Urrea UD85, Руководство пользователя и гарантия

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E N G L I S H
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4.3 Continuity test, diode test and
microwave diodes
4.3.1 Continuity test
This mode helps you check electrical
circuits, such as wiring, speaker cables,
connections, switchers, or relays for
short or open circuits. In continuity test,
a measured value approx. 100 Ω or less
causes the Meter to emit a continuous tone.
Follow these steps to check continuity:
1. Set the function switch to the “ ”
position.
2. Insert the black test lead into the “COM”
input terminal and the red test lead into
the “VΩHz CAP” input terminal.
3. Connect the test leads to the circuit to be
measured.
4. This Meter will emit a continuous tone for
resistance of less than 100 ohms.
4.3.2 Diode test
Diode test lets you check diodes, transistors,
and other semiconductors for opens, shorts
and normal operation. NEVER CONNECT
THE TEST LEADS TO A SOURCE OF VOLTAGE
when the rotary switch is set to
.
In diode test, drop voltage in the forward
direction in displayed when diode is
connected in the forward direction. For
a germanium diode, the typical forward
voltage is about 0.4V and in case of a silicon
diode, about 0.6V.
Judge the semiconductor device as
follows:
• If the digital reading in one direction
shows a value and the reading in reverse
direction shows
an overload , the
device is good.
• If the digital reading is the same in both
directions, the device is probably shorted.
• If the display reads in both
directions, the device is probably open.
Follow these steps to check a diode:
1. Set the function switch to the position.
2. Insert the black test lead into the “COM”
input terminal and the red test lead into the
“VΩHz CAP” input terminal.
3. Touch the red test lead to the Anode (+
side, non-banded end) and the black test
lead to the Cathode (- side, banded end).
4. If the diode is good, the reading should
indicate 0.3V to 0.8V on the LCD.
5. Reverse the red and black leads on the
diode, if the LCD reads
(the overload
sign), the diode is good.
NOTE: A detective diode will read
(the overload sign) or 0.00 no matter how
the test leads are connected.
4.3.3 Microwave diodes.
Most microwave diodes can not be tested by
a DMM with a diode test function. This is
because the DMM does not supply enough
power to turn these diodes on. A special
kind of test leads, that boosts the power
output so that microwave diodes can be
adequately tested are needed.
4.4 Measuring current (Amps).