Grove GSR sensor v1.2 cannot adjust resistor to 512


I just bought one a GSR sensor, and tried to adjust the resistor to serial output 512 but i cannot seem to do so. It keeps fluctuating wildly between ~800 to ~100, and no matter how slowly i turn it, it always goes from 100 to 800. I have attached the readings and the code I used. Please help!

Many thanks

Dear Costumer:

Please follow these steps to see if you can solve your problem:

Step 1. Copy the code into Arduino IDE and upload.

const int GSR=A0;

int sensorValue=0;

int gsr_average=0;

void setup(){



void loop(){

long sum=0;

for(int i=0;i<10;i++) //Average the 10 measurements to remove the glitch



sum += sensorValue;



gsr_average = sum/10;



Step 2. Do not Wear the GSR sensor.

Step 3. Click the Tools-> Serial Plotter from Arduino IDE

Step 4. Use the screw driver to adjust resistor until the serial output as 512.

Step 5. Wear the GSR sensor.

Step 6. We will see the below graph. Please deep breath and see the trends.

Thank you for the reply,

I can confirm I have copy and pasted this code and uploaded it, and the problem still persists. Is the device faulty? and if so, can i exchange it?

Many thanks

Dear Costumer:

I have checked these steps and the sensor worked well. Do you have another Grove GSR sensor v1.2? You could use a new test to determine if it is bad.

I only have one unfortunately. I followed the steps precisely. The problem is that when i use a screwdriver to adjust the resistor screw, i get values jumping wildly and cant ever get it to rest at 512. However, when I connect the sensor to the grove port A2, i can adjust it to 512. But then it does not produce accurate readings of GSR as well, when i wear it. I tried with wet hands and dry hands but it produced the same output. Would you recommend exchanging the model? or is there something I am missing?

Many thanks

Dear Customer:

I used a GSR sensor to test it’s wiki again, and I didn’t find any problem. I have several suggestions for your reference.Hope can help you.

1.Switch needs to be turned to 5V.

2.The sensor need to be connected to A0 Grove.

3.In the wiki’s step2,you can also disconnect finger sleeve with GSR.