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You have just purchased a
DMM121 digital multimeter
and we thank you for your confidence.
For best results from your instrument:
read
these operating instructions carefully,
comply
with the precautions for use.
PRECAUTIONS FOR USE
This instrument and accessories are compliant with
safety standards IEC 61010-1, IEC 61010-031 and
IEC 61010-2-033 for voltages up to 600V in category III.
Failure to observe the precautions for use and safety
instructions may cause an electric shock, fire, explosion,
or destruction of the instrument and of the installations.
The operator and/or the responsible authority must
carefully read and clearly understand the various
precautions to be taken in use.
If you use this instrument other than as specified, the
protection it provides may be compromised, thereby
endangering you.
Do not use the instrument on networks of which the
voltage or category exceeds those mentioned.
Observe the environmental conditions of use.
Do not exceed the rated maximum voltages and
currents between terminals or with respect to earth.
Do not use the instrument if it seems to be damaged,
incomplete, or poorly closed.
Before each use, check the condition of the insulation
on the leads, housing, and accessories. Any item of
which the insulation is deteriorated (even partially) must
be set aside for repair or scrapping.
Use only the leads and accessories supplied. Using
leads (or accessories) of a lower voltage or category
reduces the voltage or category of the combined
inst leads (or accessories) to that of the leads
(or accessories).
Use personal protective equipment when conditions
require.
When handling the leads, test probes, and crocodile
clips, keep your fingers behind the physical guard.
Keep your hands away from the terminals of the
instrument.
Replace the battery as soon as the
symbol appears
on the display unit. Disconnect all leads before opening
the battery compartment cover.
PRESENTATION
The DMM121 is a device for measuring electrical
quantities:
AC or DC voltage measurement;
DC and AC current measurement;
Frequency measurement;
Capacitance measurement;
Resistance measurement, continuity measurement
with buzzer or diode test.
LCD display
unit
Keys
Input
terminals
Switch
Impact-resistant
jacket
Battery
compartment
cover
Definition of measurement categories
Measurement category IV corresponds to
measurements taken at the source of low-voltage
installations.
Measurement category III corresponds to
measurements on building installations.
Measurement category II corresponds to
measurements taken on circuits directly connected
to low-voltage installations.
USE
IINSERTING THE BATTERIES
See § Maintenance.
TEST OF OPERATION
SELECT
CHANGING RANGES
OFF
OFF
Hz
%
HOLD OF THE DISPLAY
Hz %
Hz %
HZ AND % FUNCTIONS
For AC voltage and current measurements, they are used
to display the frequency and the duty cycle of the signal
measured, respectively.
REL
D
FUNCTION
The REL
D
key is used to subtract the value displayed
at the time the key is pressed from all subsequent
measurements values and to display the result of the
subtraction. This function is not available when “OL” is
displayed.
The automatic power down function of the device is
reactivated when the device is switched back on.
CHANGING MODES
Several modes may be available for a given function
(existence of additional modes indicated by a yellow
symbol). Press the SELECT key to change which mode
is active.
+
SELECT
OFF
OFF
Hz
Diode test
Ω
OFF
OFF
Hz
%
Continuity test
OFF
OFF
Hz
%
+
Ω
R < 90
Ω =
+
Measurement of the frequency of the signal ( )
OFF
OFF
Hz
Measurement of the duty cycle ( )
Hz
%
OFF
OFF
Hz
%
RANGE
SELECT
HOLD
OFF
OFF
REL
Hz %
Hz
%
DMM 121
RANGE
SELECT
HOLD
OFF
OFF
REL
Hz %
Hz
%
DMM 121
30 min
Hz
+
Hz %
Prop
Hz
%
%
Battery
compartment
cover screws
REL
Resistance measurement
BACK-LIGHTING
De-activating the automatic power down
MEASUREMENTS
The input voltage must not exceed 600V.
DC voltage measurement
Capacitance measurement
SWITCHING OFF THE MULTIMETER
Manual switching off
Set the switch to
OFF.
Automatic power down
OFF
OFF
Hz
%
≈
AC voltage measurement
+
+
Resistance and capacitance measurements and
diode and continuity tests must be performed
on voltage-free circuits.
DMM121
Multimeter
SELECT
RANGE
REL
HOLD
Hz %
OFF
OFF
Hz
%
OFF
OFF
Hz
SELECT
SELECT
SELECT
+
SELECT
Ω
SELECT
+
SELECT
RANGE
SELECT
HOLD
MULTIMETER
10A
OFF
OFF
REL
Hz %
Hz
%
DMM 121
RANGE
SELECT
HOLD
MULTIMETER
10A
OFF
OFF
REL
Hz %
Hz
%
DMM 121
GB
WARNING, risk of DANGER! The operator
must refer to this user’s manual whenever this
danger symbol appears.
Equipment protected by double insulation.
Earth.
Instruction that must be read and understood.
AC - Alternating current.
DC - Direct current.
Battery.
The CE marking indicates conformity with
European directives.
The rubbish bin with a line through it means
that in the European Union, the product
must undergo selective disposal for the
recycling of electric and electronic material,
in compliance with Directive WEEE 2002/96/
EC. This equipment must not be treated as
household waste.
OFF
OFF
Hz
%
>2s
AUTO RANGE
AUTO RANGE
RANGE
RANGE
RANGE
HOLD
80 sec.
RANGE
SELECT
HOLD
REL
Hz %
RANGE
SELECT
HOLD
REL
Hz %
RANGE
SELECT
HOLD
REL
Hz %
RANGE
SELECT
HOLD
REL
Hz %
RANGE
SELECT
HOLD
REL
Hz %
RANGE
SELECT
HOLD
REL
Hz %
RANGE
SELECT
HOLD
REL
Hz %
Hz
%
OFF
OFF
Hz
%
RANGE
SELECT
HOLD
REL
Hz %