first one wire exposure

I have messed with switches, leds. Now I am interested in messing with a sensor.

I was curious which one wire temp sensor is best for a beginner? Considering libraries available for arduino.

Would the ds18b20 be a good choice for me?
url: One-Wire Ambient Temperature Sensor - MAX31820 - SEN-14049 - SparkFun Electronics

Thanks in advance.
Steve.

I personally think 1-wire is a bit of pain in the neck, but the libraries available should take a lot of the sting out of it. Physically it’s really nice, because you only need 2 wires, and it can run a long way (up to 100’ or 100m, something like that).

Due to some problems with environmental control at work, I’ve got a bit of a Thing about measuring temperature, so I’ve explored a bit and played with a few temp sensors. Here are some options:

  • DS1820/DS1821 family - 1-wire interface, a few variants
  • DS1722 - SPI interface. I have example code (can;t recall if I posted it on the forum).
  • DS1621/DS1631 - I2C interface (1631 has to be strapped for I2C mode). I2C is pretty easy, both electrically, physically, and software-wise with the Arduino. Others have posted working code (or references to same) on the forums here.
  • LM35 - an analog device that puts out a voltage proportional to the temperature (0.01V/deg C). You’d use this with an analog input.
  • thermistor - a resistor whose resistance varies based on temperature (sometimes inversely, sometimes not). An analog circuit that typically needs a voltage divider network and some math to get a temperature out of it.
  • MAX6675 - thermocouple interface IC. This one speaks SPI and has a place to connect a K-type thermocouple. Good for larger temperatures.
    There are others; Microchip and TI have temp sensors that speak SPI or I2C, for example.

I’ve found playing with temperature sensors to be quite useful, as the results are easy to check (thus eliminating a variable when troubleshooting), lots of examples are available, and once you get an abc-interfaced temp sensor working, for example, it’s a bit easier to get an abc-interfaced xyz sensor working.

-j

I personally think 1-wire is a bit of pain in the neck, but the libraries available should take a lot of the sting out of it. Physically it’s really nice, because you only need 2 wires, and it can run a long way (up to 100’ or 100m, something like that).

Due to some problems with environmental control at work, I’ve got a bit of a Thing about measuring temperature, so I’ve explored a bit and played with a few temp sensors. Here are some options:

  • DS1820/DS1821 family - 1-wire interface, a few variants
  • DS1722 - SPI interface. I have example code (can;t recall if I posted it on the forum).
  • DS1621/DS1631 - I2C interface (1631 has to be strapped for I2C mode). I2C is pretty easy, both electrically, physically, and software-wise with the Arduino. Others have posted working code (or references to same) on the forums here.
  • LM35 - an analog device that puts out a voltage proportional to the temperature (0.01V/deg C). You’d use this with an analog input.
  • thermistor - a resistor whose resistance varies based on temperature (sometimes inversely, sometimes not). An analog circuit that typically needs a voltage divider network and some math to get a temperature out of it.
  • MAX6675 - thermocouple interface IC. This one speaks SPI and has a place to connect a K-type thermocouple. Good for larger temperatures.
    There are others; Microchip and TI have temp sensors that speak SPI or I2C, for example.

I’ve found playing with temperature sensors to be quite useful, as the results are easy to check (thus eliminating a variable when troubleshooting), lots of examples are available, and once you get an abc-interfaced temp sensor working, for example, it’s a bit easier to get an abc-interfaced xyz sensor working.

-j

I found that I had some lm35’s on hand, so I will try that first. I am more interested in the one wire stuff, but this will be an easy start.

Question about the lm35: if the temp that I am testing is some distance (maybe 10 ft from the arduino, how do I run the leads? Can I have 10ft leads?

A co-worker has a brother taking IT in Moscow. I showed the co-worker the arduino and I hope he gets his brother into it.

Thanks for the info.
Steve.

I haven't explored the LM35 much, I just happen to have a few toys on hand (various OpenTracker models) that use them.

10' seems a bit long; I suspect the LM35 will probably work, but you may have a bit of noise.

You can always test by hooking up two, one on short leads and one on 10' of wire, but make a single large loop of wire so that the two are physically side by side.

-j