Network of temperature sensors

Other Hardware Home Automation
1

Hello guys!
I would like to create a network of temperature sensors located in various rooms.
Arduino UNO is connected with the ethernet shield and send the readings to a server that historicizes the data in a database.
I realized the temperature reading with the sensor LM35DZ (as shown in the example project in the site Arduino Playground - Sensori)
I do not have great experience in electronics, how do I connect the sensors at a distance of several meters Arduino?

Can you please give me an idea where to start?

Thank you and good afternoon!

2

The DS18B20 is a popular thermometer for arduino projects because you can put multiple sensors on a single bus. Some of the Maxim documentation implies that you could run that bus 200 meters or more in good conditions. I suspect that you wouldn't get such performance in your installation, but you may well get enough. You could run a couple of separate buses too, to reduce your cable run lengths.

If network length issues are insurmountable, you may find that you need a satellite Arduino to gather sensor data and send it back to the master. They could communicate over ethernet, wifi, xBee or cheap radios. If you're using either of the first two of course, you could send the sensor data direct to the database server.

3

Thank you wildbill!
Definitely, my house has a distance less than 200 meters... :slight_smile:
If I understand correctly, from ardunino depart three wires: GND, BUS and Vcc to reach the sensor DS18B20, say for 4 meters.
Being the DS18B20 digital is immune to interference.
is it right?

Thank you!!!
Roberto

4

robyg72:
If I understand correctly, from ardunino depart three wires: GND, BUS and Vcc to reach the sensor DS18B20, say for 4 meters.
Being the DS18B20 digital is immune to interference.

You can power the sensors from the bus in what's known as parasite mode, so you don't have to run power. Having said that, I've never been able to get it to work that way.

I wouldn't say that the digital signal makes the DS18B20 immune to interference, but it'll be less likely to be impacted than a sensor that just gives you an analog voltage to read.