Resistance Measurement - Mastech MS8268 Instruction Manual

3.2 Measurement 3.2 3.2 3.2 Measurement Measurement Measurement Functions Functions Functions Functions
3.2.1 3.2.1 AC AC and and DC DC Voltage Voltage measurement measurement
3.2.1 AC 3.2.1 AC and and DC DC Voltage Voltage measurement measurement
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750Vac 750Vac rms. rms.
750Vac rms. 750Vac rms.
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the the earth earth ground. ground.
the earth the earth ground. ground.
The polarity of ac (alternating current) voltage varies over
time; the polarity of dc (direct current) voltage is constant.
The Meter's DC voltage ranges are 400.0mV, 4.000V,
40.00V, 400.0V and 1000V; AC voltage ranges are
400.0mV , 4.000V, 40.00V, 400.0V and 750V.
(AC 400.0mV range only exists in manual ranging mode).
To measure ac or dc voltage:
1. Set rotary switch to the DCV or ACV range.
2. Connect the black and red test leads to the COM and
V terminals respectively.
3. Connect the test leads to the circuit being measured
4. Read the displayed value. The polarity of red test lead
connection will be indicated when making a DCV
measurement.
NOTE: NOTE: NOTE: NOTE:
ℕ Unstable display may occur especially at 400mV range,
even though you do not put test leads into input terminals,
in this case, if an erroneous reading is suspected, short
the V terminal and the COM terminal, and make sure the
zero display.
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and/or damage the
take take any take any any any voltage voltage voltage voltage
exceed exceed exceed 1000Vdc 1000Vdc or or or or 1000Vdc 1000Vdc
and/or and/or damage damage to to to to the damage the the
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common terminal common common terminal terminal terminal and and and and
ℕ For better accuracy when measuring the dc offset of an
ac voltage, measure the ac voltage first. Note the ac
voltage range, then manually select a dc voltage range
equal to or higher than the ac range. This improves the
accuracy of the dc measurement by ensuring that the
input protection circuits are not activated.
3.2.2 3.2.2 Resistance Resistance measurement measurement
3.2.2 3.2.2 Resistance

Resistance measurement

measurement
To To To avoid To avoid avoid avoid electrical electrical electrical shock electrical shock shock shock and/or
instrument, instrument, instrument, instrument, disconnect disconnect disconnect disconnect
discharge discharge discharge all discharge all all high-voltage all high-voltage capacitors high-voltage high-voltage
measuring measuring measuring measuring resistance. resistance. resistance. resistance.
The Meter's resistance ranges are 400.0 Ω , 4.000k Ω ,
40.00kΩ, 400.0kΩ, 4.000MΩ and 40.00MΩ.
To measure resistance:
1. Set the rotary switch to Ω Ω Ω Ω 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:
ℕ 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.
ℕ 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.
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circuit circuit circuit circuit power power power power and and and and
capacitors before capacitors capacitors before before before