What would it take to build a web-accessible temp monitor?

MalFet said:

That's great. Looks like a super-simple solution.

You didn't need to solder on any kind of pull-up resistor? Did it come with instructions about which terminals on the phone cable each of the legs on the sensor went to, or did you have to figure that out separately?

Click to expand...

No resistor. There are very good images of the wiring diagrams on the hobby boards site *where I got me adapter. And I still accidentally wired it backwards, with no seeming ill effects other than it just didn't work.

About the only thing I think I would like better is better instructions from the guy who wrote the Logtemp software. It's very capable, and for the most part not too hard to figure out, but I wish there were more tutorials to help you out.

Here's a couple of shots of the hardware:


You can see how tiny this thing is, and how it's wired.



Here is the USB adapter, which communicates with each sensor on the network. You can daisy chain multiple sensors easily by connecting the data wire from one to the next. They each have a unique hardware serial number, so your adapter always knows which one it's communicating with, and there is no need for more than 1 wire since it's polling based on the serial numbers.

You can also see the standard telephone cable. You could wire a CAT5 network cable in here as well if you had a crimper and basic wiring knowledge. This setup so far has only a raw sensor. They also make these things prebuilt with a sensor on a small board with 2 connectors, to make wiring super easy. One cable goes to the adapter, and the other goes to the next sensor. I chose this way because I wanted to be able to place the sensor directly into the thermowell. The telephone wire is too thick, though, so I'll have to replace it with something that will slide into the probe better.

Very cool. Thanks for the photos. I've got mine hooked up to usb cable right now, just because it is what I had sitting around. I wonder if anyone is making pre-wired probes and thermowells with telephone cable jacks. It would make this kit much more user-friendly for people scared of soldering.

Yeah, that would be nice for a lot of people. I could use a smaller soldering gun to do a better job, and different wire. I threw this together with a piece of phone cable I had laying around. I could see someone buying a spool of cable, and a box of connectors and selling these things for like $5 each, or maybe even less in a package deal. I think the 5 connectors I bought cost $7 plus a bit for shipping. decent wire and connectors are cheap.

Heck I could probably have a guy here at work show me how to best weld up a nice thermowell probe...

Here are some links that I've been using:

Logtemp software for connecting to the USB (or serial) adapter. Note they have the program download just a little ways down the page and a link to the driver just the same as the one here below.

Download page for the Adapter Driver. (Maxim-IC)

Hobby Boards where I bought the USB adapter. They have several different types of sensors and boards, including hubs, which can expand the network from a daisy chain linear topography, to a star topography (allows for several runs of sensors to different directions). They also have a very nice How-To on 1-wire set up.

I bought the individual sensors from some overseas Ebay site. But they came in extremely quickly.

Note that there are a few different software packages that you could use besides Logtemp. This is just the first one I tried and it looked like it had plenty of options. There are more links within the Hobby Boards pages.

I think I've figured out the FTP problem... I do not have FTP enabled on my server apparently. I have SecureFTP enabled, but I guess Logtemp doesn't support it. I used port 22, which was normal, and got a response from my server that wasn't very descriptive. Something about SSH version whatever... Nothing that would jog my memory about disabling FTP.

Anyway, I loaded up the credentials to our company's hosted FTP and it works pretty slick. I may have to see about turning on FTP and limiting it's access somehow, or find a program that can transfer the graph to my server using SFTP automatically...