Gossen MetraWatt M192A User manual

METRALINE DM 41
Digital Multimeter 3-447-024-03
2/3.21
Operating Instructions

2 Gossen Metrawatt GmbH
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Multimeter Operating Elements
1LCDdisplay
2 Multifunction pushbutton (yellow)
3 Pushbutton for relative value
4 Pushbutton for automatic or manual range selection
5 Hz/% pushbutton for V AC & V DC
6 Pushbutton for Data HOLD function
7 Pushbutton for backlight function (optional)
8 Function selector switch for ON/OFF and measurement
function
9 Terminal sockets
LCD Display
1 Digital display with indication of decimal point and polarity
2 Display of selected current/voltage type
3 Display for automatic measuring range selection
4 REL, HOLD display
5 Continuity test display: buzzer indication
6 Diode measurement display
7 Low battery display
8 Display for unit of measured quantity
Standard Equipment
1Multimeter
1 Protective rubber cover
1Cableset
2 Batteries, 1.5 V, type AA, installed
1 Operating instructions

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Contents Page
1 Safety Features and Safety Precautions ....................................6
2 Initial Start-Up ............................................................................9
3 Function and Range Selection .................................................10
3.1 Measuring Function Selection ..................................................................10
3.2 Automatic Measuring Range Selection .....................................................10
3.3 Manual Measuring Range Selection .........................................................10
4 Liquid Crystal Display (LCD) .....................................................11
4.1 Digital Display .........................................................................................11
4.2 Display with Backlight (Optional) ..............................................................11
5 Buzzer ......................................................................................12
6 Measurement Value Storage „HOLD“ ......................................12
7 REL – Relative Value Measurement .........................................12
8 Voltage Measurement ..............................................................13
9 Current Measurement ..............................................................14
9.1 AC Current Measurement with (Clip-on) Current Transformer ....................15
9.1.1 Transformer Output mA/A .......................................................................15
9.1.2 Transformer Output mV/A .......................................................................16
10 Diode Testing and Continuity Measurement ............................17
10.1 Diode Testing .........................................................................................17
10.2 Continuity Testing ...................................................................................18
11 Resistance Measurement ........................................................19
12
Capacitance Measurement ................................................................. 20
13 Frequency and Duty Cycle Measurement ................................22
13.1 Frequency Measurement .........................................................................22
13.2 Duty Cycle Measurement ........................................................................22
14 Temperature Measurement .....................................................23

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15 Technical Characteristics .......................................................24
16 Maintenance ............................................................................30
16.1 Battery ...................................................................................................30
16.2 Fuses .....................................................................................................32
16.3 Housing ..................................................................................................33
16.4 Returns and Environmentally Sound Disposal ............................................34
17 Product Support .......................................................................35
18 Repair and Replacement Parts Service
Calibration Center* and Rental Instrument Service ................. 35
19 Manufacturer‘s Warranty ......................................................... 36
20 Registration .............................................................................36

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1 Safety Features and Safety Precautions
You have selected an instrument which provides you with a
high level of safety.
The digital multimeter is manufactured in compliance with
safety regulations. In case of incorrect use or careless han-
dling, the safety of both user and multimeter is not assured.
To maintain the safe and proper condition of the multimeters and to
ensure their safe operation, it is absolutely necessary to carefully and
completely read these operating instructions before using any multi-
meter. These instructions must be followed in all respects.
Please observe the following safety precautions
• The multimeter must only be operated by persons who
understand the danger of shock hazards and know how to
apply safety precautions. Shock hazards exist anywhere,
where voltages of more than 30 V (TRMS) may occur.
• Do not work alone in shock hazardous environment while
carrying out measurement
• The maximum allowable voltage between any terminal
sockets (1) and earth is equal to 600 V. Voltages of greater
than 500 V may only be applied to sockets „ “ and „V“
with the selector switch in the voltage measurement posi-
tion (selector switch in „V“ position).
• Take into account that unexpected voltages can occur at
devices under test (e.g. defective devices), for example,
capacitors can be dangerously charged.
• Verify that the test leads are in good condition, e.g. no
cracked insulation, no open circuits in the leads or connec-
tors.
• This multimeter must not be used for measurements on
circuits with corona discharge (high voltage).
• Be particularly careful when measurements are performed in
HF electrical circuits. Dangerous composite voltages may be
present.

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• Measurements under moist ambient conditions are not
permitted.
• Do not exceed the permissible overload limits of the mea-
suring ranges. Limit values can be found in the table „Mea-
suring Ranges“ in chapter 15 „Technical Characteristics“.
• All current ranges are equipped with fuses. The maximum
allowable voltage for the measuring current circuit is equal
to 600 V~.
• The instrument may only be used in power installations when the
electrical circuit is protected with a 20 A fuse or circuit breaker,
and the nominal voltage of the installation does not exceed 600 V.
Meaning of the symbols on the device
Warning concerning a source of danger
(Attention, refer to the operating instructions)
Earth (ground) terminal.
Double or reinforced insulation
CAT II / III / IV Instrument for measuring category II / III or IV
EU conformity mark

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Opening of Equipment / Repair
The equipment may be opened only by authorized service per-
sonnel to ensure the safe and correct operation of the equip-
ment and to keep the warranty valid.
Even original spare parts may be installed only by authorized
service personnel.
In case the equipment was opened by unauthorized person-
nel, no warranty regarding personal safety, measurement
accuracy, conformity with applicable safety measures or any
consequential damage is granted by the manufacturer.
Repair and Parts Replacement by Authorized Service Personnel
After opening the multimeter, live parts may be exposed.
Therefore, the multimeter must be disconnected from the mea-
suring circuit prior to opening its housing for repair, replace-
ment of parts or calibration. If repair or calibration cannot be
avoided unless the multimeter is open and live, this work must
be performed by a qualified person who understands the dan-
gers involved.
Faults and Extraordinary Stress:
If it has been ascertained that safe operation is no longer pos-
sible, take the multimeter out of service and secure it against
accidental use. Safe operation may not be possible
• if the multimeter shows obvious signs of damage,
• if the multimeter no longer functions correctly,
• after prolonged storage under adverse conditions,
• on account of severe stress during transport.

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2 Initial Start-Up
Batteries
Please refer to chapter 16.1 on page 30 before initial start-up
of your instrument or after a lengthy period of storage.
Switching the Multimeter ON
Turn the function selector switch from the OFF position to the
desired measuring function.
All segments of the LCD are activated briefly.
A drawing of the LCD can be found on page 2.
Note!
Electric discharge and high-frequency interference may
cause incorrect displays and block the measuring
sequence. Reset the multimeter by switching it OFF and
ON again. If this procedure is unsuccessful, briefly dis-
connect the battery from the contact terminals.
Attention!
!
Before opening, disconnect the multimeter from the measur-
ing circuit and observe chapter 16 on page 30.
Automatic Meter-OFF (MoFF)
Your multimeter switches OFF automatically after 15 minutes if
no keys or the function selector switch have been activated
during this time.
Switching the multimeter back ON
Activate the HOLD key.
Switching the multimeter OFF
Turn the function selector switch to the OFF position.

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3 Function and Range Selection
3.1 Measuring Function Selection
The desired measuring function is selected with the function
selector switch (white or green print). In order to select the
function printed in green color, the yellow multifunction key
must also be pressed. If the multifunction key is pressed again,
the function printed in white half circle is reactivated.
3.2 Automatic Measuring Range Selection
These multimeters features auto-ranging for all measuring
ranges except for the ranges 400 mV~ and 10 A. Automatic
selection is functional as soon as the multimeter is switched
ON. According to the measured quantity applied, the multime-
ter automatically selects the measuring range which gives the
best resolution.
3.3 Manual Measuring Range Selection
You can switch OFF auto-ranging. Select and fix the ranges
manually according to the table given on page 11.
First select the desired measuring function with the function
selector switch and, if appropriate, the multifunction key.
Briefly activate the AUTO/MAN key.
Manual mode is switched OFF if you press and hold the AUTO/
MAN key until you hear a second acoustic signal, and the dis-
play switches to AUTO.
When switching back to automatic operation in the 400 mV~
range, the 4 V~range is activated.
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Note: For temperature (C), frequency (Hz), duty cycle (%) and
capacitance (F) measuring range is always Auto. No manual
range selection is possible.
4 Liquid Crystal Display (LCD)
4.1 Digital Display
The main digital display shows the measured value, decimal
point and sign. The selected measuring unit and function are
displayed.
When measuring DC quantities, a minus sign appears in front
of the digits, when the positive pole of the measured quantity is
applied to the „ “ input terminal.
„OL“ is displayed if the measuring range upper limit is
exceeded.
The digital display is updated three times per second for V, A,
, Cap., Freq. and duty cycle measurements.
4.2 Display with Backlight (Optional)
By pressing the key, the backlight can be switched ON or
OFF to enable the user to take measurements in poor lighting
conditions.

AUTO
/
MAN
Function
Acknowledge-
ment
Display Acoust.
Signal
brief Manual mode ON:
utilized measuring range is fixed 1 x
brief
V : 400 mV 4V40 V 400 V 600 V 
400 mV 4V
V/: 4 V 40 V400 V600 V 400 mV 
mA : 40 mA 400 mA 40 mA 
mA /:40 mA 400 mA 40 mA 
:40m400 m4k40 k400 k
4m40 m 
1 x
long Return to automatic range selection AUTO 2 x

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5Buzzer
The following steps are acknowledged ba an acoustic signal:
• Activation or deactivation of the following functions:
AUTO/MAN, REL or HOLD, Hz / %, Backlight.
• When AC voltage > 750 V is applied, DC voltage > 1000 V,
AC/DC mA > 400.0 mA, AC/DC A > 10 A, the buzzer
sounds as an overload warning.
• Approximately 1 minute before the multimeter is switched
Auto Power OFF, the buzzer issues constantly 5 acoustic
signals as a sign of warning. Before the multimeter
switches off, the buzzer generates one long acoustic signal
to warn the user.
6 Measurement Value Storage „HOLD“
By pressing the HOLD key, the currently displayed measured
value can be „held“, and „HOLD“ is displayed at the same time
on the LCD.
The HOLD display is switched off if:
• the HOLD key is reactivated,
• the function selector switch is operated,
• the yellow multifunction key is activated for a change of
function, e.g. AC DC,
• the REL key is activated,
• the AUTO/MAN key is activated.
7REL – Relative Value Measurement
The REL key serves to measure relative values and acts in acti-
vation. All functions can be used for relative value measure-
ment except Hz / duty.

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8 Voltage Measurement
➭Turn the function selector switch to V .
➭Connect the measurement cable as shown. Terminal „ “
should be grounded and the second measurement cable
with a higher potential connected to Terminal „V“.
Note!
The 400 mV~measuring range can only be selected
manually with the „AUTO/MAN“ key!
Attention!
!
Ensure that the current ranges („mA“ or „A“) are deactivated
and that the measurement cables are connected with the cor-
rect terminals „V“ and „ “ before connecting your multi-
meter for voltage measurement! If the limit values for
fuse tripping are exceeded due to an operating error,
both the operator and the instrument are in danger!
Ob-
serve the voltage limit values printed on the multimeter!
➭Select the respective voltage type (AC or DC) which corre-
sponds to the measuring value by briefly pressing the yel-
low multifunction key. Each activation of the key causes
alternate switching between AC and DC, as well as ac-
knowledgment by means of an acoustic signal.
The symbols DC and AC indicate the selected voltage type on
the LCD display. After selection of this function with the selector
switch, the voltage type DC is always activated.
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9 Current Measurement
Attention!
!
First of all, disconnect the power supply from the mea-
suring circuit and/or the load and discharge any capac-
itors that might be present.
1 Select function A with the function selector switch for cur-
rents > 400 mA or function mA for currents < 400 mA.
For measuring currents of an unknown quantity, select the high-
est measuring range first.
2 Select the function corresponding to the measured quan-
tity by briefly pressing the yellow multifunction key. Each
time the key is pressed, alternate switching takes place
between AC and DC, and changeover is acknowledged by
an acoustic signal. The symbols DC and AC indicate the
selected current type on the LCD.
After selection of this function with the selector switch, the cur-
rent type DC is always activated.
3 Connect the measuring instrument in series to the load as
shown (without contact resistance).
Notes on Current Measurement:
• The multimeter must be used only in the power systems,
where the current circuit is protected by a fuse or a circuit
breaker of 20 A, and when the nominal voltage of the sys-
tem does not exceed 600 V.
• Carefully secure the measuring circuit connections by
mechanical means so that they do not accidentally open.
The conductor cross sections and connection points
should be designed so as to avoid excessive heating.
• Current ranges up to 400 mA are protected with a
FF1.6 A / 1000 V fuse.
• In the 400 mA measuring range an intermittent acoustic
signal warns you if the measured value has exceeded the
measuring range upper limit value.

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• The 10 A current measuring range is protected by a 10 A /
600 V fuse.
• If a fuse blows, eliminate the cause of the overload before
placing the multimeter back into operation!
• Replacement of the fuses is described in chapter 16.2 on
page 32.
9.1 AC Current Measurement with (Clip-on) Current Transformer
9.1.1 Transformer Output mA/A
Attention!
!
If current transformers are operated with an open circuit
on the secondary side, e. g. due to defective or discon-
nected leads, a blown fuse in the multimeter, or a
wrong connection, dangerously high voltages may
occur at the connectors. Therefore, make sure that the
current circuit of the multimeter and secondary winding
of the transformer connected to the multimeter form an
intact circuit. Connect the transformer to the and mA
or A sockets.
Some current transformers include safety devices which pre-
vent dangerous voltage increases at open electrical circuits.
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The maximum allowable operating voltage at the primary con-
ductor is equal to the nominal voltage of the current trans-
former. When reading the measured value, consider the trans-
formation ratio of the transformer as well as the additional dis-
play error.
9.1.2 Transformer Output mV/A
Some transformers have a voltage output (referred to as mV/
A). The secondary output must therefore be connected to the
connection sockets „“and„V“.
When reading the measured values in V, consider the transfor-
mation ratio of the transformer and the fact that the display
shows current values as well as the additional display error.
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Primary conductor

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10 Diode Testing and Continuity Measurement
10.1 Diode Testing
Attention!
!
Verify that the device under test is electrially dead. Ex-
ternal voltages would falsify the measurement results!
➭Set the function selector switch to „ “.
➭Connect the device under test as shown.
Conducting Direction and Short-Circuit
The measuring instrument displays the forward voltage in volts.
As long as the voltage drop does not exceed the maximum
display value of 1.000 V you can test several elements con-
nected in series.
Reverse Direction or Interruption
The measuring instrument displays a voltage of „OL“.
Note!
Resistors and semiconductor paths in parallel to the
diode distort the measurement results!
Conducting Direction Reverse Direction
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10.2 Continuity Testing
Attention!
!
Verify that the device under test is electrially dead. Ex-
ternal voltages would falsify the measurement results!
➭Set the function selector switch to „ “.
➭Press the yellow multifunction key to switch to the continu-
ity measuring range.
Display of the symbol is activated.
The instrument generates a continuous acoustic signal at a
measured resistance of 0 to approx. < 75 
➭Connect the device under test as shown below.
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11 Resistance Measurement
Attention!
!
Verify that the device under test is electrically dead. Ex-
ternal voltages would falsify the measurement results!
➭Set the function selector switch to „“.
➭Connect the device under test as shown below.
Zero Adjustment (Relative Mode)
In the measurement of resistance, the inherent error of the
multimeter and the resistance of leads can be eliminated by
zero adjustment.
➭Short-circuit the leads connected with the multimeter.
➭Press the REL key.
The instrument acknowledges zero adjustment with an acoustic
signal and values close to 00 and REL are displayed on LCD.
The resistance measured at the time the REL key is pressed
serves as a reference value. This value is then automatically
deducted from all measured values.
Deleting Zero Adjustment
➭Short-circuit the leads connected with the multimeter and
press the REL key afterwards
or activate the function selector switch
or switch the multimeter off.
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12 Capacitance Measurement
Attention!
!
Absolutely verify that the device under test is electrically
dead. External voltages would falsify the measurement
results!
• Set the function selector switch to „F“.
Connect the (discharged!) device under test to sockets „ “
and „F“ with measurement cables. Polarized capacitors must
be connected to the „ “ socket at the „–“ pole.
Note!
Resistors and semiconductor paths in parallel to the
capacitor falsify the measurement results!
To measure small value capacitors, please use short
measurement cables!
If the symbol is displayed, the measured values
are not valid.
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