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life, the battery change symbol appears in the display.
A battery check is carried out each time between individual measu-
rement cycles.
g) all other symbols, which stand for the various measurement units:
AC
=
AC units
DC
=
DC units
mV
=
millivolt (exp.-3)
V
=
Volt
mA
=
milliampere (exp.-3)
A
=
Ampere
kHz
=
kilohertz (exp.3)
uF
=
microfarad (exp.-6)
nF
=
nanofarad (exp.-9)
mH
=
milliHenry (exp.-3)
uH
=
mikroHenry (exp.-6)
W
=
Ohm
kW
=
kiloohm (exp.3)
MW
=
Megaohm (exp.6)
5.4.3 Performing measurements
A) Voltage measurement
Attention!
Under no circumstances exceed the maximum permitted input ampli-
tude. 1000 VDC max. and 750 VAC rms max.
Touch no circuits or components when voltages greater than 25 VAC rms
or 35 VDC are present.
To measure DC or AC voltages, proceed as follows:
1. Set the rotary switch to the desired position (mV or V)
2. Connect the red test lead to the V/Ohm socket (+) and the black
test lead to the COM socket (-)
3. Press the DC/AC button according to whether DC or AC voltage is
to be measured. As soon as "AC" appears in the display, the AC vol-
tage measurement range is set.
4. Connect the test probes to the points of measurement (load, cir-
cuit, etc.).
34
Each of the five voltage ranges, whether AC or DC, has an input impe-
dance of 10 MOhm in parallel with 100 pF. The AC voltage input is AC-
coupled. As soon as a "-"-sign appears in front of the measured value
under DC voltage measurements, the measured voltage is negative
(or the test leads reversed).
B) Current measurement
To measure direct or alternating currents, procedure is as follows:
1. Set the rotary switch to current measurement (400mA or 20A).
2. Connect the red test lead to the mA socket when currents up to 400
mA max. are to be measured and to the A socket for currents up to
20 A max.
3. Press the DC/AC button according to whether DC or AC current is
now to be measured.
As soon as "AC" appears in the display, the AC current measure-
ment range is set.
4. Connect the instrument leads in series with the test object (see figu-
re below).
Attention!
Do not measure any currents in circuits in which voltages greater than
250 VDC or VAC rms can occur. Under no circumstances should currents
over 20 A be measured. Measurements should only be made in 16A-
fused current circuits or those in which powers greater than 4000 VA
cannot occur. Measurements of currents equal to 20 A must only be
measured for a maximum of 30s duration and must only be performed
at intervals of 15 minutes (cooling down phase for the shunt).
Current
source
DMM
A
Consuming
device,
load, circuit
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