Mastech MS2025A, Operation Manual

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- Forward DC current is about 1mA
- Backward DC voltage is about 3.3V
- Overload protection: 250V DC or AC (RMS)
1) In the process of measurement, if reading hold is
required, press
“
HOLD/B.L
” key, the value on the
display will be locked. Press “
HOLD/B.L
” key again to
cancel reading hold state.
4. Operating Guidance
4.1 Reading Hold
4.2 Manual Measuring Range
RANGE key is automatic/manual measuring range key to
trigger mode. The preset one is automatic measuring
range. Press to switch to manual measuring range. In the
manual measuring range mode, click once to change to
upper range. Continue to the top range, then continue to
press this key to change to the bottom range, followed by
recycling. If this key is pressed more than 2 sec, it will
switch back to automatic measuring range state.
In capacitance and frequency measurement state, rhw
manual measuring range button is invalid.
Note:
4.3 Frequency/Duty Ratio Switch
1) When the meter is in AC voltage mode, if “Hz/%” button
is pressed, the meter will measure Hz, and measure AC
voltage, AC current signal frequency. Click
“Hz/%”
button again, the meter will measure DUTY cycle, and
measure voltage and current signal duty ratio. If it is in
HZ/DUTY position, pressing
HZ % key will switch
between HZ and DUTY by recycling.
2) If
“Hz/%” button is pressed again, the meter will revert
to voltage, current measurement state.
Note:
The meter is in the maximum/minimum value
measurement state, it can't switch to frequency, duty
ratio measurement mode.