Preparing the Dissolved Oxygen Level Sensor Probe:

For a new dissolved oxygen probe, first thing to remember begin by adding 7.5% KCL solution into the membrane cap as the filling solution. Follow these steps:

1. Remove the membrane crown.
2. Place the DO membrane on the cap and fix the crown to the electrolyte tube, covering one side of the membrane.
3. Ensure the membrane has no wrinkles and is not punctured or damaged.
4. Unscrew the membrane cap from the probe and fill about 2/3 volume of the cap with KCL solution.
5. Keep the probe in a vertical position concerning the horizontal plane.
6. Carefully screw the cap back onto the probe. Some solution overflow is acceptable to ensure the probe is fully filled with KCL solution, eliminating air bubbles.
7. The 7.5% KCL solution acts as a suitable electrolyte in the DO Probe.
8. The electrode tube should be free of air bubbles to prevent fluctuations in readings.

The turbidity sensor module converts the current signal output by the sensor into a voltage signal and performs AD conversion data processing through the single-chip microcomputer. The remodelling module has analogue and digital output interfaces. The analogue quantity can be sampled and processed by the single-chip A/D converter to know the current water pollution. The digital value can be adjusted through the potentiometer on the module to adjust the trigger threshold. When the turbidity reaches the set threshold, the D1 indicator will be lit, the output of the sensor module changes from high level to low level, and the single-chip monitors the change in level To determine whether the turbidity of the water exceeds the standard, so as to warn or link other equipment. The module is inexpensive, easy to use, and has a high measurement accuracy

It can be used to measure the degree of water pollution of products such as washing machines and dishwashers; it can also be used in industrial field control, environmental sewage collection and other occasions that require turbidity detection and control.

This is a SeeedStudio Grove TDS Sensor/Meter For Water Quality.

The Grove – TDS Sensor detects the Total Dissolved Solids (TDS) levels in the water which can be used to indicate the water quality. The Grove – TDS Sensor can be applied in water quality applications such as TDS meter, well water, aquarium, hydroponics, etc.

It supports 3.3/5V input voltage and 0 ~ 2.3V Output Voltage making it easy to be compatible with all Arduino Boards. The sensor also provides a waterproof probe, making the testing process much easier to handle.