

10. Hold button

11. Backlight button

Note: Tilt stand and battery compartment are on rear of unit.

Symbols and Annunciators

•))) Continuity

Diode test

Battery status

Test lead connection error

2

3

4

5

A Amps

DC

ºF

Direct current

Degrees Fahrenheit



Ohms

HOLD Display hold

ºC Degrees Centigrade

1

6 7

10

9

11

8

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Operating Instructions

WARNING: Risk of electrocution. High-voltage circuits, both AC and DC, are very dangerous and should be measured with great care.

1. ALWAYS turn the function switch to the OFF position when the meter is not in use.

2. If “1 ” appears in the display during a measurement, the value exceeds the range you have selected. Change to a higher range.

NOTE: On some low AC and DC voltage ranges, with the test leads not connected to a device, the display may show a random, changing reading. This is normal and is caused by the high-input sensitivity. The reading will stabilize and give a proper measurement when connected to a circuit.

DC VOLTAGE MEASUREMENTS

CAUTION: Do not measure DC voltages if a motor on the circuit is being switched ON or OFF.

Large voltage surges may occur that can damage the meter.

1. Set the function switch to the highest V DC ( ) position.

2. Insert the black test lead banana plug into the negative COM jack.

Insert the red test lead banana plug into the positive V jack.

3. Touch the black test probe tip to the negative side of the circuit.

Touch the red test probe tip to the positive side of the circuit.

4. Read the voltage in the display. Reset the function switch to successively lower V DC positions to obtain a higher resolution reading. If the polarity is reversed, the display will show (-) minus before the value.

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AC VOLTAGE MEASUREMENTS

WARNING: Risk of Electrocution. The probe tips may not be long enough to contact the live parts inside some 240V outlets for appliances because the contacts are recessed deep in the outlets. As a result, the reading may show 0 volts when the outlet actually has voltage on it. Make sure the probe tips are touching the metal contacts inside the outlet before assuming that no voltage is present.

CAUTION: Do not measure AC voltages if a motor on the circuit is being switched ON or OFF.

Large voltage surges may occur that can damage the meter.

1. Set the function switch to the highest V AC ( ) position.

2. Insert the black test lead banana plug into the negative COM jack.

Insert red test lead banana plug into the positive V jack.

3. Touch the black test probe tip to the neutral side of the circuit.

Touch the red test probe tip to the “hot” side of the circuit.

4. Read the voltage in the display. Reset the function switch to successively lower V AC positions to obtain a higher resolution reading.

DC CURRENT MEASUREMENTS

CAUTION: Do not make current measurements on the 10A scale for longer than 30 seconds.

Exceeding 30 seconds may cause damage to the meter and/or the test leads.

1. Insert the black test lead banana plug into the negative COM jack.

2. For current measurements up to 200µA DC, set the function switch to the 200µA DC ( ) position and insert the red test lead banana plug into the uA/mA jack.

3. For current measurements up to 200mA DC, set the function switch to the 200mA DC position and insert the red test lead banana plug into the

uA/(mA jack.

4. For current measurements up to 10A DC, set the function switch to the

10A DC range and insert the red test lead banana plug into the 10A jack.

5. Remove power from the circuit under test, then open up the circuit at the point where you wish to measure current.

6. Touch the black test probe tip to the negative side of the circuit.

Touch the red test probe tip to the positive side of the circuit.

7. Apply power to the circuit.

8. Read the current in the display.

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AC CURRENT MEASUREMENTS

CAUTION: Do not make current measurements on the 10A scale for longer than 30 seconds.

Exceeding 30 seconds may cause damage to the meter and/or the test leads.

1. Insert the black test lead banana plug into the negative COM jack.

2. For current measurements up to 200mA AC, set the function switch to the highest 200mA AC ( ) position and insert the red test lead banana plug into the mA jack.

3. For current measurements up to 10A AC, set the function switch to the

10A AC range and insert the red test lead banana plug into the 10A jack.

4. Remove power from the circuit under test, then open up the circuit at the point where you wish to measure current.

5. Touch the black test probe tip to the neutral side of the circuit.

Touch the red test probe tip to the “hot” side of the circuit.

6. Apply power to the circuit.

7. Read the current in the display.

RESISTANCE MEASUREMENTS

WARNING: To avoid electric shock, disconnect power to the unit under test and discharge all capacitors before taking any resistance measurements. Remove the battery and unplug the line cords.

1. Set the function switch to the highest

 position.

2. Insert the black test lead banana plug into the negative COM jack.

Insert the red test lead banana plug into the positive

 jack.

3. Touch the test probe tips across the circuit or part under test. It is best to disconnect one side of the part under test so the rest of the circuit will not interfere with the resistance reading.

4. Read the resistance in the display and then set the function switch to the lowest

 position that is greater than the actual or any anticipated resistance.

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CONTINUITY CHECK

WARNING: To avoid electric shock, never measure continuity on circuits or wires that have voltage on them.

1. Set the function switch to the position.

2. Insert the black lead banana plug into the negative COM jack.

Insert the red test lead banana plug into the positive

 jack.

3. Touch the test probe tips to the circuit or wire you wish to check.

4. If the resistance is less than approximately 150

, the audible signal will sound. If the circuit is open, the display will indicate

“1”.

DIODE TEST

1. Insert the black test lead banana plug into the negative COM jack and the red test lead banana plug into the positive diode jack.

2. Turn the rotary switch to the position.

3. Touch the test probes to the diode under test. Forward bias will typically indicate 400 to 1000. Reverse bias will indicate “1 ”.

Shorted devices will indicate near 0 and the continuity beeper will sound. An open device will indicate “1 ” in both polarities.

9

1

2

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TEMPERATURE MEASUREMENTS

1. Set the function switch to the TEMP position.

2. Insert the Temperature Probe into the Temperature Socket, making sure to observe the correct polarity.

3. Press the ºC or ºF button for the desired units.

4. Touch the Temperature Probe head to the part whose temperature you wish to measure. Keep the probe touching the part under test until the reading stabilizes.

5. Read the temperature in the display.

Note: The temperature probe is fitted with a type K mini connector. A mini connector to banana connector adaptor is supplied for connection to the input banana jacks.

DISPLAY BACKLIGHT

Press and hold the button to turn on the display backlight function.

The backlight will automatically turn off after 15 seconds.

BATTERY CHECK

The CHECK function tests the condition of the 9V battery. Set the function switch to the

200VDC range and press the CHECK button. If the reading is less than 8.5, battery replacement is recommended.

HOLD

The hold function freezes the reading in the display. Press the HOLD key momentarily to activate or to exit the hold function.

AUTO POWER OFF

The auto off feature will turn the meter off after 15 minutes.

LOW BATTERY INDICATION

If the icon appears in the display, the battery voltage is low and the battery should be replaced.

WRONG CONNECTION INDICATION

The icon will appear in the upper right conner of the display and the buzzer will sound whenever the positive test lead is inserted into the 10A or uA/mA input jack and a non-current

(green) function is selected. If this occurs, turn the meter off and reinsert the test lead into the proper input jack for the function selected.

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Specifications

DC Voltage

(V DC)

200mV 0.1mV

Accuracy

(0.3% reading + 2 digits)

AC Voltage

(V AC)

(True rms)

DC Current

(A DC)

AC Current

(A AC)

(True rms)

200V 0.1V

600V 1V (0.8% reading + 2 digits)

50 to 400Hz

2V 0.001V

(1.0% reading +6

400Hz to 1kHz

(2.0% reading + 8 digits

200V 0.1V

600V 1V digits

(1.5% reading +6 digits

(2.0% reading +6 digits

(2.5% reading +8 digits

(3.0% reading +8 digits

200

A 0.1A

200mA 0.1mA

(1.5% reading + 3 digits)

10A 0.01A

(2.5% reading + 3 digits)

50 to 400Hz 400Hz to 1kHz

200mA 0.1mA

(1.8% reading +8 digits (2.5% reading +10 digits)

Resistance

10A 0.01A (3.0% reading +8 digits)

200

 0.1

2000



1



20k

 0.01k

200k

 0.1k

20M

 0.01M

Temperature -20

750ºC

-4 to 1382ºF 1ºC

(0.8% reading +4 digits)

(0.8% reading +2 digits)

(1.0% reading +2 digits)

(2.0% reading +5 digits)

(3.0% reading +3 digits)

(3.5% reading +10 digits)

(meter only, probe accuracy not included)

NOTE: Accuracy specifications consist of two elements:

 (% reading) – This is the accuracy of the measurement circuit.

 (+ digits) – This is the accuracy of the analog to digital converter.

NOTE: Accuracy is stated at 18 o C to 28 o C (65 o F to 83 o F) and less than 75% RH.

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General Specifications

Diode Test

Continuity Check

Test current of 1mA maximum, open circuit voltage 2.8V DC typical

Audible signal will sound if the resistance is less than approximately

150



Input Impedance 10MΩ

AC Response

True rms

ACV Bandwidth

50Hz to 1kHz

DCA voltage drop

Display

Auto-Power Off

200mV

3 ½ digit, 2000 count LCD, 0.9” digits

15 minutes (approximately)

Overrange indication

Polarity

“1” is displayed

Automatic (no indication for positive polarity); Minus (-) sign for negative polarity.

Measurement Rate

2 times per second, nominal

Low Battery Indication “ ” is displayed if battery voltage drops below operating voltage

Battery

Fuses

One 9 volt (NEDA 1604) battery mA, µA ranges; 0.2A/600V fast blow

A range; 10A/600V ceramic fast blow

Operating Temperature 5ºC to 40ºC (41ºF to 104ºF)

Storage Temperature

-20ºC to 60ºC (-4ºF to 140ºF)

Operating Humidity

Storage Humidity

Operating Altitude

Weight

Size

Safety

Max 80% up to 31ºC (87ºF) decreasing linearly to 50% at 40ºC (104ºF)

<80%

2000 meters (7000ft.) maximum

342g (0.753lb) (includes holster)

187 x 81 x 50mm (7.36” x 3.2” x 2.0”) (includes holster)

For indoor use and in accordance with the requirements for double insulation to IEC 61010-1 (EN61010-1) 3 rd edition (2010); Overvoltage

Category III 600V; Pollution Degree 2.

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Maintenance

WARNING: To avoid electrical shock, disconnect the meter from any circuit, remove the test leads from the input terminals, and turn OFF the meter before opening the case. Do not operate the meter with an open case.

This MultiMeter is designed to provide years of dependable service, if the following care instructions are performed:

1. KEEP THE METER DRY. If it gets wet, wipe it off.

2. USE AND STORE THE METER IN NORMAL TEMPERATURES. Temperature extremes can shorten the life of the electronic parts and distort or melt plastic parts.

3. HANDLE THE METER GENTLY AND CAREFULLY. Dropping it can damage the electronic parts or the case.

4. KEEP THE METER CLEAN. Wipe the case occasionally with a damp cloth. DO NOT use chemicals, cleaning solvents, or detergents.

5. USE ONLY FRESH BATTERIES OF THE RECOMMENDED SIZE AND TYPE. Remove old or weak batteries so they do not leak and damage the unit.

6. IF THE METER IS TO BE STORED FOR A LONG PERIOD OF TIME, the batteries should be removed to prevent damage to the unit.

Battery Replacement

1. Remove the Phillips head screw that secures the rear battery door

2.

3.

Open the battery compartment

Replace the 9V battery

4. Secure the battery compartment

Never dispose of used batteries or rechargeable batteries in household waste. 

As consumers, users are legally required to take used batteries to appropriate  collection sites, the retail store where the batteries were purchased, or wherever  batteries are sold. 

Disposal: Do not dispose of this instrument in household waste. The user is obligated to take end‐

of‐life  devices  to  a  designated  collection  point  for  the  disposal  of  electrical  and  electronic 

  equipment.  

Other Battery Safety Reminders 

o Never dispose of batteries in a fire. Batteries may explode or leak.  o Never mix battery types. Always install new batteries of the same type. 

WARNING: To avoid electric shock, do not operate the meter until the battery cover is in place and fastened securely.

NOTE: If your meter does not work properly, check the fuses and batteries to make sure that they are still good and that they are properly inserted.

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REPLACING THE FUSES

WARNING: To avoid electrical shock, disconnect the meter from any circuit, remove the test leads from the input terminals, and turn OFF the meter before opening the case. Do not operate the meter with an open case.

1. Disconnect the test leads from the meter.

2. Remove the protective rubber holster.

3. Remove the battery cover (two “B” screws) and the battery.

4. Remove the four “A” screws securing the rear cover.

5. Lift the center circuit board straight up from the connectors to gain access to the fuse holders.

6. Gently remove the old fuse and install the new fuse into the holder.

7. Always use a fuse of the proper size and value

(0.2A/600V fast blow for the 200mA range,

10A/600V fast blow for the 10A range).

8. Align the center board with the connectors and gently press into place.

9. Replace and secure the rear cover, battery and battery cover.

WARNING: To avoid electric shock, do not operate your meter until the fuse cover is in place and fastened securely.

Copyright © 2013‐2016 FLIR Systems, Inc. 

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

ISO‐9001 Certified 

www.extech.com 

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