Diode Testing - Clas Ohlson UNI-T UT131B Bedienungsanleitung

Diode testing

1. Connect the black test lead
to COM and the red lead
to VmAµA.
2. Set the function selector
switch to and press
[ HOLD/SEL ] to measure
the threshold value (V) of
diodes.
3. Connect the black test
lead to the cathode and
red test lead to the anode
of the diode to be
tested. Read the forward
voltage drop value from
the display. If " " appears
on the display, reverse
the polarity of the diode
connections.If that doesn't
help, the diode may be
faulty.
Warning:
Make sure that the circuit to be tested is not energised before you begin
to test diodes. Be extremely cautious when using this instrument on
an inductive component such as a transformer, relay coil and the like,
and make sure it has been discharged beforehand. High voltage may be
induced at the measuring points when the circuit is broken.
Note: A good diode should have a forward voltage drop ranging from
0.5 to 0.8 V. However, the reverse voltage drop reading can vary a lot
depending on the resistance of other paths of conductance between
the tips of the test leads.
UT131B
HOLD/SEL
OFF
20M
200m
200k 2000m
20k
20
V
2000
200
200
250
250
V
200
200
200m
1.5V
10 9V
12V
FUSED FUSED
250V Max 200mA Max
10 sec Max CAT II 250V
9