Model Q 1074A - OPERATION MANUAL
4
2. OPERATION
WARNING
1) When measuring voltage ensure that instrument is not connected or switched to resistance range.
Always ensure that the correct terminals are used for the type of measurement to be made.
2) Use extreme care when measuring voltage above 50V, especially from sources where high energy
is existed.
3) Avoid making connections to "live" circuits whenever possible.
4) When making current measurements ensure that the circuit not "live" before opening it in order to
connect the test leads.
5) Before making resistance measurements or diode test, ensure that the circuit under test is
de-energized.
6) Always ensure that the correct function and range is selected. If in doubt about the correct range to
use, start with the highest and work downwards.
7) Extreme care should be taken when using the instrument to conjunction with a current transformer
connected to the terminals if an open circuit occurs.
8) Ensure that the test leads and probes are in good condition with no damage to the insulation.
9) Take care not to exceed the over-load limits as given in the specifications.
10) Before opening the case of the instrument to replace battery or fuse, disconnect the test leads
from any external circuit, set the selector switch to "
OFF
" position.
2.1
Function Press Button
1)
SELECT
(State choice)
There are several functions at one rotary switch position, press
SELECT
button to select function you
want, It allowable to select AC or DC voltage, AC or DC current, Resistance, Diode or Audible
continuity,
℃
or
℉
temperature measurement.
2)
RANGE
(Range selection)
When power on, meter at auto range mode, press RANGE button you can select measurement range
you want. Range is run up with times of pressing RANGE button until its max, then return the min
range. Press RANGE button more than 2 seconds, the meter return to auto range. This button do not
effect on frequency, duty cycle, capacitance, diode & continuity test and temperature measurement.
3)
REL/RS232
(Relative Measurement / RS232 enable)
Press this button the
meter enter relative measuring state and “Δ” symbol appear on LCD. The result
of the relative measurement is the difference between measuring value and reference value. The
reference value is produced same as momentary reading value when pressing this button, press it
again to exit this state and “Δ” symbol disappear on display, and this button do not effect on
frequency, diode and continuity test function. Press this button less than 2 seconds the meter enter
relative measuring state and “Δ” symbol appear on LCD. The secondary function of “REL/RS232”
button is RS232 communication enable and disable. If you press it more than 2 seconds, the RS232
will be started and press it more than 2 seconds again will cancel RS232 communication.
4)
(Data Hold / Backlight)
Press this button less than 2 seconds the meter enter data hold mode and
“HOLD” symbol appear on
LCD, and the momentary value while pressing the button display on LCD. Press it again to exit this
mode and
“ HOLD ” symbol disappear on display. As data hold function, this button do not effect on
diode and continuity test function. The secondary function of
button is backlight enable and
disable. If you press it more than 2 seconds, the backlight will be turn on and press it more than 2
seconds again will make the backlight off.
5)
Hz/DUTY
(Frequency and Duty Cycle measurement switch button)
When you make frequency, AC voltage or AC current measurement, press this button to switch Hz or
duty cycle test mode.
6)
MAX/MIN
(Maximum value / Minimum value)
Press
MAX/MIN
button the meter enter Maximum value / Minimum value record
mode and “ MAX ”
/
” MIN ” symbol appear on LCD, the LCD will display the maximum value or minimum value science
