ENGLISH
35
Notes
If you have no idea of the value of the reading you are taking, start at the highest measurement
position (20A) and the
20A
terminal and then switch progressively to lower ranges until a suitable
reading is obtained.
When AC current measurement has been completed, disconnect the connections between the test
leads and the object being measured.
Measuring resistance
WARNING!
To avoid damage to the instrument or to the object being tested, disconnect all power to the
object and discharge all high-voltage capacitators before measuring resistance.
The resistance measurement ranges are: 200
Ω
, 2k
Ω
, 20k
Ω
, 200k
Ω
, 2M
Ω
, 20M
Ω
and 200 M
Ω
.
To take a resistance reading, connect the instrument as follows:
1.
Connect the red test lead to the terminal
and the black test lead to the
COM
terminal.
2.
Set the mode selector to a suitable measurement range (
Ω
).
3.
Connect the test leads across the object being measured. The reading is shown on the display.
Notes
The test leads can add 0.1 - 0.3 ohm of error to the measurement. To obtain accurate
measurements of small resistances, i.e. in the range of 200
Ω
, short-circuit the input terminals
beforehand and record the reading obtained (call that reading X), which is the extra resistance from
the test leads. Then use the following equation:
Measured resistance (Y) minus (X) = Accuracy value of the resistance
If measuring resistance of >1 M
Ω
, it normally takes a few seconds for the reading to stabilise.
If
"
1
" is displayed, this indicates an open circuit, i.e. no input.
When resistance measurement has been completed, disconnect the connections between the test
leads and the object being measured.
Capacitance measurement
The capacitance measurement ranges are: 2 nF, 20 nF, 2 F and 100 F.
To take a capacitance reading, connect the instrument as follows:
1.
Connect the red test clamp or test lead to the terminal
and the black test clamp or test lead
to the
μ
mA
terminal (UT50A) or the
mA
terminal (UT50B/UT50C).
2.
Set the mode selector to a suitable measurement range (Fcx).
3.
Connect the test leads across the object being measured. The reading is shown on the display.
Notes
To test capacitors with polarity, connect the red test lead to the anode and the black test lead to the
cathode.
If the tested capacitor is short-circuited or the instrument is overloaded, the display will show "
1
".
The test lead or test clamp should be as short as possible to minimise the measurement error
caused by the distributed capacitor.
When the tested capacitance exceeds 30
μ
F, the reading is for reference purposes only.
Resetting to zero can take a while when switching to a different measurement range, but this does
not affect the accuracy of the final readings obtained.
Diode and continuity test
WARNING!
To avoid damage to the instrument or to the object being tested, disconnect all power to the
circuit being tested and discharge all high-voltage capacitators before testing diode and continuity.
Testing diodes
Use this function to test diodes, transistors and other semiconductor 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 and 0.8 volts.
To test a diode out of a circuit, connect the instrument as follows:
1.
Connect the red test lead to the terminal
and the black test lead to the
COM
terminal.
2.
Set the mode selector to
.
3.
To measure a forward voltage drop in a semiconductor component, connect the red test lead to the
component’s anode and the black test lead to the cathode. The reading is shown on the display.
