Performing Measurements - Conrad VC444 Bedienungsanleitung

Clockwise, the following measurements are possible:
V = = DC voltage (5 ranges)
V ~ = AC voltage (5 ranges)
hFE = Transistor hFE parameter measurements
->I- = Diode test
A = = DC current (5 ranges "200 µA to 10A")
OHM = Resistance measurements (5 ranges))
g) Data "Hold"
When the "Hold" button in the centre of the rotary switch is pres-
sed, the present measurement indication is 'frozen'. To quit this
subfunction, press the "Hold" button again, after which the measu-
rement is released once more.
h) Display details and operating mode symbols
h1 Diode test
During diode test, the value indicated is the forward voltage
at the test current of approx. 1 mA. The measuring range
here is 0 to approx. 2.0 V.
h2 Negative polarity
When the test leads are reversed or with negative polarity, a
"-" sign appears in front of the measured value.
h3 Transistor test
During the transistor test, the hFE parameter is measured.
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Performing measurements

A DC voltage measurement
The maximum permitted input values of 600 VDC or
VAC rms max. electrically isolated from AC mains in
overvoltage category I or 300 VDC/ACrms max. in
overvoltage category II must not be exceeded un-
der any circumstances.
Do not touch any circuits or circuitry components
when measuring voltages higher than 25 VAC rms
or 35 VDC.
For measurement of DC voltages proceed as follows:
1. Connect the red instrument lead to the V/Ohm socket and the
black instrument lead to the COM socket.
2. Set the required voltage measurement range with the rotary
switch. With DC voltage measurements (V=), 5 measurement
ranges are available: 200 mV, 2000 mV, 20 V, 200 V, 600 V.
3. Connect the test probes to the object to be measured (load, cir-
cuit, etc.).
4. The measured value is shown in the display.
Each of the five DC voltage ranges DCV offers an input resistance
of 10 MOhm. When a "-" appears in front of the DC voltage measu-
red value, the measured voltage is negative (or the test leads are
reversed).
Note!
Because the measuring input is very sensitive, it may be that
with unconnected test leads (not connected to an object to be
measured), meaningless measured values can be displayed.
This "manifestation" is normal and disappears as soon as a
measurement is performed.
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