Velleman DVM630 Mode D'emploi page 11

current to be measured is unknown beforehand, connect the red test
lead to the "10A" socket and set the range switch in the highest range
position. Then reduce gradually until the ideal resolution is obtained.
5. Break the circuit path to be tested.
6. Connect the black test probe to the more negative side of the break;
connect the red test probe to the more positive side of the break
(connection in series). Reversing the probes will give a negative
reading, but will not damage the meter.
7. Switch on the power supply of the circuit to measure.
The measured value appears on the display. For DC measurements,
when a negative polarity is present at the red test probe, the indicated
value is preceded by a "–" sign. When the measured value is higher
than the selected range limit, the display shows "1". Select a higher
range.
8. Cut off the power supply of the circuit to measure.
9. Discharge all the high-voltage capacitors.
10. Remove the test probes from the circuit.
11. Restore the circuit to its original condition.
7.6 Measuring Resistance
To avoid electrical shock and/or damage to the instrument,
disconnect the circuit power and discharge all high-voltage capacitors
before measuring resistance.
Never perform resistance measurements on a live circuit.
The meter‟s ranges are: 200.0Ω, 2.000 kΩ, 20.00 kΩ, 200.0 kΩ, 2.000 MΩ.
To measure resistance:
1. Select the appropriate " " range with the rotary switch.
2. Connect the black test lead to the "COM" socket and the red test lead to
the "VΩmAhFE" socket.
3. Connect the test probes to the circuit/component under test.
The measured value appears on the display.
Notes:
The measured value of a resistor in a circuit often differs from the
resistor‟s rated value. This is because the meter‟s test current flows
through all possible paths between the probe tips.
To increase accuracy when measuring low resistance values, first hold
the tips of the test probes together to determine the resistance value of
the test leads. Subtract this value from the measured value of the
circuit.
If the measured resistance exceeds the selected range or in case of an
open circuit, the display shows "1".
V. 01 – 22/04/2013
DVM630
11 ©Velleman Inc.