Diode Test; Continuity Check - Forch F73 Bedienungsanleitung

To measure resistance:
1. Set the rotary switch to
2. Connect the black and red test leads to the COM and Ω terminals respectively.
3. Connect the test leads to the circuit being measured and read the displayed value.
Some tips for measuring resistance:
The measured value of a resistor in a circuit is often different from the resistor's rated
value. This is because the Meter's test current flows through all possible paths between
the probe tips.
In order to ensure the best accuracy in measurement of low resistance, short the test
leads before measurement and memory the test probe resistance in mind. This neces-
sary to subtract for the resistance of the test leads.
On 40 MΩ range, the meter may take a few seconds to stabilize reading. This is normal
for high resistance measuring.
When the input is not connected, i.e. at open circuit, the figure "OL" will be displayed for
the overrange condition.

3.2.3 Diode Test

To avoid electrical shock and/or damage to the instrument, disconnect circuit power
and discharge all high-voltage capacitors before testing diodes.
Use the diode test to check diodes, and other semi- conductor devices. The diode test
sends a current through the semiconductor junction, and then measures the voltage drop
across the junction; a good silicon junction drops between 0.5 V and 0.8 V.
To test a diode out of a circuit:
1. Set the rotary switch to
2. Press the FUNC key one time to ativate Diode Test.
3. Connect the black and red test leads to the COM and
4. For forward-bias readings on any semiconductor component, place the red test lead on
the component's anode and place the black test lead on the component's cathode.
5. The meter will show the approx. forward voltage of the diode. If the test lead connection
is reversed, only figure "OL" displayed.
In a circuit, a good diode should still produce a forward bias reading of 0.5 V to 0.8 V;
however, the reverse-bias reading can vary depending on the resistance of other pathways
between the probe tips.

3.2.4 Continuity Check

To avoid electrical shock and/or damage to the instrument, disconnect circuit power
and discharge all high-voltage capacitors before testing for Continuity.
Continuity is a complete path for current flow.
The beeper sounds if a circuit is complete. These brief contacts cause the Meter to emit
a short beep.
To test for continuity:
1. Set the rotary switch to
2. Press the FUNC key twice to activate Continuity Check.
3. Connect the black and red test leads to the COM and Ω terminals respectively.
4. Connect the test leads to the resistance in the circuit being measured.
5. When the test lead to the circuit is below approx. 60 Ω, a continuous beeping will indi-
cate it.
Note:
Continuity test is available to check open/short of the circuit.
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terminals respectively.