Electro-Chemical Devices (ECD) L20 - Manual (Page 6)

B. Keys
On/Off
Press and hold this key for 5 seconds to power on and
shut off the meter. Once the unit is power up, press the
same key to turn on or off the backlight.
Mode-
Selects display mode. Pressing this key changes the
display sequentially to display pH-AUTO, mV-AUTO, pH
and mV. The calibration values will not be affected by
changing the display modes. In “pH calibration”, press
“Mode” key to exit the two point calibration mode.
Clear-
It is used to clear the unit when error signal appears. It
clears all calibration values stored in the internal
memory.
Under normal use the key will not be activated unless
pressed and held for 2 seconds to prevent accidental
erasing stored memory.
When the Clear key is pressed, all segments of the LCD
will be on. After about 2 seconds the unit will enter the
pH-AUTO mode. The “AUTO” and “CAL” will be on and
one of the buffer values will start to flash. This means
that the unit must be calibrated.
Up/Down-
Increases or decreases the displayed temperature value
when in manual mode, buttons have no effect when in
ATC mode.
Stand/Slope-
The Stand and Slope keys are used for dual or three
point pH calibration of the unit. Pressing and holding
the Stand key while turning on the power, will change
the buffer set to the other available buffer set.
Mea. / Eff.-
The key is used to bring the unit out of the AUTOLOCK
condition when operating in the pH-AUTOLOCK or mV-
AUTOLOCK mode. Press and hold this key for 5 seconds,
the LCD will display the efficiency of the electrode.
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