SEFRAM 99 Manuel D'utilisation page 29

(4) Diode Measurement
Diode measurement mode shares the same
configuration with 4000V manual voltage measurement
mode.
If the test circuit is open or the voltage drop between the
two ports of the device (diode) under test are larger than
2V, the LCD will show "OL".
The buzzer generates a 2kHz sound whenever the digit
number is less than 0.25V. Because the cycle time of
measurement is only 50ms, the least significant digit will
not display.
1 2 3 4 5 6 7 8 GND
OFF
V
Ω
OFF
DMM
AutoRanging
CAT III
600V
- -
12
Diode