PeakTech 4120 Bedienungsanleitung Seite 33

Follow these steps to measure AC/DC Voltage:
1. Press DC V or AC V switch.
2. AC appears for AC Voltage measurement.
3. Plug the black probe into the meter's COM terminal and the red probe into the meter's V/Ω terminal.
4. Connect the meter in parallel with the load or circuit.
Notes:
* Polarity is negative, - appears on the left of display.
* To change the measurement range, use R-H UP and DOWN keys.
* For the most accurate measurement, select the lowest voltage range possible without getting an overload
reading.
* Each of the AC/DC voltage ranges presents an input impedance of approximately 10 MΩ in parallel with less than
100 pF. AC voltage is ac-coupled to the 10 MΩ input.
Caution: Never try to measure an AC voltage that is ringing on a DC voltage level where the peak AC voltage
exceeds 500 V with respect to earth ground.
* Your meter will show frequency values in the middle secondary display and dB (m) in the lower secondary display
depending on the input AC Voltage source.
* The value of dB (m) indicates a logarithmic ratio of input voltage to the standard value stored.
Input voltage dB (m)
0,775 mV -60 dB
109 mV -17 dB
1,94 mV 8 dB
19,4 mV 28 dB
* Input impedance: 10 MΩ // 100 pF.
* Frequency Response: 40 Hz to 5 kHz
* The meter´s high input sensitivity produces a wandering effect when the test leads are not connected to any
circuit. This is normal accurate reading will appear when you connect the test leads to a circuit being measured.
Measuring AC/DC current
WARNING: YOU MAY DAMAGE THE METER OR BE INJURED IF THE FUSE BLOWS WHILE CURRENT IS
BEING MEASURED IN A CIRCUIT WHICH EXHIBITS AN OPEN CIRCUIT VOLTAGE GREATER THAN 250 V
DC/AC. THE 20 A TERMINAL IS FUSED. A SERVERE FIRE HAZARD AND SHORT CIRCUIT DANGER EXISTS
IF YOU APPLY A VOLTAGE WITH HIGH CURRENT CAPABILITY TO THIS TERMINAL. THE METER CAN BE
DESTROYED UNDER SUCH CONDITIONS. WHEN USING THIS RANGE WITH HIGH CURRENTS, KEEP THE
DUTY CYCLE TO 30 SECONDS ON LOAD AND 15 MINUTES OFF LOAD.
Follow these steps to measure current:
1. Press DC A or AC A switch.
2. AC appears for AC current measurement.
3. Plug the black probe into your meter's COM terminal and the red probe into your meter's µA, mA or 20 A terminal.
4. To switchover from µA to mA to 20 A, press the DC A or AC A several times.
5. Remove power from the circuit under test and then break the circuit at the appropriate point.
6. Connect the meter in series with the load or circuit under test.
Notes:
* If you do not know approximately what the current is, connect the circuit to 20 A input terminal first to see if you
have a safe level for the mA input terminal. Use the mA input terminal for current up to 400 mA.
* When measuring current, the meter's internal shunt resistors develop a voltage across the meter's terminals
called "burden voltage". This voltage drop is very low in your meter, but, it may affect precision circuits or
measurements.
* If you set the meter for DC current, - appears or disappears to indicate the polarity of the measured current.
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