Kewngen
Posts: 15
Joined: Thu Jan 30, 2014 10:03 am

SHT10 shows very high (relative) humidity (in soil)

Fri Jun 06, 2014 5:12 pm

I've got 3 SHT10 hooked up to my RPi using rpiSht1x to interact with them.
I have a plastic container with soil that I've buried the sensors in and the soil is pretty dry but a little moist at the depth of the sensors.

This is my output:

Code: Select all

1 Temperature: 22.86 Humidity: 102.589718121 Dew Point: 23.2829120959
2 Temperature: 22.67 Humidity: 102.897743585 Dew Point: 23.1419145396
3 Temperature: 22.51 Humidity: 102.90168428 Dew Point: 22.981979076
The humidity seem a bit to high if you ask me :D

These are my values (from the SHT1x datasheet):

Code: Select all

D1 = -39.65  # for 14 Bit @ 3.3V
D2 =  0.01 # for 14 Bit DEGC
C1 = -2.0468       # for 12 Bit
C2 =  0.0367       # for 12 Bit
C3 = -0.0000015955 # for 12 Bit
T1 =  0.01      # for 14 Bit @ 3.3V
T2 =  0.00008   # for 14 Bit @ 3.3V
The temperature is pretty accurate and all 3 sensors show pretty similar humidity, so I'm guessing they aren't broken?
Any ideas what might be the problem?

I've tried to disconnect 2 sensors to rule out that they don't affect each other but the relative humidity is still over 102.

rpiSht1x: https://pypi.python.org/pypi/rpiSht1x/1.2
Sensors: http://www.aliexpress.com/item/Protecti ... 78403.html

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cyrano
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Location: Belgium

Re: SHT10 shows very high (relative) humidity (in soil)

Fri Jun 06, 2014 11:20 pm

Aren't these supposed to measure AIR humidity? These are capacitive. I don't think that's suitable for soil measurements.

Kewngen
Posts: 15
Joined: Thu Jan 30, 2014 10:03 am

Re: SHT10 shows very high (relative) humidity (in soil)

Sat Jun 07, 2014 6:22 am

I understand your thinking, had that thought as well.

Though since a lot of stores are selling them as soil moisture sensors, (even Adafruit http://www.adafruit.com/product/1298) I think they can measure soil moisture.
Pretty weird scam otherwise :lol:

Kewngen
Posts: 15
Joined: Thu Jan 30, 2014 10:03 am

Re: SHT10 shows very high (relative) humidity (in soil)

Sun Jun 08, 2014 8:39 am

No one knows what the problem might be or where to debug? I've been googling like a maniac without results =/

geoffs
Posts: 15
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Location: Tasmania

Re: SHT10 shows very high (relative) humidity (in soil)

Sun Jun 08, 2014 9:32 am

The ones that Adafruit are selling, are in a waterproof housing.
If your sensor gets wet, then it will no longer be accurate.

Kewngen
Posts: 15
Joined: Thu Jan 30, 2014 10:03 am

Re: SHT10 shows very high (relative) humidity (in soil)

Sun Jun 08, 2014 10:33 am

Mine are (as you can see on the link to the sensor) in a similar kind of housing. Pretty sure they haven't been wet.

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BAStumm
Posts: 134
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Location: Loon Lake, WA USA
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Re: SHT10 shows very high (relative) humidity (in soil)

Mon Jun 09, 2014 2:50 pm

I've used this sensor before but it has been a while. I could look through my code and compare to yours if you want. How are you doing the conversion to come up with the humidity value. Can you share the code?

Kewngen
Posts: 15
Joined: Thu Jan 30, 2014 10:03 am

Re: SHT10 shows very high (relative) humidity (in soil)

Mon Jun 09, 2014 6:34 pm

Definitely! This is the code that I use:

Code: Select all

from sht1x.Sht1x import Sht1x as SHT1x

clkPin = 16

sht1x1 = SHT1x(18, clkPin, SHT1x.GPIO_BOARD)

temperature1 = sht1x1.read_temperature_C()
humidity1 = sht1x1.read_humidity()
dewPoint1 = sht1x1.calculate_dew_point(temperature1, humidity1)

print("1 Temperature: {} Humidity: {} Dew Point: {}".format(temperature1, humidity1, dewPoint1))
This is the code from the rpiSht1x library:

Code: Select all

'''
Created on Oct 5, 2012

@author: Luca Nobili

This modules reads Humidity and Temperature from a Sensirion SHT1x sensor. I has been tested
both with an SHT11 and an SHT15.

It is meant to be used in a Raspberry Pi and depends on this module (http://code.google.com/p/raspberry-gpio-python/).

The module raspberry-gpio-python requires root privileges, therefore, to run this module you need to run your script as root.


Example Usage:

>>> from sht1x.Sht1x import Sht1x as SHT1x
>>> sht1x = SHT1x(11,7)
>>> sht1x.read_temperature_C()
25.22
>>> sht1x.read_humidity()     
52.6564216

'''
import traceback
import sys
import time
import logging
import math

logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

try:
    import RPi.GPIO as GPIO
except ImportError:
    logger.warning("Could not import the RPi.GPIO package (http://pypi.python.org/pypi/RPi.GPIO). Using a mock instead. Notice that this is useful only for the purpose of debugging this module, but will not give the end user any useful result.")
    import RPiMock.GPIO as GPIO
except:
    logger.warning("Could not import the RPi.GPIO package (http://pypi.python.org/pypi/RPi.GPIO). Using a mock instead. Notice that this is useful only for the purpose of debugging this module, but will not give the end user any useful result.")
    import RPiMock.GPIO as GPIO
    traceback.print_exc(file=sys.stdout)
 
#   Conversion coefficients from SHT15 datasheet
D1 = -40.0  # for 14 Bit @ 5V
D2 =  0.01 # for 14 Bit DEGC

C1 = -2.0468       # for 12 Bit
C2 =  0.0367       # for 12 Bit
C3 = -0.0000015955 # for 12 Bit
T1 =  0.01      # for 14 Bit @ 5V
T2 =  0.00008   # for 14 Bit @ 5V
    
class Sht1x(object):
    GPIO_BOARD = GPIO.BOARD
    GPIO_BCM = GPIO.BCM

    def __init__(self, dataPin, sckPin, gpioMode = GPIO_BOARD):
        self.dataPin = dataPin
        self.sckPin = sckPin
        GPIO.setmode(gpioMode)
        
#    I deliberately will not implement read_temperature_F because I believe in the
#    in the Metric System (http://en.wikipedia.org/wiki/Metric_system)

    def read_temperature_C(self):
        temperatureCommand = 0b00000011

        self.__sendCommand(temperatureCommand)
        self.__waitForResult()
        rawTemperature = self.__getData16Bit()
        self.__skipCrc()
        GPIO.cleanup()

        return rawTemperature * D2 + D1
        

    def read_humidity(self):
#        Get current temperature for humidity correction
        temperature = self.read_temperature_C()
        return self._read_humidity(temperature)
    
    def _read_humidity(self, temperature):
        humidityCommand = 0b00000101
        self.__sendCommand(humidityCommand)
        self.__waitForResult()
        rawHumidity = self.__getData16Bit()
        self.__skipCrc()
        GPIO.cleanup()
#        Apply linear conversion to raw value
        linearHumidity = C1 + C2 * rawHumidity + C3 * rawHumidity * rawHumidity
#        Correct humidity value for current temperature
        return (temperature - 25.0 ) * (T1 + T2 * rawHumidity) + linearHumidity            

    def calculate_dew_point(self, temperature, humidity):
        if temperature > 0:
            tn = 243.12
            m = 17.62
        else:
            tn = 272.62
            m = 22.46
        return tn * (math.log(humidity / 100.0) + (m * temperature) / (tn + temperature)) / (m - math.log(humidity / 100.0) - m * temperature / (tn + temperature))

    def __sendCommand(self, command):
        #Transmission start
        GPIO.setup(self.dataPin, GPIO.OUT)
        GPIO.setup(self.sckPin, GPIO.OUT)
                
        GPIO.output(self.dataPin, GPIO.HIGH)
        self.__clockTick(GPIO.HIGH)
        GPIO.output(self.dataPin, GPIO.LOW)
        self.__clockTick(GPIO.LOW)
        self.__clockTick(GPIO.HIGH)
        GPIO.output(self.dataPin, GPIO.HIGH)
        self.__clockTick(GPIO.LOW)

        for i in range(8):
            GPIO.output(self.dataPin, command & (1 << 7 - i))
            self.__clockTick(GPIO.HIGH)
            self.__clockTick(GPIO.LOW)     
        
        self.__clockTick(GPIO.HIGH)
        
        GPIO.setup(self.dataPin, GPIO.IN)
        
        ack = GPIO.input(self.dataPin)
        logger.debug("ack1: %s", ack)
        if ack != GPIO.LOW:
            logger.error("nack1")
        
        self.__clockTick(GPIO.LOW)
        
        ack = GPIO.input(self.dataPin)
        logger.debug("ack2: %s", ack)
        if ack != GPIO.HIGH:
            logger.error("nack2")        
            
    def __clockTick(self, value):
        GPIO.output(self.sckPin, value)
#       100 nanoseconds 
        time.sleep(.0000001)
        
    def __waitForResult(self):
        GPIO.setup(self.dataPin, GPIO.IN)

        for i in range(100):
#            10 milliseconds
            time.sleep(.01)
            ack = GPIO.input(self.dataPin)
            if ack == GPIO.LOW:
                break
        if ack == GPIO.HIGH:
            raise SystemError
            
    def __getData16Bit(self):
        GPIO.setup(self.dataPin, GPIO.IN)
        GPIO.setup(self.sckPin, GPIO.OUT)
#        Get the most significant bits
        value = self.__shiftIn(8)
        value *= 256
#        Send the required ack
        GPIO.setup(self.dataPin, GPIO.OUT)
        GPIO.output(self.dataPin, GPIO.HIGH)
        GPIO.output(self.dataPin, GPIO.LOW)
        self.__clockTick(GPIO.HIGH)
        self.__clockTick(GPIO.LOW)
#        Get the least significant bits
        GPIO.setup(self.dataPin, GPIO.IN)
        value |= self.__shiftIn(8)
        
        return value
    
    def __shiftIn(self, bitNum):
        value = 0
        for i in range(bitNum):
            self.__clockTick(GPIO.HIGH)
            value = value * 2 + GPIO.input(self.dataPin)
            self.__clockTick(GPIO.LOW)
        return value
     
    def __skipCrc(self):
#        Skip acknowledge to end trans (no CRC)
        GPIO.setup(self.dataPin, GPIO.OUT)
        GPIO.setup(self.sckPin, GPIO.OUT)
        GPIO.output(self.dataPin, GPIO.HIGH)
        self.__clockTick(GPIO.HIGH)
        self.__clockTick(GPIO.LOW)
    
    def __connectionReset(self):
        GPIO.setup(self.dataPin, GPIO.OUT)
        GPIO.setup(self.sckPin, GPIO.OUT)
        GPIO.output(self.dataPin, GPIO.HIGH)
        for i in range(10):
            self.__clockTick(GPIO.HIGH)
            self.__clockTick(GPIO.LOW)

class WaitingSht1x(Sht1x):
    def __init__(self, dataPin, sckPin):
        super(WaitingSht1x, self).__init__(dataPin, sckPin)
        self.__lastInvocationTime = 0

    def read_temperature_C(self):
        self.__wait()        
        return super(WaitingSht1x, self).read_temperature_C()
    
    def read_humidity(self):
        temperature = self.read_temperature_C()
        self.__wait()
        return super(WaitingSht1x, self)._read_humidity(temperature)
    
    def read_temperature_and_Humidity(self):
        temperature = self.read_temperature_C()
        self.__wait()
        humidity = super(WaitingSht1x, self)._read_humidity(temperature)
        return (temperature, humidity)
            
    def __wait(self):
        lastInvocationDelta = time.time() - self.__lastInvocationTime
#        if we queried the sensor less then a second ago, wait until a second is passed
        if lastInvocationDelta < 1:
            time.sleep(1 - lastInvocationDelta)
        self.__lastInvocationTime = time.time()
        
def main():
    sht1x = WaitingSht1x(11, 7)
    print(sht1x.read_temperature_C())
    print(sht1x.read_humidity())
    aTouple = sht1x.read_temperature_and_Humidity()
    print("Temperature: {} Humidity: {}".format(aTouple[0], aTouple[1]))
    print(sht1x.calculate_dew_point(20, 50))
    
if __name__ == '__main__':
    main()
And that code is a port of this library:
https://github.com/practicalarduino/SHT1x

Really appreciate your help!

User avatar
BAStumm
Posts: 134
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Location: Loon Lake, WA USA
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Re: SHT10 shows very high (relative) humidity (in soil)

Mon Jun 09, 2014 8:15 pm

Sorry, I am not a python guy... I code in C.

Here is what I'm using, for what it's worth...

One thing to check is that you are reading 14 bit temp and 12 bit hum values... not 12 and 8.

Code: Select all


/*
 * dlp_read_hum
 *	- read humidity from DLP-TH1 sensor
 */
int dlp_read_hum(_dlp_th1 *dlp) {
	unsigned char msb, lsb, crc, ret_crc;
	FT_STATUS ftStatus;
	double rhlin, rhtrue, es, ee;
	int busy, i, temp;
	
	// check that device is open
	if (!dlp->isOpen) return FAILURE;
	
	dlp_reset_sensor(dlp);						// reset sensor
	dlp_write_byte(dlp, DLPTH1CMDHUM);		// write measure hum command
	
	// wait for conversion to finish
	busy = 1;
	while (busy) {
		ftStatus = FT_GetBitMode(dlp->ftHandle, &dlp->data);
		if (ftStatus != FT_OK) {
			printf("dlp_read_temp: FT_GetBitMode failed.\n");
			return FAILURE;
		}
		
		busy = dlp->data & 0x02;
		
		// sleep for 10 ms
		Sleep(10);
	}
	
	// read temp data
	msb = dlp_read_byte(dlp, 0);
	lsb = dlp_read_byte(dlp, 0);
	crc = dlp_read_byte(dlp, 1);
	
	// process CRC for the command byte
	dlp->dowcrc = 0;
	dlp_calcrc(dlp, 5);
	dlp_calcrc(dlp, msb);
	dlp_calcrc(dlp, lsb);
	
	// reverse bit order of the returned checksum
	ret_crc = crc;
	crc = 0;
	for (i=0; i<8; i++) {
		crc <<= 1;
		if (ret_crc & 0x01) crc |= 0x01;
		ret_crc >>= 1;
	}
	
	// check for bad reading	
	if (crc != dlp->dowcrc) {
		printf("dlp_read_temp: Bad CRC. Temp reading failed.\n");
		
		dlp->degc = (double)999;
		return FAILURE;
	}
	
	// got a good reading, calc humidity
	temp = lsb | (msb << 8);
	rhlin = -4.0 + (.0405*(double)temp) + (-2.8e-6*(double)temp*(double)temp);
	rhtrue = (dlp->degc - 25.0) * (.01 + .000008 * temp) + rhlin;
	dlp->hum = rhtrue;
	
	// calculate dewpoint
	es = 6.112 * pow(10,((7.5*dlp->degc)/(237.7+dlp->degc))); 
	ee = dlp->hum * es / 100; 
	dlp->dewp = (237.7*log10(ee/6.112))/(7.5-log10(ee/6.112));

	return SUCCESS;
}

User avatar
BAStumm
Posts: 134
Joined: Fri Aug 23, 2013 3:37 pm
Location: Loon Lake, WA USA
Contact: Website

Re: SHT10 shows very high (relative) humidity (in soil)

Mon Jun 09, 2014 8:41 pm

For some reason my C1, C2 and C3 values are different... not sure why. It's been a couple years since I worked on that project.

C1 = -4.0
C2 = .0405
C3 = -2.8e-6

Kewngen
Posts: 15
Joined: Thu Jan 30, 2014 10:03 am

Re: SHT10 shows very high (relative) humidity (in soil)

Tue Jun 10, 2014 7:37 am

Thanks alot BAStumm!

I will first try to change my values to match yours and if that doesn't work I'll try your code.
Could you just do a simple step-by-step on how to use your code?

I'll try the stuff as soon as I get home from work.

Kewngen
Posts: 15
Joined: Thu Jan 30, 2014 10:03 am

Re: SHT10 shows very high (relative) humidity (in soil)

Tue Jun 10, 2014 11:30 am

Your values seem to be for the V3 sensors and my values for the V4. Since I've bought my sensors from Kina I recon it's a good chance I have V3 sensors.

From the SHT1x datasheet:

Code: Select all

SORH       c1         c2          c3 
12 bit     -2.0468    0.0367     -1.5955E-6 
8 bit      -2.0468    0.5872     -4.0845E-4 
Table 6: Optimized V4 humidity conversion coefficients 

The values given in Table 6 are newly introduced and 
provide optimized accuracy for V4 sensors along the full 
measurement range. The parameter set cx*, which has 
been proposed in earlier datasheets, which was optimized 
for V3 sensors, still applies to V4 sensors and is given in 
Table 7 for reference. 
 
SORH         c1*       c2*       c3* 
12 bit      -4.0000    0.0405    -2.8000E-6 
8 bit       -4.0000    0.6480    -7.2000E-4 
Table 7: V3 humidity conversion coefficients, which also apply 
to V4. 
Hopefully this will solve my problem!

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Burngate
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Location: Berkshire UK
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Re: SHT10 shows very high (relative) humidity (in soil)

Tue Jun 10, 2014 4:58 pm

Having read through the above posts, several things strike me

The measured temperatures appear to be reasonable, so the sensor appears to be working, and what's more the Pi is comunicating with it correctly.

The various factors D1, D2, T1, T2, C1, C2, C3 are only tweaks to be applied after a reading has been obtained. Changing them won't make any difference if the reading is wrong.

102% sounds suspiciously like the reading is full-scale - that is 4095 out of 4095, or FFF - so somewhere between asking for humidity and converting to percentage, the code is going wrong. Perhaps it's asking for the wrong register, or maybe it's ignoring the answer. I'm no expert at either Python or C, but I'd try throwing away all the niceties in the code, and just leave the bare bones, to see what the sensor's sending back.

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BAStumm
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Joined: Fri Aug 23, 2013 3:37 pm
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Re: SHT10 shows very high (relative) humidity (in soil)

Tue Jun 10, 2014 8:12 pm

I suspect the sensor is contaminated. Have you tried getting readings from air instead of in the soil? Sensirion (the manufacturer of the sensor being used on whatever breakout board you have) have suggested to me previously to bake the sensor for a few hours to remove contamination. I'd have to review e-mails to get the time/temp but I think it was something like 170F degrees for many hours. The plastic housing may need removed.

As for using my C code, my sensor is USB connection so the code may not port directly. Plus it is part of a MUCH larger project that reads MANY other sensors and controls motors. It would take me a bit to extract the relevant parts to make a working code set that you could compile.

Kewngen
Posts: 15
Joined: Thu Jan 30, 2014 10:03 am

Re: SHT10 shows very high (relative) humidity (in soil)

Wed Jun 11, 2014 7:43 am

Burngate wrote:Having read through the above posts, several things strike me

The measured temperatures appear to be reasonable, so the sensor appears to be working, and what's more the Pi is comunicating with it correctly.

The various factors D1, D2, T1, T2, C1, C2, C3 are only tweaks to be applied after a reading has been obtained. Changing them won't make any difference if the reading is wrong.

102% sounds suspiciously like the reading is full-scale - that is 4095 out of 4095, or FFF - so somewhere between asking for humidity and converting to percentage, the code is going wrong. Perhaps it's asking for the wrong register, or maybe it's ignoring the answer. I'm no expert at either Python or C, but I'd try throwing away all the niceties in the code, and just leave the bare bones, to see what the sensor's sending back.
When I changed the C values the sensors returned 100% instead of above. So I think that was the problem on that part.
When I scrape of the driest soil and put in another container and put a sensor in there it shows about 95%. That's really dry soil though.
BAStumm wrote:I suspect the sensor is contaminated. Have you tried getting readings from air instead of in the soil? Sensirion (the manufacturer of the sensor being used on whatever breakout board you have) have suggested to me previously to bake the sensor for a few hours to remove contamination. I'd have to review e-mails to get the time/temp but I think it was something like 170F degrees for many hours. The plastic housing may need removed.

As for using my C code, my sensor is USB connection so the code may not port directly. Plus it is part of a MUCH larger project that reads MANY other sensors and controls motors. It would take me a bit to extract the relevant parts to make a working code set that you could compile.
I was just about to email Sensirion. I'm starting to think cyrano (second post in thread) is right, are they really meant for soil moisture?

They show around 50% RH in my house, sadly I don't have any other hygrometer at home to compare with. But 50% sounds reasonable to have indoors, right?

Are you or have you been using the sensors in soil?

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BAStumm
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Re: SHT10 shows very high (relative) humidity (in soil)

Wed Jun 11, 2014 12:23 pm

I use them in air.

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BAStumm
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Re: SHT10 shows very high (relative) humidity (in soil)

Wed Jun 11, 2014 12:59 pm

You can test accuracy of the sensor with a salt solution...

Table salt is sodium chloride (NaCl), which provides 75% RH at room temperature ~70F/20C. Take a cup and put a few tablespoons of table salt in it. Add water to make a slurry, it will look like wet sand so not much water maybe 1 tablespoon water to 4 tablespoons salt. Put this cup in a bag and put the sensor in the cup so it doesn't touch the salt but is close. Seal the bag as tightly as you can around the wires (rubber band). Wait about an hour for things to stabilize then take your reading, you should read 75% RH.

I use a three point calibration system. MaCl provides 33% and LiCL provides 11%. MaCl is often used as deicer for roads and driveways. I buy it at a construction supply store in a huge jug for about $5. The LiCl I had to order in a small quantity off ebay for a few dollars. There are other calibration salts but they are harder to come by. See this info below.

http://www.omega.com/temperature/z/pdf/z103.pdf

Kewngen
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Joined: Thu Jan 30, 2014 10:03 am

Re: SHT10 shows very high (relative) humidity (in soil)

Wed Jun 11, 2014 1:27 pm

Awesome, thanks. Will try it out!

ulij
Posts: 2
Joined: Mon Sep 29, 2014 12:29 pm

Re: SHT10 shows very high (relative) humidity (in soil)

Mon Sep 29, 2014 12:58 pm

Not sure if that helps, but usually you cannot use air humidity sensors for measuring soil moisture.
The reasons is mainly because the tension on the electrodes changes the soil around the sensor and the electrodes itself (depending on the material used).
Usually you would use tensiometers for soil moisture, but they are fairly expensive.
I've got a watermark soil moisture sensor at home, but I need some sort of adapter that allows to read the sensor from a PI. From what I understood you need to alternating current for probing in order not to destroy the capacitative sensor.

gnlcyber
Posts: 1
Joined: Sat Feb 14, 2015 8:10 pm
Location: South Africa

Re: SHT10 shows very high (relative) humidity (in soil)

Sat Feb 14, 2015 8:58 pm

I saw your post on the SHT10...
Kewngen wrote:I've got 3 SHT10 hooked up to my RPi using rpiSht1x to interact with them.
I have a plastic container with soil that I've buried the sensors in and the soil is pretty dry but a little moist at the depth of the sensors.

This is my output:

Code: Select all

1 Temperature: 22.86 Humidity: 102.589718121 Dew Point: 23.2829120959
2 Temperature: 22.67 Humidity: 102.897743585 Dew Point: 23.1419145396
3 Temperature: 22.51 Humidity: 102.90168428 Dew Point: 22.981979076
The humidity seem a bit to high if you ask me :D

These are my values (from the SHT1x datasheet):

Code: Select all

D1 = -39.65  # for 14 Bit @ 3.3V
D2 =  0.01 # for 14 Bit DEGC
C1 = -2.0468       # for 12 Bit
C2 =  0.0367       # for 12 Bit
C3 = -0.0000015955 # for 12 Bit
T1 =  0.01      # for 14 Bit @ 3.3V
T2 =  0.00008   # for 14 Bit @ 3.3V
The temperature is pretty accurate and all 3 sensors show pretty similar humidity, so I'm guessing they aren't broken?
Any ideas what might be the problem?

I've tried to disconnect 2 sensors to rule out that they don't affect each other but the relative humidity is still over 102.

rpiSht1x: https://pypi.python.org/pypi/rpiSht1x/1.2
Sensors: http://www.aliexpress.com/item/Protecti ... 78403.html
and i was wondering where you got the info on wiring it up to the pi and implementing the code?
I purchased a DB130 sensor http://www.dfrobot.com/index.php?route= ... ption=true
But i heard it is based on the sht10 sensor but i cannot find any help to get this connected and working on a raspberry. Any help would be appreciated. thanks

mehdi.heris
Posts: 2
Joined: Fri Mar 10, 2017 1:11 am

Re: SHT10 shows very high (relative) humidity (in soil)

Fri Mar 10, 2017 1:14 am

Hi Kewngen,

Did you figure out the problem. Would you mind sharing your code with me?

Thanks,
Mehdi

Adriaan
Posts: 1
Joined: Sun Jan 14, 2018 9:03 am

Re: SHT10 shows very high (relative) humidity (in soil)

Sun Jan 14, 2018 9:12 am

Good morning/afternoon/evening gents,

Last week I installed a SHT10 on a PI3B. Did some testing and both temp and humm are beeing measered. When keeping the SHT10 in the air the values are as could be expected.

BUT after placing the sensor in soil the hummidity seems way TOO high. 99% most of the time.

So I searched for same issues and that brought me here.

Should I 'fix' something in the sample script (sensor.py) that comes with pi_sht1x distro?

Hope to hear and TIA.

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