dallas 1 wire temp sensors

Forum 2005-2010 (read only) Hardware Interfacing
1

hello,

I am running an arduino with 3- 1 wire sensors in my green house.... they have been working great for months.... and now they are all reading 32 deg F with no change when heated...... looked for loose connections etc but not sure what to do next..... any Ideas

Thanks

Troy

2

Are they all reporting back their unique ID number correctly, if so then most of it would appear to be working and that checks the wiring as well.
Have you made any changes to the software?
Then try replacing just one sensor.

3

and now they are all reading 32 deg F with no change when heated

Could also be moisture. As the nights are getting colder this may also affect cabling. You could try with a led at the end of the cable to test if the temp sensors get their 5Volts.

Furthermore 32F is 0 Celsius, and that number allways triggers me. Could you share some code?

4

Thanks.... will try the led at the end of the line.... and I will post my code when i get to my laptop. If moisture is an issue should I be using a diffferent sensor..... thermistors?

Thanks for the replies

Troy

5

The moisture isn't a problem with the sensors as such but can be a problem with the wiring if you have any of it exposed you can get shorts or leakages between the signal and ground wires.