Grove - TDS Sensor
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 3.⅗V 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.
Feature¶
- Analog Signal, easy to implement
- Support 3.⅗V Input Voltage
- Good Arduino Compatibility, where 0 ~ 2.3V Output Voltage can be easily implemented in 3.⅗V control system
- Waterproof TDS Probe
Specification¶
| Parameter | Value |
|---|---|
| Input voltage | 3.3V / 5V |
| Output Voltage | 0 ~ 2.3V |
| Working Current | 3 ~ 6 mA |
| TDS Measurement Range | 0 ~ 1000ppm |
| Connection Interface | Grove 4-Pin / XHB 2.54mm 2P |
| Interface | Analog |
| Cable Length | 60cm |
| Connection Interface | XHB 2.54mm 2P |
Hardware Overview¶
Platforms Supported¶
| Arduino | Raspberry Pi | |||
|---|---|---|---|---|
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Getting Started¶
Play With Arduino¶
Materials required
| Seeeduino V4.2 | Base Shield | Grove - TDS Sensor |
|---|---|---|
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| Get ONE Now | Get ONE Now | Get ONE Now |
In addition, you can consider our new Seeeduino Lotus M0+, which is equivalent to the combination of Seeeduino V4.2 and Baseshield.
Hardware Connection¶
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Step 1. Plug Grove - TDS Sensor to A0 port of Grove - Base Shield.
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Step 2. Plug Grove - Base Shield into Seeeduino.
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Step 3. Connect Seeeduino to a PC via a USB cable.
Software¶
Attention
If this is the first time you work with Arduino, we strongly recommend you to see Getting Started with Arduino before the start.
- Step 1. Open the Arduino IDE and create a new file, then copy the following code into the new file.
#define SERIAL Serial
#define sensorPin A0
int sensorValue = 0;
float tdsValue = 0;
float Voltage = 0;
void setup() {
SERIAL.begin(9600);
}
void loop() {
sensorValue = analogRead(sensorPin);
Voltage = sensorValue*5/1024.0; //Convert analog reading to Voltage
tdsValue=(133.42/Voltage*Voltage*Voltage - 255.86*Voltage*Voltage + 857.39*Voltage)*0.5; //Convert voltage value to TDS value
SERIAL.print("TDS Value = ");
SERIAL.print(tdsValue);
SERIAL.println(" ppm");
delay(1000);
}
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Step 3. Upload the demo. If you do not know how to upload the code, please check How to upload code.
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Step 4. Open the Serial Monitor of Arduino IDE by click Tool-> Serial Monitor. Or tap the Ctrl+Shift+M key at the same time. Set the baud rate to 9600.
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Step 5. The result should be like this when the probe is in water:
Play With Raspberry Pi¶
Materials required
| Raspberry Pi | Grove Base Hat for RasPi | Grove - TDS Sensor |
|---|---|---|
 |
 |
|
| Get ONE Now | Get ONE Now | Get ONE Now |
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Step 2. Plug the Grove Base Hat into Raspberry Pi.
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Step 3. Connect the Grove - TDS sensor to port A0 of the Base Hat.
- Step 4. Connect the Raspberry Pi to PC through USB cable.
Software¶
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Step 1. Follow Setting Software to configure the development environment.
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Step 2. Download the source file by cloning the grove python library.
cd ~
git clone https://github.com/Seeed-Studio/grove.py
- Step 3. Execute below commands to create the python code.
cd grove.py/grove/
nano TDS.py
- Step 4. Copy the following code into the file:
import math
import sys
import time
from grove.adc import ADC
class GroveTDS:
def __init__(self, channel):
self.channel = channel
self.adc = ADC()
@property
def TDS(self):
value = self.adc.read(self.channel)
if value != 0:
voltage = value*5/1024.0
tdsValue = (133.42/voltage*voltage*voltage-255.86*voltage*voltage+857.39*voltage)*0.5
return tdsValue
else:
return 0
Grove = GroveTDS
def main():
if len(sys.argv) < 2:
print('Usage: {} adc_channel'.format(sys.argv[0]))
sys.exit(1)
sensor = GroveTDS(int(sys.argv[1]))
print('Detecting TDS...')
while True:
print('TDS Value: {0}'.format(sensor.TDS))
time.sleep(1)
if __name__ == '__main__':
main()
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Step 5. Use Ctrl+O to save and Ctrl+X to quit.
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Step 6. Run the following to execute:
python TDS.py 0
Success
If everything goes well, you will be able to see the following result:
pi@raspberrypi:~/grove.py/grove$ python TDS.py 0
Detecting TDS...
TDS Value: 0
TDS Value: 0
TDS Value: 0
TDS Value: 0
TDS Value: 2.41591963768
TDS Value: 28.5884239197
TDS Value: 33.2677587509
TDS Value: 30.9311414242
TDS Value: 30.9311414242
FAQ¶
Q1# Limitations of Grove - TDS Sensor/Meter For Water Quality (Total Dissolved Solids)?
A1: Limitations are as followed:
- The Waterproof TDS probe cannot be used in water above 70°C.
- The sensor cannot be used to measure flowing water.
- The sensor cannot be used to measure water with high pollution concentration.
- The Grove sensor itself is not waterproof.
