Resistance Measurement - Conrad Electronic VC - 200 Green DMM Anleitung

Attention!
Never measure currents in circuits in which voltages over 250
VDC/VAC could exist, this is life dangerous! Never measure
currents exceeding 20 A. Only measure in circuits which are
fused with 16A or in which powers exceeding 4000 VA could not
exist.
Current measurements of 20 A may not last more than 30 sec.
and may only be executed in intervalls of 15 minutes.
measuring unit
A
voltage source
–
Figure Current Measurement
5.4 Diode Test and Continuity Check
a) Continuity Check " ":
With this function you can check dead leads, fuses, circuits.
Proceed as follows:
Switch on your measuring unit. Set the rotary function switch to "
". Afterwards connect the test-lead tips with the object to be
measured. If the line resistance is less than 100 Ohm an acoustic
signal is emitted.
Attention!
Never measure capacitors which carry voltage, as a possible
discharge could destroy your measuring unit.
15
measured object
b) Diode Test
Switch on your measuring unit. Set the rotary function switch (9) to
" ". Now connect the test-lead tips with the object to be measured,
a dead semiconductor line, the red test-lead tip to the anode, the
black test lead tip to the cathode (as a rule it is marked with a coloured
ring, point etc. )
If you check a diode line in forward direction, you will measure a
voltage from approx. 0.25 V (Germanium) or from 0.7 V (Silicium) to 1 V,
if the diode line is not defective.
If you now exchange the test-lead points, this means red to the
cathode and black to the anode, you check the so called reverse
direction. If "1" or "-1" is displayed the diode is o.k. However, if a value
between 0 V and approx. 3 V is displayed, you connected the object
under measurement wrong or it is defective.
Attention!
During diode test pay attention that the diode or the circuit in
which it is build in is without voltage. All existing capacities
must be discharged.

5.5 Resistance Measurement

Attention!
Make shure all objects, circuits and components to be measured
are without voltage!
Set the rotary function switch to resistance measurement "Ω" (=Ohm).
Now connect the test lead tips with the object to be measured.
During resistance test, make shure that the measuring points, which
touch the test-lead tips are free of dirt, oil or solder varnish etc. This
might influence the measuring value.
16