Temperature Sensors

[RichardU]

I'm hoping to add about 6-8 temperature sensors to my system which includes an M1G and CQC. I don't want to use the M1 sensors because they get pricey for that many. I'd be happy to add an Arduino / R Pi etc. Does anyone have any recommendations?
 

 

[potts.mike]

http://store.qkits.com/moreinfo.cfm/vk011

CQC has a driver for this device. It supports four one wire temp sensors at 40$.

 

[pete_c]

You can get 1-wire temperature sensors relatively inexpensively on Ebay.  Aside from Arduino / R Pi you can utilize PogoPlugs or a Seagate Dockstar.
 
Personally here I utilize Seagate Dockstars.  I use either a Maxim 9097 serial with a USB adapter.  I also found this small 1-wire USB dongle with dual ports on Ebay.  It came with two cabled temperature probes.  I made a separate 1-wire network for it using a stereo earphone jack.

 

[RichardU]

Thanks, guys. I'll check out the VK011.
 
I'm a little confused by the PogoPlug and Seagate Dockstar. From what I can tell they are a cloud storage and NAS device. Not sure how that helps me read temperatures.

 

[pete_c]

I repurposed my PogoPlug and Seagate Dockstar such that I could boot into Debian and Arch Linux using a USB stick.
 
The Arch Linux Seagate Dockstar is running my sprinkler application and has a 1-wire connection.
 
Its plug n play (almost) for the 1-wire sensors
 

$ apt-get install digitemp    # 1-wire sensor readout
$ cd /usr/bin
root@debian:/usr/bin# ln -s digitemp_DS9097 digitemp # select interface type
$ apt-get install minicom     # for serial link
$ apt-get install gnuplot     # plot program
$ apt-get install python      # 2.6.5-13
http://packages.debian.org/squeeze/python-serial
$ apt-get install python-serial # interface for serial link (RS232)
$ apt-get install ttf-bitstream-vera # simple sans font for gnuplot

Tests:
$ uvccapture -x352 -y288      # gives shot.jpg from the webcam
$ digitemp -s /dev/ttyUSB0 -i # initialize resource file .digitemprc
$ digitemp -a                 # show temperature from sensor DS18S20

 

 

[RichardU]

Thanks Pete.

 

[maltesemanTS1]

LM35/LM45 $4.76 ea (http://www.digikey.com/product-detail/en/LM35CZ%2FNOPB/LM35CZ%2FNOPB-ND/20744)
TMP35 $1.42 ea (http://www.digikey.com/scripts/DkSearch/dksus.dll?WT.z_header=search_go&lang=en&keywords=TMP36GT9Z-ND&x=0&y=0&cur=USD)
 
I use the TMP35 with my Arduino Uno.
 
"The TMP35 is functionally compatible with the LM35/LM45and provides a 250 mV output at 25°C. The TMP35 reads temperatures from 10°C to 125°C. The TMP36 is specified from −40°C to +125°C, provides a 750 mV output at 25°C, and operates to 125°C from a single 2.7 V supply. The TMP36 is functionally compatible with the LM50. Both the TMP35 and TMP36 have an output scale factor of 10 mV/°C.The TMP37 is intended for applications over the range of 5°C to 100°C and provides an output scale factor of 20 mV/°C. The TMP37 provides a 500 mV output at 25°C. Operation extends to 150°C with reduced accuracy for all devices when operating from a 5 V supply." http://www.analog.com/static/imported-files/data_sheets/TMP35_36_37.pdf