Background to the conductivity sensor and the working principle: The conductivity sensor have two electrodes, through which the fluid passes through and acts as the electrical conductor between the sensor electrodes. The conductivity is measured by applying an alternating electrical current to the sensor electrodes and measuring the resulting voltage.
I am having a conductivity sensor to measure the concentration of fluids passing through it, the fluids passing through it are osmosis water and bicarbonate concentrate, the water is being pumped by a continuous flow pump while the bicarbonate concentrate is being pumped by a rotary vane piston pump, which produces a non-continuous flow. The two fluids pumped through two different tubes are then connected at the end by a T-connector, and then flow through the conductivity sensor. As the flow of the bicarbonate is not continuous, I'm expecting water only to be flowing through the sensor between each two full revolutions of the rotary vane pump, where the conductivity of osmosis water is almost 0 mS/cm while the conductivity of the bicarbonate concentrate is around 2,5. Following my assumption, I am expecting to get a sinusoidal signal with value alternating between 0 and 2,5 but in reality I am getting values between around 1,5 or 2 and 2,5 (mS/cm).
My question is what could be the reason that my sensor is not measuring the 0 values of the osmosis water and instead measures a lower value which doesn't represent the conductivity of water? is my sensor slow? are conductivity sensors in general not suitable for such measurements with such frequent change in its values? I would be thankful if someone could give me tipps how to interpret this behavior.
I am having a conductivity sensor to measure the concentration of fluids passing through it, the fluids passing through it are osmosis water and bicarbonate concentrate, the water is being pumped by a continuous flow pump while the bicarbonate concentrate is being pumped by a rotary vane piston pump, which produces a non-continuous flow. The two fluids pumped through two different tubes are then connected at the end by a T-connector, and then flow through the conductivity sensor. As the flow of the bicarbonate is not continuous, I'm expecting water only to be flowing through the sensor between each two full revolutions of the rotary vane pump, where the conductivity of osmosis water is almost 0 mS/cm while the conductivity of the bicarbonate concentrate is around 2,5. Following my assumption, I am expecting to get a sinusoidal signal with value alternating between 0 and 2,5 but in reality I am getting values between around 1,5 or 2 and 2,5 (mS/cm).
My question is what could be the reason that my sensor is not measuring the 0 values of the osmosis water and instead measures a lower value which doesn't represent the conductivity of water? is my sensor slow? are conductivity sensors in general not suitable for such measurements with such frequent change in its values? I would be thankful if someone could give me tipps how to interpret this behavior.