Well, you're thinking like a businessman. The next question is, how big is the market? My suggestion would be to make it the way you describe as a test unit.
But think about it, once the turbine is working as designed, it just does its thing. I would avoid bells and whistles except as an add on option.
All your specs look perfect for the field of applications we are working on. No one here is working on the MEGA VAWT.
Someone might argue 400 watts is low, but the reality is that it is plenty high enough for anything other than bigger commercial VAWTs.
I will be your first customer for the non-bells and whistles version. Once I know what it does I probably wont monitor so I don't need LED's or pigtails, or computer ports.
Just control, and braking.
Price? I do this sort of stuff for people. The truth is if I don't price items high enough I don't want to be bothered. Its not about cost and then double. Its about my time.
If its just components and pc board and instructions, I'd say, cost plus $50. Try keeping it under $100, or $175 for bells and whistles.
I could live with using the meter to check to get the cost down. I also am not worried about turbine overspeed unless it would hurt the controller. I've had some pretty fast winds for short periods and the turbines seem to do just fine in them. I did get up to around 25 Amps in them though for about a minute.
In case anyone is wondering I haven't fogotten about the intelligent charge controller. I see at least two people who are looking for / need one. That's Lynx and Wibolator.
I have the design complete and simulated, I have most of the parts, and I just need to route a board and build it up.
The problem is I'm uncertain about the features and price point.
The specs are: Max turbine voltage: 75v (100v if you sacrifice being able to measure turbine current.) Max turbine current: 24A+ per phase (12A diodes used less than half the time), Max battery voltage: 75v Max current into the battery (per channel) 30A Max wattage for a 12v battery system 400w. Max wattage into a 24v battery system 800w.
The price including the microcontroller board, PCB and parts (you put it together yourself) would be about $160.00
What is does:
1) Peak power control of the turbine. (Keeps your turbine from stalling, and has it run at it's best operating point no matter what the winds are.)
2) Maximizes use of low winds if you wind your alt to put out high voltage. (In higher winds it reduces the voltage by changing it into current.)
3) Safey monitor, puts the brakes on the turbine to keep it from going too fast in high winds.
4) Provides monitoring functions like Derek's system.
So the question is, is that too much money? By reducing the specs the price can be reduced. For example if we get rid of the microcontroller board and you just get a black box that you put turbine power in and get battery charging voltage out. It would be cheaper by about $60.00, but you wouldn't be able to tell what power was being produced without measuring with a meter.
Also if the current / voltage / power limits can be reduced, that makes the parts cheaper.
My plan is to get a turbine up in the air, then build this circuit or something like it , but I'd like to build something people would use and can afford.
Anyone have any input?
Maybe the better way to go is tell me what this component should cost and I'll tell you what I can build for that. RIght now I just know Lynx's estimate for a 6er is $45.00 or so. This is more capable and more efficient but does it need to cost about that much?
Yes, I've used XBee, they can be driven using the microcontroller UART, so are easy to use. Good wireless distances are also possible (<=1km), although you need to check your local radio laws for tx power settings.
Bryan
Not used the arduino system, but lots of people seem to love it. It looks like a good system for the beginner.
Not sure whether I'm reading too much into your post, but my UI (eUI for the PC) over ethernet is only compatible (protocols) with my microcontroller software. You will not be able to use the eUI program with your own turbine solution (unless you duplicate all of the protocol interfaces). Therefore there doesn't need to be an ethernet interface for your own solution, you can choose any comms system. You will also have to write the software for the PC side to talk to your microcontroller over that interface.
Normally, for using XBee : there will be one XBee + microcontroller at the turbine, and another XBee + microcontroller in your home (anywhere - it's wireless!). Then you can decide what UI you want (LCD/PC) and connect to the indoors microcontroller. No wifi required with this approach.
I've been looking at the Arduino boards. There is a lot of open source stuff available as examples and the programming looks simple. They use Atmel microcontrollers, and I've used those before so that is nice. The basic board with an ethernet shield costs about $70 and you can get an adapter for the XBee wireless unit. I'm still looking to see if the XBee is compatible with a wireless-G router; I don't want to re-do my whole house. I'm guessing that I will go with the Linksys bridge. My birthday is coming up. :-)
I was also looking at WizNet products. They have a nice board with an Atmel microcontroller and an ethernet port for a good price (about $45) but I think you have to buy the development board to program it (about $100 - although that does include one of the ethernet/microcontroller boards). Programming looks a little more challenging than with the Arduino.
-- Edited by Caleb on Monday 8th of March 2010 03:04:40 AM
Install a wireless router/bridge/access point to the monitoring device outside and send the data to another wireless router/bridge in the house?
Power is going to have to be supplied to the outdoor unit. The wireless unit runs on AC so you would have to have convert the output from the turbine to AC to power the wireless unit and a battery. Then what happens when the wind is calm for a few days or you just have low wind?
Jerry
You could install the wireless router outside, or inside where your battery is. The point is you don't have to string a cable through your house, just because you have a wired network device somewhere far from the rest of your computers.
The linksys units run off of 110v with a wall wart. The actual input to the device is low voltage DC. (5 of 6v I think). I used to run a wireless ISP, and I had several of those things running off of a battery at a remote tower.
In the end, I think I agree with you, I'm just going to run an Ethernet cable with the other cables to my mill. Although everyone should remember lightning protection on the Ethernet. If your cable gets hit, it could do a LOT of damage to things on your network.
Oh I see. If you have an outdoor outlet you could get a pair of "Ethernet over AC line" convertors. I have a pair I use to get internet to my shop. They work very well, I think I bought a pair 5 years ago for $60.00 and the speed is about 80 mbps. I see them in the local"Best Buy" stores. One in the outdoor outlet and one in your house near your PC, plug in the cables, magic.
Install a wireless router/bridge/access point to the monitoring device outside and send the data to another wireless router/bridge in the house?
Power is going to have to be supplied to the outdoor unit. The wireless unit runs on AC so you would have to have convert the output from the turbine to AC to power the wireless unit and a battery. Then what happens when the wind is calm for a few days or you just have low wind?
Jerry
You could install the wireless router outside, or inside where your battery is. The point is you don't have to string a cable through your house, just because you have a wired network device somewhere far from the rest of your computers.
The linksys units run off of 110v with a wall wart. The actual input to the device is low voltage DC. (5 of 6v I think). I used to run a wireless ISP, and I had several of those things running off of a battery at a remote tower.
In the end, I think I agree with you, I'm just going to run an Ethernet cable with the other cables to my mill. Although everyone should remember lightning protection on the Ethernet. If your cable gets hit, it could do a LOT of damage to things on your network.
Install a wireless router/bridge/access point to the monitoring device outside and send the data to another wireless router/bridge in the house?
Power is going to have to be supplied to the outdoor unit. The wireless unit runs on AC so you would have to have convert the output from the turbine to AC to power the wireless unit and a battery. Then what happens when the wind is calm for a few days or you just have low wind?
I think it would be easier to just run the cable. More reliable and less trouble thats for sure.
There are little devices that will convert wireless to Ethernet. They are used to connect desktop computers to wireless networks. One of those plus the microcontroller circuit would probably work.
So as I understand it, you want your PC (in your home) to wirelessly talk to 'something' (data acquisition system) on or near your turbine, that will give you turbine data to display on your PC.
This is exactly what the performance monitor tool in this thread does - apart from the wireless bit.
Microcontrollers of all types (PICs ARM ...) allow you to do lots of things better and cheaper than adding a 'whole' PC. They give you lots of comms options UART, SPI, I2C, ethernet ...
For a bespoke solution, you will have to decide what type of comms to use, and write the software for rx and tx each way. Then integrate it with your UI on the PC end. This is non-trivial.
Wireless solution - could be Wifi or rf (e.g. XBee).
You don't need to have a webserver. Although as a point of interest, many microcontrollers now have example embedded webserver software, so that you can access some basic webpages (containing your data) via the PC browser. [wired]
What approach to adopt is completely down to you, there are many solutions. If you are new to software I would choose a microcontroller (e.g. PIC), and start writing some C code, then gradually build up to wireless comms.
My solution in this post is generic, in that it allows you to modify the open-source C code so that you can control/monitor any data you want, which automatically changes the PC (UI) to your own, but will not allow wireless comms at this time. Although incorporating a Wifi chip could be a future option.
I think you need to supply a schematic of what you want to do.
Your approach seems complex and expensive.
You can setup your webserver on your vista PC, why buy another one? A webserver is just an application like excel is an application, you can run multiple applications at the same time on your PC.
Apache http webserver is the best around and is a free download http://httpd.apache.org/
Do you really want a webserver?
A 'gadget' or UI (user interface) can be a program (desktop application) that runs on your operating system (e.g. vista) - just like excel/word etc. They don't need html.
A UI can be web application that runs over the internet, which just means that you can run your UI from any PC anywhere on the internet. For this you would need a website and webserver and an html application for others to use. It does exactly the same thing as a desktop app, but allows remote use over the internet.
The performance monitor described in this post is a desktop application, that will display current (and voltage and power and speed) on your display every second. It doesn't use a webserver.
My Vista desktop is on the opposite end of the house from my data collection point. I thought it would be nice if I could send the data through the wireless router instead of running a cable and drilling holes in the walls. I was looking at the luminarymicro microcontroller like you had but it still would need a power supply and some wireless device. After seeing a video on how to put together a computer, I figured it would be just as easy for me to assemble a cheap computer, load it up with free software and start from there.
A couple things I don't know about software and networking (among many): How do you get two applications running on a computer to talk and share data? And do I need a web server to receive calls for data from my data acquisition system over a network?
I would like to have a "gadget" on my Windows Vista desktop that shows the current from my windturbine and solar panel every 5 seconds or so.
...y
I'm not sure what is required to get the data from the DAQ to the web server software. Should that be possible with a bit of C++ code? Can anyone point me in the right direction or am I completely off base with this set-up?
I think you need to supply a schematic of what you want to do.
Your approach seems complex and expensive.
You can setup your webserver on your vista PC, why buy another one? A webserver is just an application like excel is an application, you can run multiple applications at the same time on your PC.
Apache http webserver is the best around and is a free download http://httpd.apache.org/
Do you really want a webserver?
A 'gadget' or UI (user interface) can be a program (desktop application) that runs on your operating system (e.g. vista) - just like excel/word etc. They don't need html.
A UI can be web application that runs over the internet, which just means that you can run your UI from any PC anywhere on the internet. For this you would need a website and webserver and an html application for others to use. It does exactly the same thing as a desktop app, but allows remote use over the internet.
The performance monitor described in this post is a desktop application, that will display current (and voltage and power and speed) on your display every second. It doesn't use a webserver.
I would like to have a "gadget" on my Windows Vista desktop that shows the current from my windturbine and solar panel every 5 seconds or so.
From what I've read, the gadgets use html code. So I think I can write a bit of code to request data from a web server and display it on my desktop.
To make a web server, I've been thinking about getting a small PC with a wireless connection from Pricewatch.com (approx $180 w/o monitor) and loading it with Linux and some web server software like Boa. Then attaching a data acquisition module from Dataq (approx $50) to convert analog signals and provide digital inputs for my solar / wind system. I have a wireless router, so I think I could set up a LAN with my desktop computer.
I'm not sure what is required to get the data from the DAQ to the web server software. Should that be possible with a bit of C++ code? Can anyone point me in the right direction or am I completely off base with this set-up?
I would like to have a "gadget" on my Windows Vista desktop that shows the current from my windturbine and solar panel every 5 seconds or so.
...y
I'm not sure what is required to get the data from the DAQ to the web server software. Should that be possible with a bit of C++ code? Can anyone point me in the right direction or am I completely off base with this set-up?
I would like to have a "gadget" on my Windows Vista desktop that shows the current from my windturbine and solar panel every 5 seconds or so.
From what I've read, the gadgets use html code. So I think I can write a bit of code to request data from a web server and display it on my desktop.
To make a web server, I've been thinking about getting a small PC with a wireless connection from Pricewatch.com (approx $180 w/o monitor) and loading it with Linux and some web server software like Boa. Then attaching a data acquisition module from Dataq (approx $50) to convert analog signals and provide digital inputs for my solar / wind system. I have a wireless router, so I think I could set up a LAN with my desktop computer.
I'm not sure what is required to get the data from the DAQ to the web server software. Should that be possible with a bit of C++ code? Can anyone point me in the right direction or am I completely off base with this set-up?
I have 50, 100 and 130 amp versions for H2 electrolyser applications but have yet to hook them up.
Feed it 5 volts and it give a milliamp signal proportional to current flow
Turtle
Nice sensor, but it looks like it's been discontinued and Digikey doens't have it in stock. I used a 10mohm sense resistor and a max4080. This sensor would be a little nicer because it doesn't need the 10mohms in the line. But I think it would take more board space (looks to be about 2cm x 1cm), which is in short supply right now.
Sounds like a good idea, could it be expanded for more current carrying capacity ? I would think a dump load would be a must, why not make use of the energy after the battery's are full, could use the dump load for something, hot water preheat perhaps.
Do you have a turbine that makes more than 24 amps?
The answer might be found in the willingness to develop somehting that very few might ever use; the beauty of which being that it will be available for all who want to jump in (as long as the parts list is current).
Right now, the whole 'writing of code' thing is over the turtle's haid, but I can surely assemble components and copy / paste what others have laboured over.
Sounds like a good idea, could it be expanded for more current carrying capacity ? I would think a dump load would be a must, why not make use of the energy after the battery's are full, could use the dump load for something, hot water preheat perhaps.
I see that there was an earlier topic regarding MPPT (last year), where Steve offered to make a system for the community.
There was a luke-warm response then, and the project was put on the shelf.
Now here we are Today, we already have a performance measuring system to accurately log the performance of our wind turbines. Steve has had the idea of building upon that, and incorporating an MPPT with it, so that we can not only measure our turbine's performance but improve it as well and make more power.
This will be a non-profit project for the community, that will involve a considerable amount of effort. I'm happy to help Steve realize the project, and help the community build better wind turbines.
So the question is : What are you prepared to do?
Are you prepared to spend a few minutes to make a post. For or against. Maybe :-
What is an MPPT Why do I need one How do I connect it to my turbine How much more power will my turbine make with it Isn't it really complicated to setup and use If I wanted one I'd buy a commercial one I'd like one but it must be able to do a) b) & c)
If you have ANYTHING to say, now is the time to say it ...
Max turbine voltage: 75v (100v if you sacrifice being able to measure turbine current.) Max turbine current: 24A+ per phase (12A diodes used less than half the time), Max battery voltage: 75v Max current into the battery (per channel) 30A Max wattage for a 12v battery system 400w. Max wattage into a 24v battery system 800w.
The board includes a very efficient 3 phase rectifier so that the turbine output can be run directly to the board.
Values that are monitored: Turbine V, turbine current, battery V, battery current, turbine RPM, wind speed. (Compatible with the home built anemometer and the $50.00 purchased one.)
Simulated Efficiency per channel (12v battery system): 25 watts: 96% 250 watts: 90% 350 watts: 86% 400 watts: start to drop significantly. 400 watts should be for unusually high winds, not the norm.
*Efficiency was simulated using an inductor made from #18 wire (2 strands), and 2 caps worth a total of $10.00. It is possible to spend much more on caps and bring the efficiency up. Efficiency also mostly depends on current, so 24v, and 48v battery systems will have a higher efficiency at the same wattage.
There are other practical limits to the board. The connections for the turbine, battery are big pads with 1/8" holes. I think that will fit a #9 or #10 wire. (#9 might be pretty tight) If you have two channels producing 30 amps each, that will be too much current for that size wire. Also the traces on the board will probably be glowing red hot. :-)
I'm working with board dimensions of 3.8 x 2.5 inches so I can use the miniboard service from ExpressPCB. For prototypes and small quantities that seems to be the least expensive way to go.
In order to fit on such a small board, there will be two 'off-board' components per channel. One is a high voltage cap (about 1 inch diameter and 2.5 inches tall.) The other is an inductor, about 100 turns around the cardboard from the center of a roll of toilet paper. Large pads are provided to run wires to these components.
Cost Estimate: Microcontroller board: $70 My bare board: about $20 (but they come in orders of 3) Parts: $55.00
Total for one turbine: $145.00
However I have hopes of squeezing a second MPPT on the same board. So hopefully for another $38.00 in parts the board could handle a second turbine or solar panel system.
In that case the total cost is $183.00 or $91.00 per turbine. I think that's getting pretty reasonable for an MPPT with network capability. Would anyone be interested in the dual version or that a waste of my time?
All price estimates are for build it yourself, no profit on my part. In some cases minimum order quantities will force you to pay more, because you will get extra parts. I don't know what my long term plans are for this, maybe I would put together kits so that parts could be ordered in bulk. But I'll cross that bridge after I have a real working unit.
I'm about to start board routing to see if I can squeeze in the second channel.
I had considered incorporating a brake circuit or dump load, but that's not currently in there. Is it needed? Is it okay to let a turbine free spin if the battery is charged to full?
Softstuff and I are just starting to talk about what software features we would want / need to control and monitor this system.
Feedback is welcome and appreciated.
-- Edited by sjh7132 on Sunday 21st of February 2010 05:53:31 AM
-- Edited by sjh7132 on Sunday 21st of February 2010 06:03:44 AM
-- Edited by sjh7132 on Sunday 21st of February 2010 06:34:03 AM
-- Edited by sjh7132 on Sunday 21st of February 2010 06:46:21 AM
-- Edited by sjh7132 on Sunday 21st of February 2010 07:05:06 AM
Trying to stay off the hardstuff as much as possible ...
Could you describe 'spikey' what magnitude to the normal - frequency of occurrence ...
Is this from your first turbine in the video (the one with the wobbly stator), I wouldn't be too surprised if you're getting a few spikes!
What is your system setup - turbine, circuits ...
Happy to do a test for you, when I understand what I'm doing ...
I'm designing a PPT controller for turbines, and the switching of the current on and off through the inductor introduces some microsecond long current spikes across the sense resistor. I'm trying to get the 4080 to get the 1ms average current instead of possibly reading those spikes.
I'll post full schematics in a day or so. If you want to PM me your email I'll give you an earlier peek.
This is an example:
In this case the turbine is producing 27.3v and 1.0A
The battery is receiving 14.2v and 1.85A
The spikes are high, but of so little width that they are insignificant, yet they could mess up the measurements.
Don't worry about trying the circuit, I've simulated it, and think I have something that will work.
Just been thinking about system setup. Not sure where you are with yours, but casting my mind back, I had some instability issues with the circuits at first because of a bad ground signal. This was solved by grounding to the building earth. Everything was fine after this.
Apart from one thing, when another appliance on the building circuit was turned on/off - sometimes got a single BIG spike - which didn't happen if building earth was removed. Some kind of EM interference I suppose.
Trying to stay off the hardstuff as much as possible ...
Not sure what you are trying to do, if your turbine produces spikey outputs, then you'll see spikey outputs from the Sense circuit. If your turbine produces smooth outputs, then you'll see smooth outputs. That's kind of the point, real performance of your turbine - for better or worse.
Could you describe 'spikey' what magnitude to the normal - frequency of occurrence ...
Is this from your first turbine in the video (the one with the wobbly stator), I wouldn't be too surprised if you're getting a few spikes!
What is your system setup - turbine, circuits ...
Happy to do a test for you, when I understand what I'm doing ...
Hey Softstuff, would you be willing to do an experiment for me? (Even if it involves some hard stuff? :-)
I'd like to filter the input to my 4080 to remove some current spikes. If you still have yours in a breadboard would you be willing to try this circuit and see if the 4080 still reads accurately?
I found a solution to the sizing problem. There will be a few components, like the main transistor and cap, that you can either populate 1, 2 or 3 of depending on how much current you need to handle.
I'm starting to back off on the 500w idea. 500W into a 12v battery is 41 amps. Into a discharged 12v battery at 10v it's 50 amps. That's a LOT of current. In theory you'd use #5 wire for that. I think 500W may be for 24v systems and above. But we can see what happens if anyone ever makes a turbine that can produce it.
So, honestly is anyone producing more than 100W on a regular basis from their turbine?
Keep it simple and cheap for a first effort. Definitely allow for 24V battery system. Amps - who's making more than 5A regularly? so 10A max should be fine.
There are probably two types of builders anyway : a) first-timers and new designers - will only need low power systems for trials. b) power producers - who probably have their own system anyway, or require a different setup - which could be done later.
I'd stick with a) to start with.
If you want to include solar panel current measurement too you might want at least 250W capability. The Luminarymicro uController has 10 bit ADC resolution. For reference, a 10 Amp sensor could resolve 10 mA of current.
-- Edited by Caleb on Thursday 11th of February 2010 02:49:57 PM
I'm not on a regular basis. I am still changing some things though but with the size I'm running now I don't see getting that much most of the time with the height I'm at now.I just went to 3 blades on the 2 blade on the dock,but need to get the airgap adjusted right again there. I'm limited by town ordinances on towers. I'm in the A catagorie, started last spring.
-- Edited by wiboater on Thursday 11th of February 2010 12:48:21 PM
So, honestly is anyone producing more than 100W on a regular basis from their turbine?
Keep it simple and cheap for a first effort. Definitely allow for 24V battery system. Amps - who's making more than 5A regularly? so 10A max should be fine.
There are probably two types of builders anyway : a) first-timers and new designers - will only need low power systems for trials. b) power producers - who probably have their own system anyway, or require a different setup - which could be done later.
I have a PPT turbine controller board (that mates with this controller) working in SPICE simulation. I'm about to start the actual board design and layout.
One thing I need to know is how to size the transistors and diodes. Ideally stators would be wound to put out a voltage that's 3x or more of the battery voltage so that the controller has some freedom to pick the best operating point. Plus then it can still extract power in low winds.
So my questions are:
1) What maximum (open circuit) voltage should I design for? 70v? 150v? 200v?
2) What maximum current from the turbine should I design for?
3) What kind of turbine wattage should I design for? 250w? 500w? 1KW?
It is possible to design for worst case, 200v, 1KW, but then we sacrifice efficiency, plus transistors that can handle high voltage and high current are big and expensive.
Right now with my semi-random selection of components I get a little better than 90% efficiency in simulation.
If nobody weighs in with preferences, I'll probably go with 200v or 12A max from the turbine, 500W total power limit. If this is oversized, let me know and I'll scale it down for more efficiency. (and less cost!) Seriously, does anyone have a turbine making more than 200 watts?
The system would be good for 12v or 24v batteries with the built in power regulator. If you want to supply your own power supply, then the battery voltage could go up as high as 48v
I've already open-sourced the first demoUI microcontroller software (desktop dir), so you can make your own assets whenever you want. If you need any guidance, let me know.
Doesn't matter if you're not going to develop your own software.
If you want to write some software, then each manufacturer imposes their own restrictions on their own development IDEs and compilers.
I use codesourcery, because it's a free download and no restrictions. I use eclipse IDE for the same reason.
Oh I would probably end up writing some software, or modifying yours if you post the source. :-) I'll order the same thing you use so we are compatible.
dereksoftstuff wrote: Perhaps $20 -> $30 for rest. pair of bearings was the most expensive part - about $6 for pair. Ball****s are $1 each wow great value.
Bearings are always a pain to get for a project, a good source of small bearings is the Sports store. I buy the roller skate bearings, when on sale you can get 16 for about $16.00, otherwise around $25.00. If you want to go cheaper, there is always the kids rollerblades :)
Parts cost $ - well that probably depends on where you are starting from. After seeing some of the great building skills on the forum (with workshops to die for), most of the parts can be found. Perhaps $20 -> $30 for rest. pair of bearings was the most expensive part - about $6 for pair. Ball****s are $1 each wow great value.
However, build cost for me was over $60, mainly due to trying a few different things, and also having to buy a 10mm die-cutter.
But it was a fun little project, and my workshop is a bit healthier now.
If you buy an anemometer, we need to make sure it can be integrated into the existing system. So need to check the digital output it generates. Number of shaft magnets etc. I don't think there's anything that can't be sorted with a bought one.
Additional features (assets) - I'm sure there could be lots of these, and they are ALL possible now with a microcontroller. Different 'products' (firmware builds) can easily be made, and we could pick the one we want.
I think we have to walk a bit before trying to fly ...
This is new stuff, and a few builders will need to adopt it, test it out and make some videos to show whether this is a good way to go.
We can build our own anemometers (see next video) and I'm not a mechanical engineer ! :-
a) for a lot less $
Your anemometer looks very nice, but are you sure it can be built for less than $55.00? It seems that after you buy all the hardware, tubes, toilet parts, magnets, sensor, cutting board, etc you could get yourself up to $55.00 pretty easily with a bunch of $3 - $5 parts.
I think the purchased model isn't looking so bad if it works.
It seems with the addition of a few more parts this measurement system could actually become an intelligent charge controller that could let the turbine run at one voltage and the batteries charge at another. (Peak power tracking). And it would still have some nice monitoring features.
Would there be interest in that version?
Derek, would you be willing to add some features to the firmware to send data to a D/A to set the turbine voltage?
-- Edited by sjh7132 on Friday 5th of February 2010 03:50:25 PM
Good idea, I was thinking I'd have to do something bespoke. The crucial point is the power supply, since having a reliable local supply is a necessity in remote installations.
The USB connection is only needed for 2 things :-
a) LMI programmer uses it to load firmware to board (not done often - but needed for new releases)
I'm considering designing a board to mate with this system, that would have the voltage divider, current sense circuit, and a power supply so you could run the microncontroller off your batteries. (If the firmware will handle that.)
If the bare board sold for $10.00 + shipping, how many of you would be interested?
The alternative would be to use a breadboard or wirewrap sockets and perfboard. I think both options would cost about the same amount of money.
Derek, if you already have such a board in progress let me know and we will all use yours.
