SW Stahl PROFI Tools 32235L, Operator'S Instruction Manual

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32235L
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 range.
2. Press the / key 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 50 Ω , a
continuous beeping will indicate it.
Note:
∞
Continuity test is available to check open/short of the
circuit.
3.2.5 Capacitance measurement
To avoid electrical shock and/or damage to the
instrument, disconnect circuit power and
discharge all high-voltage capacitors before
measuring capacitance. Use the dc voltage
function to confirm that the capacitor is
discharged.
Capacitance is the ability of a component to store an
electrical charge.
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The unit of capacitance is the farad (F). Most capacitors are
in the nanofarad to microfarad range. The Meter measures
capacitance by charging the capacitor with a known current
for a known period of time, measuring the resulting voltage,
then calculating the capacitance. The measurement takes
about 1 second per range.
The Meter's capacitance ranges are 4.000nF 40.00nF,
400.0nF, 4.000
µ
F, 40.00
µ
F and 200.0
µ
F.
To measure capacitance:
1. Set the rotary switch to
Cap range.
2. Connect the black and red test leads to the
COM
and
Cx
terminals respectively.
3. Connect the test leads to the capacitor being measured
and read the displayed value.
Some tips for measuring capacitance:
Ω
The meter may take a few seconds (200 F range, 30
seconds) to stabilize reading. This is normal for high
capacitance measuring.
To improve the accuracy of measurements less than 4nF,
subtract the residual capacitance of the Meter and leads.
3.2.6 Frequency measurement
Do not measure Frequency on high voltage
(>250V) to avoid electrical shock hazard and/or
damage to the instrument.
1. Set the rotary switch to
Hz
range.
2. Connect the black and red test leads to the COM and Hz
terminals respectively.
3. Connect the test leads across the source or load under
measurement, and read the displayed value.
Note:
Ω In noisy environment, it is preferable to use shield cable for
measuring small signal.
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Ω
15
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, transistors, and other
semiconductor devices. The diode test sends a current
through the semiconductor junction, then measures the
voltage drop across the junction, A good silicon junction
drops between 0.5V and 0.8V.
To test a diode out of a circuit:
1. Set the rotary switch to range.
2. Press the
/
key to activate Diode Test.
3. Connect the black and red test leads to the COM and
V terminals respectively.
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.
In a circuit, a good diode should still produce a forward bias
reading of 0.5V to 0.8V; however, the reverse-bias reading
can vary depending on the resistance of other pathways
between the probe tips.
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Ω
The Meter's resistance ranges are 400.0 Ω, 4.000kΩ,
40.00kΩ, 400.0kΩ, 4.000MΩ and 40.00MΩ.
To measure resistance:
1. Set the rotary switch toΩ range.
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 necessary to
subtract for the resistance of the test leads.
∞ The resistance function can produce enough voltage to
forward-bias silicon diode or transistor junctions, causing
them to conduct. To avoid this, do not use the 40MΩ range
for in-circuit resistance measurements.
∞ On 40MΩ 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.
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