Megger AVO 830, Руководство пользователя

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Measurements
To Measure Resistance
1. Make sure that:
•
The circuit power is disconnected
•
All high-voltage capacitors are discharged
Note: If a live circuit is detected the instrument will sound a pulsed audible beep and V OL (flashing) shows on
the display.
2. Set-up the instrument as shown in Fig 3.
•
Set the Function Dial to
Ω
•
Red test lead: V terminal
•
Black test lead: COM terminal
3. If manual range is required, press
RANGE
repeatedly to scroll to a suitable range and resolution. Press and
hold
RANGE
to return to AUTO range.
4. Connect the test probe tips to the circuit under test.
The display shows
0L
until a circuit is detected and shows the appropriate resistance when the circuit is detected.
Resistance Measurement Tips
„
The measured value of a resistor in a circuit is often different from the actual value of the resistor
„
Test probes can add 0.1 Ω to 0.2 Ω of error to resistance measurements. To test this resistance, touch the
probe tips together and read the resistance of the test probes. If required, press
REL %
REL
to automatically
subtract this value
„
The resistance function can produce enough voltage to forward-bias silicon diode or transistor junctions,
causing them to conduct. If this is suspected, press
RANGE
to apply a lower current in the next higher
range