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

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32235L
3.2.7 Transistor measurement
To avoid electrical shock and/or damage to the
instrument, before attempting to insert
transistors for testing, always be sure that test
leads have be
en disconnected from any
measurement circuits
．
1. Set the rotary switch to hFE range.
2. Determine whether the transistor to be tested is NPN or
PNP type and locate the Emitter, Base and Collector leads.
3. Insert leads of the transistor into proper holes of the hFE
socket.
4. The meter will show the approx. hFE value at test condition
of base current 10μA and Vce 2.8V.
3.2.8 Current measurement (with clamp, optional)
To avoid electrical shock and/or damage to the
instrument, do not apply more than 250Vdc or
250Vac rms between the terminal and the
COM terminal.
1. Set the rotary switch to the range.
2. Press /~ key to select DCA or ACA measuring mode.
3. Connect the leads of the clamp to the COM and
terminals of the meter.
4. Read the displayed value. The polarity of the V
Ω
terminal
connection will be indicated when making a DCA
measurement.
5. When only the figure“OL " displayed, it indicates overrange
situation.
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3.2.9 Current measurement
To avoid damage to the Meter or injury if the fuse
blows, never attempt an in
-circuit current
measurement where the open-circuit potential to
earth is greater than 250V.
To avoid damage to the meter, check the meter's
fuse before proceeding. Use the proper
terminals, function, and range for your
measurement. Never place the probes in parallel
with a circuit or component when th e leads are
plugged into the current terminals.
The Meter's current ranges are 400.0
µ
A, 4000
µ
A, 40.00mA,
400.0mA, and 10.00A.
To measure current:
1. Turn off power to the circuit. Discharge all high voltage
capacitors.
2. Set the rotary switch to the
µ
A, mA or A range.
3. Press the /
~
key to select DCA or ACA measuring
mode.
4. Connect the black test lead to the COM terminal and the
red test leads to the mA terminal for a maximum of
400mA. For a maximum of 10A, move the redtest lead
to the A terminal.
5. Break the circuit path to be tested.
Touch the black probe to the more negative side of the
break; touch the red probe to the more positive side of
the break. (Reversing the leads will give a negative
reading, but will not damage the Meter.)
6. Turn on power to the circuit; then read the display. Be
sure to note the measurement units at the right side of
the display (
µ
A, mA or A). When only the figure "OL"
displayed, it indicates overrange situation and the higher
range has to be selected.
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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
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