Urrea UD77, User Manual And Warranty

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E N G L I S H
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in both directions, the device is probably
shorted. If the display reads “
” in both
directions, the device is probably opened.
4.3.1 Diode test.
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
de “VΩ” 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 in good conditions, 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 in good conditions.
NOTE: A detective diode will read (the
overload sign) or 0.00 no matter how the
test leads are connected.
4.3.2 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 diode on. A different
kind of test leads that boost the power
output are needed, so that microwave
diodes can be adequately tested.
4.4 Measuring Current (Amperage).
CAUTION: THE CURRENT FUNCTIONS ARE
PROTECTED BY A 600-VOLT RATED FUSE.
TO AVOID DAMAGE TO THE INSTRUMENT,
CURRENT SOURCES HAVING OPEN CIRCUIT
VOLTAGES GREATER THAN 600 VOLTS DC
OR AC, MUST NOT BE MEASURED.
NOTE: When taking current measurements,
this Meter must be connected in SERIES with
the circuit (or circuit element) under test.
NEVER CONNECT THE TEST LEADS ACROSS
A VOLTAGE SOURCE while the rotary switch
is set to Amps. This may damage the circuit
under test or this Meter.
• To measure current, you must break the
circuit and connect the test leads to two
circuit connection points. The connection
must be in series with the current.
• In alternating current measurement,
waveforms other than sine wave cause
errors.
• When measuring current, the Meter’s
internal shunt resistors develop a voltage
across the meter’s terminals called “burden
voltage”. This voltage drop may affect