Velleman DVM821 User manual

DVM821
CAT II 500 V / CAT III 300 V
DIGITAL MULTIMETER - 1999 COUNTS
DIGITALE MULTIMETER - 1999 COUNTS
MULTIMÈTRE NUMÉRIQUE - 1999 POINTS
MULTÍMETRO DIGITAL - 1999 CUENTAS
DIGITAL-MULTIMETER - 1999 ZÄHLUNGEN
MULTIMETR CYFROWY - WARTOŚCI DO 1999
MULTÍMETRO DIGITAL - CONTAGEM ATÉ 1999
USER MANUAL 2
HANDLEIDING 12
MODE D'EMPLOI 22
MANUAL DEL USUARIO 32
BEDIENUNGSANLEITUNG 42
INSTRUKCJA OBSŁUGI 52
MANUAL DO UTILIZADOR 62

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USER MANUAL
1. Introduction
To all residents of the European Union
Important environmental information about this product
This symbol on the device or the package indicates that disposal
of the device after its lifecycle could harm the environment. Do
not dispose of the unit (or batteries) as unsorted municipal waste;
it should be taken to a specialized company for recycling. This
device should be returned to your distributor or to a local
recycling service. Respect the local environmental rules.
If in doubt, contact your local waste disposal authorities.
Thank you for choosing Velleman! Please read the manual thoroughly before
bringing this device into service. If the device was damaged in transit, do
not install or use it and contact your dealer.

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2. Used Symbols
AC (Alternating Current)
DC (Direct Current)
Both AC and DC
Risk of Electric shock. A potentially hazardous voltage is
possible.
Caution: risk of danger, refer to the user manual for safety
information.
Warning: a hazardous condition or action that may result in
injury or death
Caution: condition or action that may result in damage to the
meter or equipment under test
Double insulation (class II-protection)
Earth
Fuse
Capacitor
Diode
Continuity
3. General Guidelines
Refer to the Velleman®Service and Quality Warranty on the last pages
of this manual.
This symbol indicates: Read instructions
Not reading the instructions and manual can lead to damage,
injury or death.
This symbol indicates: Danger
A hazardous condition or action that may result in injury or
death
This symbol indicates: Risk of danger/damage
Risk of a hazardous condition or action that may result in
damage, injury or death

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This symbol indicates: Attention; important information
Ignoring this information can lead to hazardous situations.
WARNING: To avoid electrical shock always disconnect the
test leads prior to opening the housing. To prevent fire hazards,
only use fuses with the same ratings as specified in this manual.
Remark: refer to the warning on the battery compartment
Avoid cold, heat and large temperature fluctuations. When the
unit is moved from a cold to a warm location, leave it switched
off until it has reached room temperature. This to avoid
condensation and measuring errors.
Protect this device from shocks and abuse. Avoid brute force
when operating.
Pollution degree 2-device. For indoor use only. Keep this device
away from rain, moisture, splashing and dripping liquids. Not for
industrial use. Refer to 8. Pollution degree.
Keep the device away from children and unauthorised users.
Risk of electric shock during operation. Be very careful
when measuring live circuits.
There are no user-serviceable parts inside the device.
Refer to an authorized dealer for service and/or spare parts.
This is an installation category CAT III measuring
instrument. Never use this equipment in a CAT IV
environment. Never use the meter with CAT II installations when
measuring voltages that might exceed the safety margin of
500 V above earth ground. Never use the meter with CAT III
installations when measuring voltages that might exceed the
safety margin of 300 V above earth ground. Refer to
7. Overvoltage/installation category.
Read this addendum and the manual thoroughly. Familiarise
yourself with the functions of the device before actually using it.

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All modifications of the device are forbidden for safety reasons.
Damage caused by user modifications to the device is not
covered by the warranty.
Only use the device for its intended purpose. Using the device in
an unauthorized way will void the warranty. Damage caused by
disregard of certain guidelines in this manual is not covered by
the warranty and the dealer will not accept responsibility for any
ensuing defects or problems.
4. Maintenance
There are no user-serviceable parts inside the device.
Refer to an authorized dealer for service and/or spare parts.
•Before performing any maintenance activities, disconnect the test leads.
•For instructions on replacing battery or fuse, refer to 15. Battery
replacement.
•Do not apply abrasives or solvents to the meter. Use a damp cloth and
mild detergent for cleaning purposes.
5. During Use
Risk of electric shock during operation. Be very careful when
measuring live circuits.
•Never exceed the limit value for protection. This limit value is listed
separately in the specifications for each range of measurement.
•Do not touch unused terminals when the meter is linked to a circuit
which is being tested.
•Set the range selector at its highest position if the intensity of the
charge to be measured is unknown beforehand.
•Disconnect the test leads from the tested circuit before rotating the
range selector in order to change functions.
•When carrying out measurements on a TV set or switching power
circuits, always remember that the meter may be damaged by any high
amplitude voltage pulses at test points.
•Always be careful when working with voltages above 60 VDC or 30 VAC
rms. Keep your fingers behind the probe barriers at all times during
measurement.
•Never perform resistance, diode or continuity measurements on live
circuits. Make sure all capacitors in the circuit are depleted.
6. General Description
The DVM821 is a battery-operated, hand-held 3 ½ digital multi-meter for
measuring DC and AC voltages, DC current and resistance. It also offers the

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possibility of executing continuity tests and of testing diodes and transistors.
The back light is optional.
Refer to the illustration on page 2 of this manual:
1. Display (max. 1999 counts, max. 3 ½ digits, dimensions: 47 x 15 mm)
With low-battery indication
2. Rotary switch for manual range selection
This switch is used to select functions and desired ranges as well as to
turn the meter on/off.
3. Input jack
Overvoltage/Installation Category
7. Overvoltage/Installation Category
The applicable categories according EN 61010-1 are:
CAT
II
A CAT II-rated meter is suitable for measurements in CAT I-
environments and mono-phase appliances that are connected to the
mains by means of a plug and circuits in a normal domestic
environment, provided that the circuit is at least 10m apart from a
CAT III- or 20 m apart from a CAT IV-environment. E.g. household
appliances, portable tools…
CAT
III
A CAT III-rated meter is suitable for measurements in CAT I- and
CAT II-environments, as well as for measurements on (fixed) mono-
or poly-phased appliances which are at least 10 m apart from of a
CAT IV-environment, and for measurements in or on distribution
level equipment (fuse boxes, lighting circuits, electric ovens).
8. Pollution Degree
IEC 61010-1 specifies different types of pollution environments, for which
different protective measures are necessary to ensure safety. Harsher
environments require more protection, and the protection against the
pollution which is to be found in a certain environment depends mainly on
the insulation and the enclosure properties. The pollution degree rating of
the DVM indicates in which environment the device may be used.
Pollution
degree 2
Only nonconductive pollution occurs. Occasionally,
temporary conductivity caused by condensation is to be
expected.(home and office environments fall under this
category)
•This device is only suitable for measurements in Pollution
degree class 2 environments.
•operating environment:
otemperature: 0 °C to 40 °C (32 to 104 °F)

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ohumidity: < 80 % RH.
•storage environment:
otemperature: -20 °C to 60 °C (-4 °F to 140 °F)
ohumidity: < 90 % RH
9. Specifications
•overrange: yes
9.1 DC VOLTAGE
Do not measure circuits that may contain voltages
> 500 V
range
resolution
accuracy
200 mV
0.1 mV
± (1.0 % rdg + 2 digits)
2000 mV
1 mV
20 V
10 mV
200 V
100 mV
500 V
1 V
± (1.2 % rdg + 2 digits)
Overload protection: 500 V DC or AC rms
Impedance: 1M Ω
9.2 AC VOLTAGE
Do not measure circuits that may contain voltages
> 500 V
range
resolution
accuracy
200 V
100 mV
± (1.5 % rdg + 3 digits)
500 V
1 V
Average sensing, calibrated to rms of sine wave
Frequency range: 40-500 Hz
Overload protection: 500 V DC or AC rms
Impedance: 450k Ω
9.3 DC CURRENT
Do not measure circuits that may contain voltages
> 500 V
range
resolution
accuracy
2000 µA
1 µA
± (1.5 % rdg + 2 digits)

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20 mA
10 µA
200 mA
100 µA
± (2.0 % rdg + 2 digits)
Overload protection: F0.5 A/600 V
9.4 RESISTANCE
Do not conduct resistance measurements on live
circuits
range
resolution
accuracy
200 Ω
0.1 Ω
± (1.0 % rdg + 5 digits)
2000 Ω
1 Ω
± (1.0 % rdg + 3 digits)
20k Ω
10 Ω
200k Ω
100 Ω
2000k Ω
1k Ω
± (1.5 % rdg + 3 digits)
Overload protection: F0.5 A/600 V fuse
9.5 DIODE AND CONTINUITY
Do not conduct diode or continuity measurements on
live circuits
range
description
test condition
display reads the
approximate forward
voltage of the diode
forward DC current ± 10 µA
reversed DC voltage ± 1.8 V
built-in buzzer sounds
if resistance < 50 Ω
open-circuit voltage ± 1.8 V
Overload protection: F0.5 A/600 V fuse
10. Voltage Measurement
Do not measure circuits that may contain voltages > 500 V

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Use extreme caution when measuring voltages higher than 60 VDC
or 30 VAC rms.
Always place your fingers behind the protective edges of the test
probes while measuring!
10.1 DC VOLTAGE MEASUREMENT
1. Set the rotary switch in the desired V position. If the voltage to be
measured is unknown beforehand, you should set the range switch in
the highest range position and then reduce gradually until the ideal
resolution is obtained.
2. Connect the test leads to the source being measured.
3. Read the voltage value on the LCD display along with the polarity of
the red lead connection.
10.2 AC VOLTAGE MEASUREMENT
1. Set the rotary switch in the appropriate V~ position.
2. Connect the test leads to the source to be measured.
3. Read the voltage value on the LCD display.
Notes
•If the range is not known beforehand, set the selector switch to a high
range and lower gradually.
•An OVER-RANGE is indicated by 1or -1. Set to a higher range.
•The maximum input voltage is 500 V rms.
11. Current Measurement
Do not measure circuits that may contain voltages > 500 V
Use extreme caution when measuring voltages higher than 60 VDC
or 30 VAC rms.
Always place your fingers behind the protective edges of the test
probes while measuring!
1. Set the rotary switch (DCA) in the desired position.
2. Open the circuit in which the current is to be measured and connect
the test leads to the circuit IN SERIES.
3. Read the current value and the polarity of the red lead connection on
the LCD display.
Notes
•If the range is not known beforehand, set the selector switch to a high
range and lower gradually.
•An OVER-RANGE is indicated by 1or -1. Set to a higher range.

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•The maximum input current is 500 mA.
12. Resistance Measurement
Do not conduct resistance measurements on live circuits. Make sure
all capacitors in the circuit are depleted.
1. Set the rotary switch in the appropriate "" range position.
2. Connect the test leads to the resistor to be measured and read the
LCD display.
3. If the resistance being measured is connected to a circuit, turn off the
power and discharge all capacitors before applying the test probes.
13. Diode Testing
Do not conduct diode or continuity measurements on live circuits.
Make sure all capacitors in the circuit are depleted.
1. Set the rotary switch in the " " position.
2. Connect the red test lead to the anode of the diode to be tested and
the black test lead to the cathode of the diode. The approx. forward
voltage drop of the diode will be displayed. If the connection is
reversed, the display will merely show a "1".
14. Continuity Testing
Do not conduct diode or continuity measurements on live circuits.
Make sure all capacitors in the circuit are depleted.
1. Set the range switch in the " " position.
2. Connect the test leads to two points of the circuit to be tested. If
continuity exists, the built-in buzzer will sound.
15. Battery Test
1. Set the range switch in the "1.5 V" or "9 V" position.
2. Connect the test leads to the source to be measured.
3. Read the value on the LCD display.
16. Battery Replacement
WARNING: To avoid electrical shock always disconnect the test
leads prior to opening the housing. To prevent fire hazards, only
use fuses with the same ratings as specified in this manual.
Remark: refer to the warning on the battery compartment