Conrad Electronic ME-42 User manual

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Version 12/99
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Digitalmultimeter
ME-42 Seite 4
- 34
Digital Multimeter
ME-42 Page 35
- 64
Multimktre numbrique
ME-42 Page 65
- 98
G9 Digitale multimeter
ME-42
Pagina 99 - 129
Best.-Nr.
/ Item-No. / No de commande / Bestnr.:
12 01 30

0
D
Diese Bedienungsanleitung geh6r-t zu diesem Produkt. Sie
enthslt wichtige Hinweise zur lnbetriebnahme und Handha-
bung. Achten Sie darauf, such wenn Sie dieses Produkt an
Dritte weitergeben.
Bewahren Sie deshalb diese Bedienungsanleitung zum
Nachlesen auf.!
Eine Auflistung der lnhalte finden Sie im lnhaltsverzeichnis
mit Angabe der entsprechenden Seitenzahlen auf Seite 7.
0
GB
These operating instructions belong with this product. They
contain important information for putting it into service and
operating it. This should be noted also when this product is
passed on to a third party.
Therefore look after these operating instructions for future
reference!
A list of contents with page numbers can be found on
page 38.
F
Ce mode d’emploi appartient a ce produit. II contient des
recommandations en ce qui concerne sa mise en service et
samanutention. Veuillez en tenir
compte et ceci egalement
lorsque vous remettez le produit a des tiers.
Conservez ce mode d’emploi afin de pouvoir vous docu-
menter en temps utile.!
Vous trouverez le recapitulatif des indications du contenu i
la table des matieres avec mention de la page correspon-
dante h la page 68.
0
NL Deze handleiding
hoort bij dit product. Zij bevat belangrijke
aanwijzingen voor de inbedrijfstelling en de hantering.
Ne-
em deze aanwijzingen in acht, ook wanneer u dit product
aan derden doorgeeft.
Bewaar daarom deze handleiding zorgvuldig zodat u hem
later kunt raadplegen.!
Een opsomming van de inhoud met aanduiding van de
overeenkomstige paginanummering vindt u op pagina 102.
2

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3

GB
Introduction
DearCustomer,
With the Digital Multimeter ME-42 you have acquired a new-gene-
ration measuring instrument built to the latest technological Stan-
dards.
Construction complies with DIN VDE 0411, part 1 for measu-.
ring instruments
= EN 61010-I. In addition it has been EMC-te-
sted (for domestic use) and fulfils the requirements of the ap-
plicable national and European directives. Conformance to the-
se has been proven; the relevant documents are lodged with
the manufacturer.
To maintain this condition and to guarantee safe operation, the
user must observe these operating instructions without fail!
:
In case of query, consult auf
Technical Advisory Service:
Germany: Tel. +49 (0) f 80 53121 19
Mon - Fri 08.00 to 18.00
Austria: Tel, +43
(0) 72 42
20 30
60
Mon - Thu 08.30
to 12.00, 13.00
to
f6.00
Fri 08.30 to f2.30
Switzerland: Tel, +4f (0)848 87 78 f f
Mon
- Thu 08.00 to f2.00, f3.00 to f 700
Fri 08.00 to
f2.00
35

Intended use of the
Digital Multimeter ME-42:
DC voltage measurement up to a maximum of 1000 VDC
AC voltage measurements up to 750 VAC rms max
Measurement of DC and AC current up to max. 20 A, for a max. of
30 s (protected)
Resistance measurement up to 40 MOhm max
Continuity testing and diode testing.
Measurements must not be performed under unfavourable ambient
conditions. Unfavourable ambient conditions include:
l wetness or excessive humidity,
l dust and combustible gases, fumes or solvents,
l thunderstorms or storm conditions producing strong electrosta-
tic fields, etc.
.-
Any use other than as described above can lead to damage to the
instrument; in addition this is accompanied by dangers such as
short circuit, fire, electric shock, etc. No part of the product must
be modified or converted! The safety instructions are to be follo-
wed without fail !

Operating elements (for illustration see fold-out page)
1
2
3
4
5
6
7
8
9
10
11
12
Unit “ON/OFF” (see also 53.2)
This push button is used to switch the digital multimeter on and
off. The DMM is ready for operation shortly after switching on.
“D-H” push button
(data hold) button = captures the measured value.
“R-H” push button
Holding/switching through the measurement ranges = manual
range selection
Rotary switch (= measuring function switch) for setting the
different operations (voltage measurement, current measure-
ment, etc.).
20 A input
This measuring input is protected with a 20 A fuse and is suita-
ble for DC and AC currents up to max. 20 A (max. 30 s durati-
on with 15 minute pause between measurements).
mA input
This input is for measuring DC and AC currents up to 400 mA
max. (protected with a quick-blow 800mA fuse)
COM (0) input socket (COM or negative connection)
V-Ohm-(+) input socket (= positive connection)
Multifunction LCD display
(3-?&-digit, greatest indication: 3999) with
Analogue bargraph
Bar graph sub-graduations
Overload display
When “OL” appears in the display and an acoustic signal so-
unds, this means overflow = range exceeded (no acoustic sig-
nal during resistance measurement, diode test or temperature
measurement).
Attention!
Observe the maximum input levels.
37

13a “R-H” Range Hold
Range hold means the measurement range is not switched au-
tomatically (auto range), but by hand, manually
13b ‘ID-H” Data Hold
14 -<- = diode test
15 ((a)) = symbol for acoustic continuity test
16 AC = symbol for alternating voltage or current
17
II I II
= minus sign, or symbol for negative polarity
18
= Battery symbol
If this symbol appears in the display, the battery must be chan-
ged
19 Various units of measurement
Contents
Page
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Intended use
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
36
Operating elements (fold-out page) ................................................ 37
Contents .........................................................................................
38
Safety instructions .......................................................................... 39
Presentation
....................................................................................
42
Handling, putting into service
.........................................................
43
Performing measurements
.............................................................
50
Disposal
..........................................................................................
60
Rectification of faults
......................................................................
60
Service and calibration
................................................................... 61
Technical data and measurement tolerances
................................. 62
38

Safety information
Damage resulting from non-observance of this manual renders void
any claim under the guarantee! We accept no responsibility for
consequential damage.
We accept no responsibility for damage to property or injury to per-
sons caused by improper operation or failure to obsen/e the safety
instructions. Such cases void the guarantee.
l This unit is constructed and tested in accordance with DIN 57
411 part IA/DE 0411 part I, safety precautions for electronic
measuring devices or IEC 1010-I and left the factory in sound,
technically-safe condition. To maintain this condition and to en-
sure safe operation, it is essential for the user to observe the sa-
fety instructions and warning notes which are contained in these
operating instructions. The following symbols should be ob-
served:
:c.:
:g..
A
:.i&; .I.!.:
cr
=Attention!
.::.
Dangerous voltages! Danger to life!
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A
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=Read the operating instructions
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CAT II
=Overvoltage categoryII
•l
=Safety class II .’
l Current measurements may only be carried out in circuits which I Y
are themselves fused at 16 A or in which no voltage greater than
250 VDCNACrmsor powers greater than 4000 VA can arise. The
measuring instrument must not be used in installations of Over-
voltage Category III in accordance with IEC 664. The measuring
instrument and instrument leads are not protected against arcing
(IEC 101 o-2-031, Section 13 I Of .I 01).
l Measuring instruments and accessories are not toys and do not
belong in the hands of children!
39

In commercial facilities the accident-prevention regulations of
the Industrial Employers’ Liability Association for electrical sys-
tems and equipment must be observed.
In schools, training facilities, hobby and self-help workshops, the
handling of measuring instruments must be supervised responsi-
bly by trained personnel.
When effecting replacements, it must be ensured that only fuses
of the specified type and specified current rating are used. The
use of a repaired fuse or the bridging of the fuse holder is not
permitted. To change the fuses, disconnect the measuring in-
strument from the circuit being measured and switch it off. Re-
move all connected leads and test probes. Select a suitable
crosspoint screwdriver and carefully open the housing. Remove
the defective fuse(s) and replace with identical type(s) and nomi-
nal current ratings.
0.8 A, quick-blow, 250 V; usual description: F 0.8 A / 250 V or
F800mAI250Vand for the A range 15 A super fast-acting, 250 V;
usual description: FFI 5 A/ 250 V.
Having successfully changed the fuse(s), carefully close and
screw the case up once more, in reverse order.
Only put the measuring instrument into operation once again
when the case is securely closed and screwed up.
Take particular care when dealing with voltages greater than 25
VAC or greater than 35 VDC. Even at these voltages it is possible
to receive a lethal electric shock if electrical conductors are tou-
ched.
Therefore, first of all switch off the voltage source to be mea-
sured, connect the measuring instrument to the voltage source,
set the required measurement range on the unit and only then
switch on the voltage source.
After completing measurements, switch off the voltage source
and remove the test leads from the voltage source connecting
points.
40
-. :

9 Before any voltage measurement, ensure that the measuring
instrument is not set to the current measuring range.
l Before every change in measuring range, the test leads or adap-
ter must be removed from the object being measured.
l Before each measurement check your measuring instrument and
test leads for damage.
l For measurements, only use the test leads which are supplied
with the measuring instrument. Others should not be used.
l To avoid electric shock, care should be taken during measure-
ment not to touch the test probes and the connections (points of
measurement), not even indirectly.
l The voltage between a chosen 4 mm socket of the unit and
ground may not exceed 500 VDCNAC rms.
l The measuring instrument should not be used in areas or under
adverse environmental conditions in which inflammable gas, fu-
mes or dust are present or can occur. For your own safety it is
essential to avoid the measuring instrument or its wiring beco-
ming damp or wet. Avoid operation in the immediate vicinity of:
a) strong magnetic fields (loudspeakers, magnets)
b) electromagnetic fields (transformers, motors, coils, relays,
contactors, electromagnets,etc..)
c) electrostatic fields (charges/discharges)
d) transmission aerials or HF generators
l Do not use the multimeter shortly before, during, or shortly after
a thunderstorm (lightning strike! / high energy overvoltages! En-
sure without fail that the hands, shoes, clothing, floor and the
measuring instrument and its test leads, switches and compo-
nents, etc. are dry.
l If it can be assumed that safe operation is no longer possible,
then the unit must be switched off and protected against unin-
tentional operation. It can be assumed that safe operation is no
41

longer possible if:
- the unit shows visible signs of damage,
- the unit no longer functions and
- after prolonged storage under unfavourable conditions or
- after severe transportation stress.
+ Never switch the unit. on immediately after it has been brought
from a cold into a warm area. The resultant condensation water
could damage the instrument. Allow the instrument to come to
room temperature before switching it on.
P’resentation
This 3 %-digit multimeter with bar graph display has several spe-
cial features which provide a complete picture for many measuring
tasks:
The unit has an AUTO RANGE feature, such that with different
measurements the currently-correct measuring range is always set.
In addition, the DMM can be connected to a PC with an appropri-
ate cable (available as an option) via the built-in interface at its top
end. After installation of the appropriate software onto the PC
(available as an option), communication between the digital multi-
meter and the PC becomes possible.
The 3 3/4-digit liquid crystal display (LCD) allows resolutions of up
to a maximum of 3 digits after the decimal point. The Digital Multi-
meter ME-42 can be used universally in hobby, educational and
(non-industrial) commercial applications, etc.
42

Handling, Putting into operation
A Installation of batteries - changing batteries
For the measuring instrument to function perfectly, it must be fitted
with a 9V battery. When the change-battery symbol appears in the
display, the batteries must be replaced. .Proceed as follows:
Disconnect the unit from the circuit being measured,
remove the measuring leads from the measuring instrument,
switch it off and
with a suitable crosshead screwdriver, unscrew the fixing screws
in the lower part of the case at the centre top, bottom left and
bottom right.
Now carefully remove the cover.
Remove the used battery now revealed from the battery com-
partment,
disconnect it from the connecting clips and
replace the battery with a new one of the same type.
After successfully replacing the battery place it in the battery
compartment and carefully close this once more.
When closing the battery compartment, take care that the
red/black connecting clip leads do not become trapped.
Do not in any event operate the measuring device
when opened! Danger to life!
Do not leave used batteries in the unit, because
even leak-proof batteries can corrode and thereby
release chemicals, which are both damaging to
health and can destroy the battery compartment.
Used batteries are to be treated as waste requiring
special handling and must therefore be disposed of
without harming the environment. Special collection
containers are provided for this purpose by specia-
list dealers and in scrap yards.
43

B Connecting the test leads
When taking measurements, only ever use the supplied instrument
leads or adapters/leads which can optionally be obtained for the
DMM and consequently are matched to it. Before connecting, al-
ways check the condition of the connecting plug and test probes
and check the insulation for damage.
The supplied connecting leads are suitable for voltages up to 1000
V max. The Digital Multimeter ME-42 is designed for voltages to
1000 VDC max. or 750 VAC rms max. Take particular care when
dealing with voltages greater than 25 V AC or 35 V DC.
._
Attentioh!
,:. ::._
A
,.:i’ ::::.
. ...’
!
. . .._ . . .
Never exceed the maximum input levels, because
.... >..:.y ::::jj:::: .,..........
..:-::~l”“‘I::~~::~~~~~:
‘.:::.:.:.:-:.:.. ,_:. ..::,
otherwise damage to the measuring instrument can
endanger life.
C Putting into operation
C 1 Basic setting
Note!
The following text contains numbers in brackets. These num-
bers relate to the description of the operating elements at the
beginning of these instructions.
Press the ON button (1). To select a type of measurement, turn the
rotary switch to the required position.
The built-in acoustic transducer sounds both during continuity
testing below 50 Ohm and when the measuring range is exceeded
(except during
ode testing).
resistancemeasurement/continuitytestingand di-
44

C
4
W
Cl
C
a)
2 Button assignments
The “ON/OFF” button (1) switches the instrument both on and
off: press the button once and the unit will be switched on; press
it a second time and it will be switched off.
In addition a so-called Auto Power Off circuit is incorporated
which automatically switches the instrument off after approx. 15
minutes, to conserve energy.
The display becomes visible again when the instrument is (mecha-
nically) switched off and on again via the “ON/OFF” switch
“,,D - H” (2)
Using this function, changing measured values can be held for a
report. If the “D-H“ is pressed once, the measured value is “fro-
Zen”. Press the button “D-H” again and the display returns to the
instantaneous measurement.
,,R-H” (3) On pressing this button once, the symbol “R-H” (for
Range Hold) appears in the display and the function “Auto Ran-
ge” (= automatic range changing) is no longer active. Each time 1
this button is pressed, with voltage measurement the measure- i
ment range is increased and with resistance measurement the i
range is decreased. The change of range can be seen on the one
hand from the change of unit of measurement and on the other
hand from the position of the decimal point. To return to automa-
tic range change, press the “R-H” button for longer than approx.
1 s. As a result, the symbol “R-H” disappears from the display.
3 Connector and socket configuration
20 A socket
ForDC or AC current measurements (up to 20 A maximum!), the
red test lead must be pluaaed in here.
45

A
Attention!
,..
.,.:.,
1
:.:
1:::;.
The measuring function switch must not on any ac-
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: .A.: :: ,..: r ,.., ‘:.:::.y’.:,
count be positioned on voltage measurement (=-V)
during current measurement.
b) mA socket
For DC or AC current measurement up to 400 mA maximum, the
red test lead must be plugged in here when the measurement
function switch (4) is set either to 4mA or 400mA during current
measurement.
c) COM = Common socket
The black test lead must be plugged in here for all measure-
ments except transistor or temperature measurement (common
socket means minus or ‘-’ or earth socket)
d) V/Ohm socket
The red measuring lead must be plugged ‘into this socket to
carry out voltage, frequency or resistance measurements, conti-
nuity checks and diode tests.
e) Measuring function switch (4) or rotary switch
A
Attention!
j
1
‘:.
:
The measuring function switch must not on any ac-
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. _...
count be moved during measurement, as this can
damage the measuring instrument (separation ar-
cing) and as a result the user may be endangered in
the case of voltages greater than 25 VACrms or 35
VDC.
Arranged in a half circle, the different measuring ranges can be se-
lected by turning the switch:
=v =
DC voltage measurement (auto range)
46
. . . .
. . :- -:

-V
= AC voltage measurement (auto range)
Ohm ((+)) = Continuity testing and resistance measurement (auto
range)
-<- = Diode test (no auto range)
=4mA
= DC current measurement to 4 mA max. (no auto
range
=400mA = DC current measurement to 400
mA max. (no auto
range)
=20A
= DC current measurement to 20 A max. (no auto
range)
-2OA
= AC current measurement to 20 mA max. (no auto
range)
-4mA
= AC current measurement to 4 mA max. (no auto
range)
-4OOmA = AC current measurement to 400 mA max. (no auto
range)
C 4 Display - explanation and symbols
a) Digital Anzeige
The display can indicate up to “3999” and (with negative volta-
ges or reversed polarity) the polarity is automatically indicated
(-). There are also three decimal point positions.
b) Analogue bar graph
The analogue bar graph consists of 42 segments. It has a some-
what higher measuring speed than the digital display. This allows
measured value trends to be more easily recognised than with an
analogue multimeter, but without its mechanical disadvantages
(damping of the measuring unit).
I
If the measurement range is exceeded, then “OL”, for overload,
is displayed. The arrow on the display to the right of the bar
graph flashes.
‘.
:
47
-.
_.

C 5 Operating modes, display details and symbols
a) Diode test
The value displayed during diode test is the forward voltage at
the approx. 1 mA test current. The measuring range here is 0 to
approx. 2.0 V.
b) Continuity testing
In continuity testing, the continuity of voltage-free leads, plug-in
connections or fuses can be checked both acoustically and opti-
cally. An acoustic signal sounds where the resistance is lower
than 50 Ohm.
c) Negative polarity
When the test leads are reversed or with negative polarity, a ‘I-”
sign appears in front of the measured value.
d) “D-H” Data Hold
e) “R-H” (= Range Hold = manual range selection)
After this button is pressed once, the symbol “R-H” (for Range
Hold) appears in the display and the function “Auto Range’ (=
automatic range changing) is no longer active. Each time this
button is pressed, with voltage measurement the measurement
range is increased and with resistance measurement the range is
decreased. The change of range can be seen on the one hand
from the change of unit of measurement and on the other hand
from the position of the decimal point. To return to automatic
range change, press the “R-H” button longer than approx. 1 s.
As a result, the symbol “R-H” disappears from the display.
Attention!
I:.
1
:,.
A
;:
,._,_
This special function is only possible (only selecta-
.::::.:: : .:.::::::
ii..:
:,;y;:..::,.. :.‘::$ii,:
.i:[Jif;~ :.
......... ...
:::..:..:
ble) during DC and AC voltage measurement and
during resistance measurement.
48

f) “Change battery” indicator
An alkaline 9V battery in this measuring device lasts on average
approx. 100 hours. About 8 hours before the battery becomes
empty, the “change battery” indicator appears in the display. A
battery check is performed in between each individual measu-
ring cycle.
g)All remaining symbols indicate the various units of measurement:
AC
= AC value
DC = DC value
mV
= millivolt (exp.-3)
V
= Volt
mA
= milliampere (exp.-3)
A
= ampere
kOhm
= kiloohm (exp.3)
MOhm =
Megohm (exp.6)
D Positioning during use
Always operate the multimeter with the digital display is upwards
so that the liquid crystal display (LCD) can be read. There is a fold-
out bracket on the rear of the unit for better readability in the
uprightposition.
49

Performing measurements
A DC voltage measurement
..::I
A
Attention!
,.j:;;. ..:i,.,
....... ..
. :.y:.:.
1
.:i:;:s;..
Never exceed the maximum permissible input le-
. ...::.
,,:.: :jb::::. ;:.:.:.:...
. . .
,:i~~~~~:;.
i....: .._.. ..
vels, not even when measuring superimposed di-
rect voltages (e.g. ripple voltages): 1000 VDC max.
Do not touch any circuits or circuit components
when measuring voltages higher than 25 V AC rms
or 35 V DC.
For the measurement of DC voltage proceed as follows:
I. Connect the red test lead to the V/Ohm socket and the black
test lead to the COM socket.
2. Set the rotary switch (4) to “V”. This selects the DC voltage mea-
surement mode. The “Auto Range” feature matches the mea-
surement input automatically to the DC voltage present, i.e. the
required measurement range is selected automatically.
3. Connect the test probes to the test object (load, circuit, etc.).
4. The respective polarity of the measured value is shown together
with the present measured value.
The equals “=‘I
sign shows an input resistance of IO MOhm. When
a ” - ”
appears in front of the DC voltage measured value, the mea-
sured voltage is negative (or the test leads are reversed).
Notes!
Due to the fact that the measurement input is very sensitive, it
may be that certain measured values (“phantom measured va-
lues”) are displayed even with test leads unconnected (not
connected to a circuit). This “manifestation” is normal and dis-
appears as soon as a measurement is performed.
50

--
.
B AC voltage measurements
.. ..A
.:.
..
.,
;.I: :‘_::
A
1
(2,. ,..., L.... _......._....
i~~~~~~~
:.:.:.:.:,:.:.>:
: ...... .._.. . . . . .
Attention!
Never exceed the maximum permissible input le-
vels, not even when measuring superimposed di-
rect voltages (e.g. ripple voltages): 750 VAC rms
max.
Do not touch any circuits or circuit components
when measuring voltages higher than 25 V AC rms
or 35 V DC.
For the measurement of AC currents proceed as follows:
1. Connect the red test lead to the V/Ohm socket and the black
test lead to the COM socket.
2. Set the rotary switch (4) to “V”. This selects the AC voltage mea-
surement mode. The “Auto Range” feature matches the mea-
51