APdt (set Auto Power Down Time)
Press the ^“On/Off” button or the v“pH/mV/Temp” button to select the Automatic Power
Down Time (auto turn off time). The time is programmable over the range of 0 to 250
minutes. Note: if continuous operation is required, select 0to disable the auto turn off
function.
Calibration functions (see also chapter titled “Calibration”).
To enter this mode a special “power up procedure must be followed” this procedure
prevents accidental alteration of calibration and provides a degree of calibration security.
Press the “On/Off” to turn the instrument on.
Press and hold the “Cal/Hold” button whilst the instrument displays 8.8.8.8 during the
wake up cycle. The instrument will momentarily show CAL in the wake up message to let
you know that the calibration level of the function mode is now accessible.
To enter into the calibration mode, you must now enter the function set up mode as
described earlier in this chapter “entering the set up mode” and step through the functions
until the display indicates CAL.
CAL1 &CAL2 (pH calibration using 2 buffer solutions)
Displays and sets the two independent pH calibration points. See "Calibration" chapter for full
details.
UCAL (pH uncalibration).
Used to set the instrument back to the factory calibration values. This function should only
be used when calibration problems exist, and it is necessary to clear the calibration
memory. See "Calibration" chapter for full details.
CAL.E (millivolt calibration).
The millivolt calibration is a single point calibration.
See "Calibration" chapter for full details.
UC.E (millivolt uncalibration).
Used to set the instrument back to the factory calibration values. This function should only
be used when calibration problems exist. See "Calibration" chapter for full details., and it is
necessary to clear the calibration memory.
CAL.t (temperature calibration).
This function is only available if Auto is set to on. The temperature calibration is a single
point calibration. The temperature probe is placed in an accurately known environment
and the correct value is entered into the instrument memory.
UC.t (temperature uncalibration).
This function is only available if Auto is set toon. Used to set the instrument temperature
calibration back to the factory calibration value. This function should only be used when
calibration problems exist, and it is necessary to clear the calibration memory.
Returning to the normal measure Mode
Important; When the calibration is complete, it is advisable to return the instrument to the
normal mode (where calibration functions cannot be tampered with). To return to the
normal mode - turn off the instrument power - wait a few seconds and then restore power.
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