Velleman DVM 890L User Manual - page 8
DVM890L GB
7
3.7 Diode measurement and Continuity test
1) Connect the black lead (-) to the COM input connector and the red lead (+) to the V/
Ω
/f input
connector.
2) Set the FUNCTION switch to the
/
range and connect the test leads to the diode under
measurement. The display will show the approx. forward voltage of this diode.
3) For continuity tests : connect the test leads to two random points of the circuit. A buzzer will
sound if the resistance is lower than approx. 30
Ω
.
3.8 Transistor hFE test
1) Set the FUNCTION switch to the hFE range.
2) Determine whether the transistor is NPN or PNP and locate the emitter, base and collector leads.
Insert the leads into the proper holes in the socket on the front panel.
3) The display will show the approximate hFE-value at the moment of testing. Base current 10 µA,
Vce 2.8V.
3.9 Temperature measurement
1) Measure temperature with a K-type thermocouple : Set the FUNCTION switch to the T-range
and insert the K-type thermocouple plug into the K-PROBE socket.
2) Measure ambient temperature without a probe : Use the same T-range, the display will show the
ambient temperature in °C.
Note :
1) When measuring temperature with a thermocouple, never touch the cold end (the near end plug)
of the thermocouple with your bare hands as your body temperature will affect the accuracy of
the measurement.
3.10 Auto Power-off
Automatic Power-off extends the battery-life by turning the meter off whenever it has been unused
for the last 15 min. The meter turns back on if either the rotary switch is turned or the power switch
is pressed.