More crack for controller junkies - NFCS web software

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Nofossil

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With Mrs. NoFossil away for a couple of days, I've made more progress on the software end of things. Once again I'm looking for suggestions and/or constructive criticism.

At this point the software can process text-based rulesets, allowing it to set outputs based on inputs and rules. No programming, no compiling. The web interface allows monitoring of system inputs, outputs, and values computed by processing rules. It also displays the current rules. The next step is point-and-click rule creation and editing.

Right now, I have the prototype controller set up so that the 'Main Floor Zone Valve' output drives a night light that's next to the main floor sensor. The main floor setpoint is 78 degrees with a 2 degree deadband, so the zone valve output goes on at 76 degrees and off at 78 degrees. The night light heats up the sensor pretty quickly, so you can watch it cycle. The 'Wood Boiler Outlet' is actually disconnected - I don't really have anything at 255 degrees.

It's at http://www.nofossil.org:7261/cgi-bin/webmonitor

For real hard-core folks, I'll be glad to provide a pointer to the source code.

I've also fixed a broken piece of network hardware, so outside access to my web sites should be a good deal more snappy.
 

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nofossil,

Could you provide a link to the source code?

Also, can you provide and active web page where us experts on the boiler forum can change your main flow settings and add our own rules?

We promise to keep you warm :)

Thanks,
Steve
 
SteveJ said:
nofossil,

Could you provide a link to the source code?

Also, can you provide and active web page where us experts on the boiler forum can change your main flow settings and add our own rules?

We promise to keep you warm :)

Thanks,
Steve

I appreciate the kind offer, Steve, but after setting my house lights up for web-based control back in 2001, I decided that some things I just want to keep to myself. Just kinda selfish that way, I guess.....

I do plan on making the development system available for web-based programming and control from time to time. Have to figure out how to avoid several people all making changes at once, though. By the way - I've unplugged the light that I referred to in the original post. It was pretty cool, though. My daughter made a scale model of our house out of cardboard. Maybe I'll set that up with Christmas lights for zone heat sources. With a webcam, you could watch the zones come on and off.....

This is way early, but all the files are here.

The source code is released under the Gnu Public License (GPL). That means (short version) you can use it any way that you want, but must credit the original source and make any derivative versions available in the same way.

Please note that this is a work in progress and files are changing just about every day. The set of files listed above may or may not even compile on any given day.

If you make changes (especially improvements) I'd really like the chance to incorporate them in the original code - with credit, of course. My main goal in releasing this is to eventually build a community of users and contributors.

For those of you who are system installers, what specific features would make a controller like this most useful? What are the unsolved control-related problems out there?
 
Looks like you have done a lot of work on this.
I don't want to sound critical, just curious, why not just use a commercial PLC?
They have gotten a lot cheaper and very robust. I don't have any analog inputs but I'm using a $140 PLC to control my oil burner, EBW 100, air handler and zone valves with inputs from my thermostat, aquastats and the pumps on the wood boiler. I have already made provisions for the storage tanks when they are installed.
There are some very nice PLC's with built in displays that would seem to be a good choice for what you are doing.
 
kgryder said:
Looks like you have done a lot of work on this.
I don't want to sound critical, just curious, why not just use a commercial PLC?
They have gotten a lot cheaper and very robust. I don't have any analog inputs but I'm using a $140 PLC to control my oil burner, EBW 100, air handler and zone valves with inputs from my thermostat, aquastats and the pumps on the wood boiler. I have already made provisions for the storage tanks when they are installed.
There are some very nice PLC's with built in displays that would seem to be a good choice for what you are doing.

What PLC are you using? I've done a lot of work with PLCs, and they are a great solution for a class of situations. There are a few things I wanted that I couldn't find at a reasonable price 4 years ago. The world keeps changing and products get better, but I think these still apply:

1) Inxpensive analog inputs. I'm currently running 14 channels of analog input at around $20 per channel including the sensors and cabling.

2) Extensive datalogging. I log all inputs and outputs every 30 seconds, and have all that data for the last 3 years.

3) Programming flexibility and options. I use the full range of Linux tools, although I'm developing a simple web-based option for non-techie users. It's open source, so I have all the code for everything, and can make any changes or improvements that I want.

4) Full network capabilities. I have a built-in Apache web server, telnet, smtp, nfs, sql, and ssh. That allows complete control from any remote location.

5) Low power consumption - under 5 watts.

6) Combination of scalability and compact size. With 16 analog in / 32 discrete out / 32 discrete in it fits in a 10x12x6 enclosure

7) Low cost - I'm a congenital cheapskate. Total component cost for everything - hardware, software, components, sensors, and cabling - is under $700, even including an industrial enclosure.

Last time I looked, I didn't find any commercial offerings that came close. That having been said, it's overkill for simple situations. I think where it starts to make sense is more complex installations with storage and/or solar, where you're trying to implement more complex control logic.

The other thing I'm hoping to accomplish with the NFCS is a controller that's simpler for people who might be intimidated by understanding and programing a PLC.

However, I'm also a fan of simplicity. My most often recommended system solution for wood heat with storage only requires addition of a circulator, and aquastat, and two relays to add storage to an existing system. No controller at all. There's certainly a middle ground where a PLC may be the right solution.
 
My goal seems to be a lot different then yours. I wanted to set up a system that would be completely invisible to my wife so when she turns up the heat she has heat and at the same time minimize the use of the oil boiler. So far it is looking pretty good.
I have worked with a lot of equipment were a lot of money is spent on data collection that never gets used so I tend to shy away from that approach. Data logging is great if the data gets looked at but so much just sits on a hard drive for years and then gets deleted.

I'm using a Automation Direct DL105 PLC. It's cheap, I just looked at the web site the price seems to be a little higher now, starting at $159. It gives me 10 inputs and 8 outputs and I programed it in 45 minutes. Right now I'm using 7 inputs and 5 outputs so it seems to be a good fit. The programing software is free for programs under 100 words. I know direct automation isn't consider a serious controller but it works well and it's made in the USA!

The other one I was considering was a Unitronics, they are very compact PLCs with a screen that could be set up very easily as a control panel. They have a lot of units with analog inputs and a lot of communication options. The only model I know a price on was the V350-35-T2 at around $700. This unit has a real nice screen but I know there are cheaper units. You can download the complete program software for the logic and the screen for free as well.

Mitsubishi Electric also makes some very nice small units, I've haven't checked myself but I hear they cost around $400.
 
kgryder said:
My goal seems to be a lot different then yours. I wanted to set up a system that would be completely invisible to my wife so when she turns up the heat she has heat and at the same time minimize the use of the oil boiler. So far it is looking pretty good.

We're on the same page there. The room thermostat is a pretty compelling user interface in terms of ease-of-use. My intent for my own installation is to have it be as unobtrusive as possible to the family. However, I have a second goal in trying to understand the system as deeply as possible and figure out how to obtain the best performance.

I've had a lot of interest in my controller and it's my hope that it will fill a niche for those who need (or just want) capabilities beyond what PLCs offer. If you haven't done so, click the 'voyeur' link in my signature. I lit a fire a while ago, and it will show the last two hours. Feel free to play.

For those who want to reach in and play, here's a link to a version of the controller web interface that allows you to edit system constants (setpoints and deadband). I've got the light set up to heat the main floor sensor again. Please don't try and break it, but feel free to look at how it works. Use the 'Refresh' button to get real-time data. Check the 'Edit' box and click Refresh to get edit mode.
 

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