User Guide

“SIP” and “CL” will start blinking.

After approximately 50 seconds the instrument

will ask for the HI 93703-10 standard solution

(10 FTU) by displaying “10.0”.

• Fill the cuvette the HI93703-10 standard, insert into the measurement cell and

press the CAL key again.

• After the second calibration point (10 FTU) has

been accepted, the meter will display “500”,

asking for the 500 FTU solution to be placed

in the cuvette holder.

Note: At this point the user can exit the calibration mode and save the two-point

calibration by pressing READ.

• To perform a three-point calibration, place a cuvette filled with HI93703-5

standard solution (500 FTU) in the cuvette holder.

• Press the CAL key. “SIP” and “CL” will start blinking.

• After approximately 30 seconds, the display

will show “----”.

Now the meter is calibrated and ready for use.

Note: If “Err1” is displayed, the calibration data

are maintained

STANDARD SUSPENSION

Hanna Instruments supplies C125 with the AMCO-AEPA-1 standards which has a

long shelf life at all concentrations (approximately six months, if free from

contamination). In addition, no special handling or disposal is required and a much

higher stability of suspended particles has been observed.

On the other hand, the formazine-based standards are very toxic, carcinogen and

unstable (particles flocculate and settle quickly). Lower concentrations change value

within a few days or hours after dilution from stock solutions.

The consistency of C125 readings by using both standards has been separately

established by Advanced Polymer Systems and Hanna Instruments.

Additional documentation about the formazine standard and more complex

calibration procedures is available upon request.