Inrush Measurement; Back-Light And Clamp Lighting; Automatic Shutdown; Measurement Preparation - Mastech MS2225A Operation Manual

4.10 ▲function
Short-press in the harmonic measurement interface at
KW and W gears to scroll up, and to switch between the
1st harmonic and 20th harmonic. At the KW and W gears,
short-press the function key in the maximum/minimum
value measurement interface to scroll up, and switch and
display the maximum/minimum value.

4.11 INRUSH measurement

Long-press "Hz/%/INRUSH/▲" for more than 2 s at AC
current gear to enterthe inrush measurement state.

4.12 Back-light and clamp lighting

1) During measurement, if the ambient light is too dim to
read, press the "B.L/HOLD" for more than 2 s to turn on
the back-light, and the back-light will be off 20 s later.
2) In this period, press the "B.L/HOLD" key for 2 s to turn
off the back-light.
3) Turn on the back-light of the meter at the current gear,
and the clamp lamp will be on at the same time.
The luminous object of the back-light is LED with high
working current.
Although this meter is set with timing circuit (with time
of 30 s), the service life of battery will be shortened
with frequent use of back-light.
Therefore, you shall minimize the use of back-light as
far as possible under the unnecessary conditions.
Note:
When the battery voltage ≤ 7.2 V, the display will display
the symbol of " "(under-voltage). However,
if the back-light is used, when the battery voltage ≥ 7.2 V,
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the battery voltage is reduced due to high working current,
the display may display the symbol "
symbol of " " is displayed, the measurement accuracy
cannot be guaranteed). Under such circumstance, the
battery will not be replaced until the symbol "
displayed without back-light.

4.13 Automatic shutdown

1) After startup, in case of no operation within 30 minutes,
the meter will enter the dormant state and shut down



automatically for saving electric energy. There will be




voice prompt (a prolonged blast) from the buzzer 1




minute before shutdown, and then the meter will shut




down automatically.
2) After shutdown, press FUNC key and the meter will




resume operation.
3) If the "B.L/HOLD" key is pressed during startup, the




function of automatic shutdown will cancel automatically.

4.14. Measurement preparation

1) Turn the change-over switch to power on the meter. If
the battery is in under-voltage state (the voltage ≤ 7.2 V),
the display will display the symbol "
battery shall be replaced.
2) " " means that the input voltage or current shall not
be greater than the indicated value in order to prevent




the internal circuit from damage.
3) Turn the change-over switch to the required




measurement function and range.
4) For wiring, connect the public testing line at first and




then connect the energized testing line. For




disconnecting,
remove the energized testing line at first.
"(when the
" is
", and then the
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