Performing Measurements - Conrad VC-222 Bedienungsanleitung

h) Display details and operating mode symbols
- Diode test
The value which is displayed during the diode test is the voltage
conducted at the approx. 1 mA test current. The measuring
range here is 0 to approx. 3.0 V.
- Negative polarity
When the test leads are reversed or with negative polarity, a "-"
sign appears in front of the measured value.
- Transistor test
During transistor test, the hFE parameter is measured "ß"
- All remaining symbols indicate the various units of measure-
ment:
AC = AC value
mV = millivolt (exp.-3)
V = Volt
uA = microampere (exp.-6)
mA = milliampere (exp.-3)
A = ampere
ß = hFE value when measuring transistors
k½ = kiloohm (exp.3)
M½ = megohm (exp.6)
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Performing measurements

A Direct voltage measurement
The maximum permitted input value, 600 V DC or V
AC rms max., must not be exceeded under any
circumstances.
Do not touch any circuits or circuitry components
when measuring voltages higher than 25 V AC rms
or 35 V DC.
For measurement of DC voltages 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 to "V="; range-switching occurs auto-
matically, i.e. the measuring instrument matches itself automati-
cally to the measured value.
3. Connect the test probes to the object to be measured (load,
circuit, etc.).
4. The respective polarity of the measured value is shown in the
display, together with the present measured value.
Each of the five DC voltage ranges DCV offers an input resistance
of 10 MOhm; in the 400 mV range this rises to more than 4 GOhm
(4000 MOhm). The AC voltage ranges have an input impedance of
10 MOhm min. in parallel with < 20 pF (AC-coupled).
When "-" appears in front of the DC voltage measured value, the
measured voltage is negative (or the test leads are reversed).
Notes!
Because the measurement input is very sensitive, it may be
that with unconnected test leads (not connected with a test
circuit) random measured values may be displayed. This "ma-
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