Resistance Measuring; Diode Test - VOLTCRAFT VC175 Bedienungsanleitung

c) Resistance measuring
Make sure that all the circuit parts, switches and components and other objects of
measurement are disconnected from the voltage and discharged.
Proceed as follows to measure the resistance:
1. Turn the DMM on and select measuring range "Ω".
2. Insert the red measuring lead into the Ω socket (8) and the black measuring lead into the COM
socket (9).
3. Check the measuring leads for continuity by connecting both measuring leads to one another. After
that the resistance value must be approximately 0.5 Ω (inherent resistance of the measuring leads).
4. Now connect the measuring prods to the object to be measured. As long as the object to be
measured is not high-resistive or interrupted, the measured value will be indicated on the display.
Wait until the display has stabilised. With resistances of >1 MΩ, this may take a few seconds.
5. As soon as "OL" appears on the display, you have exceeded the measuring range or the measuring
circuit has been broken. Select a larger measuring range if necessary.
6. After measuring, remove the measuring leads from the measuring object and turn the DMM off.
Turn the rotary switch (5) to the position "OFF".
If you carry out a resistance measurement, make sure that the measuring points which you
contact with the measuring prods are free from dirt, oil, solderable lacquer or similar. An
incorrect measurement may result under such circumstances.
d) Diode test
Make sure that all the circuit parts, switches and components and other objects of
measurement are disconnected from the voltage and discharged.
1. Turn the DMM on and select measuring range "Ω".
2. Press the SELECT button (1) until
3. Insert the red measuring lead into the
socket (9).
4. Check the measuring leads for continuity by connecting both measuring prods to one another. After
that the value must be approximately 0 V. An acoustic signal can be heard.
5. Now connect the two measuring prods with the object to be measured (diode).
6. The display shows the continuity voltage in volt (V). Open-circuit voltage is about 1.5 V.
7. If "OL" is shown, the diode is measured in reverse direction or the diode is faulty (interruption).
Perform a counter-pole measuring for control reasons. The red measuring lead corresponds to the
positive pole (anode), the black measuring lead to the negative pole (cathode). A silicone diode has
an on-state voltage of approx. 0.5 – 0.8 V.
34
shows on the LC display (4).
socket (8) and the black measuring lead into the COM