Urrea UD112, User'S Manual And Warranty Information

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E N G L I S H
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These brief contacts cause the meter to emit
a short beep. This function is convenient for
checking wiring connections and operation
of switches. A continuous beep tone
indicates a complete wire.
CAUTION: USING RESISTANCE AND CONTINUITY
FUNCTION IN A LIVE CIRCUIT WILL PRODUCE FALSE
RESULTS AND MAY DAMAGE THE INSTRUMENT.
IN MANY CASES THE SUSPICIOUS COMPONENTS
MUST BE DISCONNECTED FROM THE CIRCUIT
UNDER TEST TO OBTAIN ACCURATE RESULTS.
Frequency (Hz) Measurements
Frequency is the number of cycles a signal
completes each second. The meter measures
the frequency of a voltage or current signal
by counting the number of times the signal
crosses a threshold level every second.
To measure the frequency of a voltage or
current signal, press the Hz/Duty button
momentarily while measuring voltage or
currents.
The available frequency ranges are:
5 Hz, 50 Hz, 500 Hz, 5 kHz, 50 kHz, 500 kHz,
5 MHz and 10 MHz.
Tips for measuring frequency
• In frequency, the meter is always
autoranging.
• When disconnecting the input terminals,
the overload sign may be displayed or the
display may unsteadily fluctuate. This is
typical.
Duty-Cycle Measurements
Duty-Cycle (or Duty-Factor) is the percentage
of time a signal is above or below a trigger
level during one cycle.
The duty-cycle mode is optimized for
measuring the ON or OFF time of logic and
switching signals. Systems such as electronic
fuel injection systems and switching power
supplies are controlled by pulses of varying
width, which can be checked by measuring
duty-cycle.
Press the Hz/Duty button to toggle between
the Hz mode and the Duty- Cycle mode
when the rotary selector knob is set to Hz
(Duty), , ,
or .
Capacitance Measurements
CAUTION: TO AVOID DAMAGING THE METER
OR THE EQUIPMENT UNDER TEST, REMOVE ALL
POWER FROM THE CIRCUIT AND DISCHARGE
ALL HIGH-VOLTAGE CAPACITORS BEFORE
MEASURING CAPACITANCE. LARGE VALUE
CAPACITORS SHOULD BE DISCHARGED THROUGH
AN APPROPRIATE RESISTANCE LOAD. USE THE
DC VOLTAGE FUNCTION TO CONFIRM THAT THE
CAPACITOR IS DISCHARGED.
Capacitance is the ability of a component to
store an electrical charge.
The unit of capacitance is the farad (F).
Most capacitors are in the nanofarad (nF) to
microfarad (μF) range.
The available capacitance ranges are:
40nF, 400 nF, 4 μF, 40 μF, and 100 μF.
Tips for measuring capacitance
• In capacitance, the Meter is always
autoranging.
• In 40 nF range, the reading are probably
unstable due to environmentally induced