Hi i have used DHT22 Sensor with arduino but i am unable to get the signal from long distance
can some guide me
Distence is approx 100 mtrs
Waiting for response
Thanks In advance

 

hi. H,
The DHT22 sensor will not drive over a 100mtr cable, its much too long.
The best I have done is about 2-3 mtrs, do you have the pull up resistors on the Dta and Clk lines.?
E

 

1st step: conditionize Your sensor (opamps) let the minimum TTL levels be in the output
2nd step: apply the optical fiber genuine transmitter/receiver, for example HFBR 23XX (I am telling by memory, pardon if one figure may be not exact). Then 10 kilometers will not be the highest possible result. The 10 nanosec is sth possible for such lines.

 

Consider using a plastic FO link.

https://www.digikey.com/en/supplier...MI3OODwaaU3AIVQr7ACh2hIAt9EAAYAyAAEgLEmfD_BwE

Or use -

https://www.embedded.com/design/connectivity/4023975/Serial-Protocols-Compared

Then there is wireless using ESP8266 or various manufacturer 400 Mhz wireless chips.

Regards, Dana.

 

Conditioning and driver circuits need power. What power sources are available out where the sensor is?

ak

 

To review.
We have 5V digital system.
We have distance of 100 meters.

If you ok with wired system, stick a bunch of Uno/Nano/Mini/Micro boards as repeaters.

1.8 km wireless: http://www.instructables.com/id/Long-Range-18km-Arduino-to-Arduino-Wireless-Commun/

Useful experimental info: https://arduino.stackexchange.com/q...for-serial-communication-between-two-arduinos

 

Since the remote sensor output already is a 5 V logic signal (frequency/period/bandwidth unknown), I recommend an RS-422 or RS-485 transmitter as a cable driver. 4-wire cable gets you +5 V and GND outbound to power the sensor and transmitter, and +/- balanced serial data back to a receiver. Lotsa decoupling caps at the far end to stabilize the transmitter output impedance.

ak

 

This site..
https://randomnerdtutorials.com
has a great tutorial on this and a lot of other stuff. I recommend having a good look through it. They have done a good job putting a lot of info on line.
For example...
https://randomnerdtutorials.com/esp...ure-and-humidity-web-server-with-arduino-ide/
I bought their books too.

 

Thanks everyone
But i have found that we can convert signal from one type another one but didnt get proper information
can some one guide me
I have found DS2450 which is used to convert analog voltage to convert in one wire but how can i use it with my circuit
Thanks AGAIN

 

I have also find LM35 which analog sensor and can be used but mV signal can not be used over large distence due to drop
can we convert it in PWM Modulation
if yes Then how
THANKS IN ADVANCE
WAITING FOR RESPONSE

 

hi H,
Have you seen page #7, Fig #4 of the LM35 datasheet.?
It is a circuit for long cable connections, I have used it upto 20mtrs OK.

Do you have a MCU at the end of the 100mtr where the temperature sensor needs to be located.??
E

 

ATTINY one way using its A/D and PWM and a small amount of basic code.

https://www.mcselec.com/

Or PSOC -



SAR A/D could also be used to monitor more sensors, and monitor power supply
at sensor location for warning out of spec conditions. PSOC takes SAR value and
converts it to duty cycle value for use to control the PWM, simple code. PSOC has
accurate onboard reference as well. Only part of the capability of PSOC. Could
also be sued to "linearize" low cost sensors.

Regards, Dana.

 

HI DANADAK
THANKS
Can you explain me in detail how i can do this
If i use ATTINY ADC then how i can use it
and if use say PSOC then what is this
Thanks
Waiting for response

ATTINY one way using its A/D and PWM and a small amount of basic code.

https://www.mcselec.com/

Or PSOC -

View attachment 156016

SAR A/D could also be used to monitor more sensors, and monitor power supply
at sensor location for warning out of spec conditions. PSOC takes SAR value and
converts it to duty cycle value for use to control the PWM, simple code. PSOC has
accurate onboard reference as well. Only part of the capability of PSOC. Could
also be sued to "linearize" low cost sensors.

Regards, Dana.

 

I'm looking into there...
https://www.aliexpress.com/item/2pc...8418-4e3f-9e51-117ac99591fe&priceBeautifyAB=0

 

I have also find LM35 which analog sensor and can be used but mV signal can not be used over large distence due to drop
can we convert it in PWM Modulation
if yes Then how
THANKS IN ADVANCE
WAITING FOR RESPONSE

Stick another Arduino board on it.

 

If i use ATTINY ADC then how i can use it
and if use say PSOC then what is this

ATTINY is a low end UP, and you can use BASCOM Basic language to program it.
On their web site are examples and links to videos on how to design.

PSOC is a UP with analog capability as well. Look at www.cypress.com website,
video section "PSOC Creator 101", or google that, a series of lessons on how
to use.

Regards, Dana.