GebraBit TDS Module

OVERVIEW

GebraBit TDS module indicates how many milligrams of soluble solids are dissolved in one liter of water.

TDS (Total Dissolved Solids) indicates how many milligrams of soluble solids are dissolved in one liter of water. In general, the higher the TDS value, the more soluble solids are dissolved in water, and the less clean the water is. Therefore, the TDS value can be used as one reference point for reflecting the cleanliness of water.

This module uses the Definition of resistance: ρ is the resistivity; L is the resistor element’s length; A is a resistor’s cross section. For the conductivity electrode, L is the spacing between two conductive sheets, and A is the area of ​​ the conductive sheet. Definition of conductivity:  According to the above two equations, we can get this equation:  1/R is called conduction G.L/A is called vessel constant Q. The transfer function of the measurement circuit is:   R is the resistance of the electrode when inserted into an aqueous solution. In conclusion, we can get this equation:  Q is the vessel constant. It is constant and different from each electrode. In the schematic, R5 is 820Ω.|Vin| is also a constant depending on the signal generating circuit. Its value is about 200mV. As we can see, the conductivity is linear with the output voltage.

Key Features

• Selectable module power supply voltage between 3V3 and 5V
• On Board, ON/OFF LED indicator
• GEBRABIT Pin Compatible with GEBRABUS
• GEBRABIT small package
• It can be used as a daughter board of GEBRABIT MCU Modules
• Featuring Castellated pad (Assembled as SMD Part)
• Separatable screw parts to reduce the size of the board

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