GrovePi - Alcohol Sensor reading problem


#1

Hi,

I am trying to build alcohol sensor, with GrovePi Alcohol sensor (Seeed Studio).

The problem is when sensor is disconnected from the board getting reading between 0 to 150.
but when sensor is connected to the board getting constant reading 1023.

I am using following python code:

#############################################################################

import time
import grovepi

hcho_sensor = 0

grovepi.pinMode(hcho_sensor,“INPUT”)

grove_vcc = 5

while True:
try:
# Get sensor value
sensor_value = grovepi.analogRead(hcho_sensor)

    # Calculate voltage
    voltage = (float)(sensor_value * grove_vcc / 1024)

    print ("sensor_value =", sensor_value, " voltage =", voltage)
    time.sleep(.5)

except IOError:
    print ("Error")

#################################################################################


#2

That reading seems to indicate that the sensor is maxing out. It looks like your analog port is working fine. You may want to try to replace the sensor.