Introduction
Congratulations on your purchase of the Extech 411 (part number EX411) 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.
Safety
International Safety Symbols
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
WARNING
CAUTION
1000V
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) 1000 VAC or VDC.
EX411-EU_ENG V4.0 5/07
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.
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 the children could swallow. In case a child
swallows any of them, please contact a physician immediately
Do not leave batteries and packing material lying around unattended; they can be
dangerous for children if they use them as toys
In case the device is going to be unused for an extended period of time, remove the
batteries to prevent them from training
Expired or damaged batteries can cause cauterization on contact with the skin.
Always, therefore, use suitable hand gloves in such cases
See that the batteries are not short-circuited. Do not throw batteries into the fire.
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OVERVOLTAGE CATEGORY III
00V DC/AC, 200Vrms on 200mV range
This meter meets the IEC 610-1-2001 standard for OVERVOLTAGE CATEGORYIII.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:
Function Maximum Input
mA DC 200mA250V fast acting fuse
ADC 20A 250V fast acting fuse(30 seconds max every 15
Ohms, Continuity 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 1000V 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.
Input Protection Limits
minutes)
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Controls and Jacks
1. Rubber holster
2. 2000 count LCD display
3. °F button
4. °C button
5. Function switch
6. mA, uA and A input jacks
7. COM input jack
8. Positive 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
µ micro (10-6) (amps)
m milli (10-3) (volts, amps)
k kilo (103) (ohms)
M mega (106) (ohms) Ohms
A Amps V Volts
AC Alternating current AUTO Autoranging
DC Directcurrent HOLD Display hold
ºF Degrees Fahrenheit ºC Degrees Centigrade
error
EX411-EU_ENG V4.0 5/07