Attaching one-wire sensors to max/min thermometers - total newbie, sorry

[Sciencechick]

Hi all, apologies in advance if this is a silly question, but I am NOT well versed in electronics, I have trawled the net for an answer, but....I just need to know if this can be done...

I have a DS18b20 thermal probe - this one: https://www.sparkfun.com/products/11050

What I would like to do is attach this to a digital max/min thermometer such as this one :http://www.ebay.co.uk/itm/Digital-T...729?pt=LH_DefaultDomain_3&hash=item256ec54fc9

Can this be done????

Why do I want to do this you may ask as the above max/min thermometer already has a probe? Well, the probes that come with these digital thermometers routinely measure accurately to within 1°C whereas the DS18b20 measures to within 0.5°C and I need this level of accuracy for a science investigation into max/min temperatures underwater. I have tried to find a battery-powered max/min thermometer with a submersible sensor accurate to 0.5°C and I have found a few - but they cost many ££££s!

Is it likely that if I crack open the back of a digital thermometer such as the one above that I will be able to remove the existing probe and attach my DS18b20 to it - or am I totally wide of the mark? Many thanks.

 

[BobK]

Not likely unless the unit uses the same protocol (1-wire) and data format.

If you can find someone who can build microcontroller projects, it would not be difficult to make one that read the probe and kept min and max temps.

Bob

 

[davenn]

Not likely unless the unit uses the same protocol (1-wire) and data format.
If you can find someone who can build microcontroller projects, it would not be difficult to make one that read the probe and kept min and max temps.

Bob

I agree with Bob's comments
The likelihood is that the probe on that eBay thermometer is a more basic sensor with an analog rather than digital output
If you want to use that other probe you found, you will need a circuit designed to read its digital signal


Dave

 

[Sciencechick]

I agree with Bob's comments
The likelihood is that the probe on that eBay thermometer is a more basic sensor with an analog rather than digital output
If you want to use that other probe you found, you will need a circuit designed to read its digital signal


Dave

Thanks BobK and Dave - I suspected as much. I have found a web tutorial with instructions on how to make the thing I'm after:
http://www.electronicslovers.com/2015/03/arduino-based-temperature-meter-will.html
http://www.electronicslovers.com/2015/03/arduino-based-temperature-meter-will.html
This looks almost basic enough for me to follow - does it look workable to you guys? My next (and last! I hope) question is about the power supply. I need this contraption to work outdoors away from mains power for at least 24 hours. The above tutorial suggests using 9v DC battery with regulated IC or a 5v battery. It seems impossible to find a 5v battery (?) and I have been told by one person that the 9v method may not give me enough hours of power - would you concur? And is there any possibility I could use 4 x 1.5v AA batteries with this design? Thanks again in advance for your help.

 

[Harald Kapp]

And is there any possibility I could use 4 x 1.5v AA batteries

Make sure you get one of the 3.3V models . They have an on-board regulator and will work from an input voltage (raw pin) as low as 3.35V.
You can directly connect it to a pack of 3*AA batteries.