How To Make Measurements - Conrad MXD 4660 A Bedienungsanleitung

Set the upper limit value in the same manner (with polarity and the five-digit measure-
ment value). After completing entry of your comparison/limit values, repress the
SET/R button. When you have completed setting the measurement range (as far as
manually possible) the comparison measurement (CMP) becomes active.
To quit this function, briefly press or the "FUNC" button. Resetting via the SET/R but-
ton is also possible, even during the measurement.
g) Details of display and display codes for operating modes
g 1 Diode test and continuity check
The value displayed in the diode test is the conducting state voltage at approx. 1 mA
test current. The measurement range in this case is 0 to approx. 2.0 V. The continui-
ty check allows you to check continuity for dead cables, plug-in connectors or fuses
both acoustically and optically (display of the measurement value, but in mV). A beep
is given with resistances smaller than 30 W.
g 2 Negative polarity
If measuring leads have been unintentionally reversed, or with negative polarity, a
minus sign (-) is displayed in front of the measurement value.
g 3 FREQ Frequency measurement
This function allows frequency measurements up to 20 MHz
g 4 hFE Transistor test
The transistor test measures the hfe parameter
g 5 rDY ( = ready) = logic test
This function allows you to measure and display all standard logic levels
g 6 All other codes representing various units of measurement:
AC= AC parameter (DC = DC parameter)
mV = millivolt (exp.-3)
V = volt
mA = milliampere (exp.-3)
A = ampere
Hz = hertz
kHz = kilohertz (exp.3)
MHz = megahertz (exp.6)
kW = kiloohm (exp.3)
MW = megaohm (exp.6)
dB = decibel
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How to make measurements

A Measuring voltage
Important!
Never exceed the max. permissible input parameters (1000 VDC
max. or 750 VAC rms max.).
Do not touch circuits or circuit components if the voltage you
measure in them is greater than 25 VACrms or 35 VDC.
This is how you measure DC or AC voltages:
1. Connect the red measuring lead to the V/Ohm socket, and the black
measuring lead to the COM socket.
2. In the button cluster "RANGE", set the voltage range required. For DC or True
RMS AC voltage measurements, there are five measurement ranges (200 mV-2-
20-200-2000) for both AC and DC for you to choose from.
Important!
The button "2000" is only permitted for voltage measurements up
to 1000 VDC (or 750 VACrms max.).
In AC voltage measurements, the middle subdisplay also shows frequency and the
lower subdisplay shows a decibel value for the AC voltage measured. To measure
DC voltage, you must observe the following points!
3. Connect the measuring leads to the object under test (load circuit, etc.).
4. The polarity of each measurement value is shown alongside the current measu-
rement value in the main display.
Each of the DC voltage ranges (as well as each of the AC voltage ranges) has an
input resistance of 10 MÍ. (in the AC voltage range parallel to < 20 pF (AC-coupled).
If a minus sign (-) is shown in front of the measurement value, the voltage measured
is negative (or the measuring leads have been inadvertently switched).
Important!
The measurement input is very sensitive. For this reason, the devi-
ce may display measurement values even when the measuring
leads are not connected to a test object. This phenomenon is nor-
mal and stops as soon as you make a measurement. However,
during these "phantom" measurement values, the Auto-Power-Off
function is disabled (for AC voltages "mV" and "V").
During DC voltage measurement, the three subdisplays located to
the right of the main display are also active. The upper subdisplay
displays the current measurement value with a 1 s delay. The
middle display shows the measurement value with a 2 s delay. The
lower subdisplay shows the measurement value with a 3 s delay.
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