1. Wiring
1.1 CM44x Power Wiring
2 CM44x and Sensor Wiring
3 Settings
, since there is no difference in appearance between CM444, CM448 and CM442, only the number of transmitter channels in the instrument is different, now we take CM442 as an example, simply say the key of the instrument, and the display interface of the instrument after power on. As can be seen in the figure below, there are 4 buttons and a knob. The knob can be adjusted left and right. The middle of the knob is the OK key. Press the OK key to enter the system menu.
3.2 to set the range Select the correct data source and measurement value under the "Menu/Settings/Output Settings/Current Output x: x" menu, and set the range low value and the range high value.
3.2 measurement compensation settings Turn on the compensation under the "Menu/Settings/Input/CHx:x:x ISE/Ammonia/Compensation" menu, and set the compensation type to pH and potassium ion. The selectivity factor does not need to be changed.
3.3 air and purge settings
to bind the cleaning with the cleaning program under the menu "Menu/Settings/Input/CHx:x:X ISE/Extended Settings", then set the cleaning cycle and cleaning time for the cleaning program under the menu "Menu/Settings/Additional Functions/Cleaning", and then start the cycle normally and automatically.
3.4 transmitter reset and sensor reset
selecting "Factory Default" under the "Menu/Diagnostics/Reset" menu. Select "Factory default measurement processing" under the "Menu/Settings/Input/CHx:x:X ISE/Extended Settings" menu to reset the sensor.
4 Calibration
For ISE sensors, the pH electrode and the ISE electrode need to be calibrated separately. Use the pH standard solution and select pH under the menu "Menu/Calibration/ISE/Two-Point Calibration" to perform calibration. Take 2L of on-site water samples and obtain the assay values of the water samples in the laboratory. Add ammonia/nitrate ammonia standard solution provided by 1mL E H into the water sample, and the actual reference value of the water sample should be: laboratory test value 7mg/L. Select ammonia/nitrate nitrogen under the menu of "Menu/Calibration/ISE/Single Point Calibration", enter the reference value, and perform single point calibration.
5 Maintenance
According to the pollution situation on site, the sensor is cleaned regularly. ISE electrode (including ammonia, nitric nitrogen and potassium ion) is coated with cap every six months, and electrolyte is replaced. pH reference electrode and chloride ion electrode coated with cap are replaced every year. Calibrate the electrodes as necessary according to the site conditions. The detailed maintenance cycle is shown in the table below.
electrode maintenance package includes: 2 ammonia cartridges/nitroammonia and potassium ion electrode coated caps, 1 chloride ion electrode coated cap, and a bottle of electrolyte. The method of replacing ISE electrode coated and electrolyte is as follows:
note that the ISE electrode maintenance package will contain a calibration certificate corresponding to the coating. When the coating is replaced, the slope on the calibration certificate must be entered into the transmitter calibration information menu, and then a little calibration must be carried out.
input slope method is as follows:
