HF scientific CLX Online Residual Chlorine Monitor (Old) - Manual (Page 18)

5.2 Security Access Feature
The instrument is equipped with a security access code feature that can be activated in the
configuration mode. If the security feature is enabled, the screen shown in the illustration
below will appear when the MODE/EXIT button is pressed.
The security code (333) must be entered to gain access to CAL or CONFIG menus.
Notice that the first number in the code is flashing. The flashing indicates that this is the
number to be changed. Use the S or T arrows to select the first of the three numbers in
the code and then press the  button to accept the first number of the code. Now enter the
second number in the code. Proceed as with the first number followed by . Then repeat
the process for the third number in the access code, and finish with the 
button.
If the valid access code has been selected, the instrument will be directed to the calibration
mode. If the wrong access code is selected, the instrument will return to the AUTO mode.
Refer to section 7.5 Enabling the Security Access for more information.
CLX (9/07) Page 12
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