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From a previous post by Tesla I see that he uses self built controls using the Arduino system components.
Having done a small amount of reading up on these things they seems to have quite a bit of promise as regards replacing or substituting original control sets.
If anyone can expand on these I would be most interested especially leaning towards mini-splits and 4 pipe fan coil units.
I am just starting to configure an Arduino Mega for controlling the heat pump, liquid pumps, back up boiler and 3-way liquid diverting valves. I must admit to being more of a programming ludite than I would like to be though. Must be the ADHD, haha
Hi Brian & Mike
I bought the Arduino Mega too (just to play with). I think the Mega might be more than needed for a split and there are smaller (IO) Arduino's at half the price (AUD$60). I will learn the new programming in the next few months - it's new to me too. There are many bits of programs in libraries on the net for free. One limitation is the amount of AO available as most of the AO is going to be used for comms. I found a China supplier which is much cheaper for the external boards (BOBs) or Break Out Boards. http://yourduino.com/sunshop2/index....t_detail&p=156 is where I got many sensors and 8xDO BOBs. There is not too many HVAC programs yet but a few for domestic purposes. For me this is the best thing since sliced bread.
Video link http://documentaryheaven.com/arduino-the-documentary/ there are many others.
A few pics of the parts and controller (put on hold for a study course)
Attachment 10078Attachment 10079
Hi all
I am playing with my Arduino (sounds bad!) to communicate on Modbus RTU and use Monitoriza as the SCADA.
Its the family and work getting in the way of my projects :p
I will keep you updated and it would be great to be able to share sketches on this forum.
Long live open source!
http://arduino.cc/en/
Link above for anyone wanting to find out about the Arduino, programming is in Arduino language which is based on C, but is simplified.
The big issue for me is PID and as for AO, you might be able to use a shift register to share AO pins. I'm not sure about this as I just thought of it. I really have a block when it comes to programming so it will take me time to get anywhere with it.
Also, max current for relays is only about 20mA so if you want to be running anything direct you have to be careful or get into transistors etc and then it gets complicated.
Must admit that it has been a good 25 years since I did a C++ course so I have some serious brain storming to be done again, a bit like you Mike.
This http://yourduino.com/sunshop2/index....ct_detail&p=60 should do the AOs and your right MH about the shift register. Thinking about it we don't really need anything fast for the AOs in HVACR applications. But all connections should have opto isolation and there is a limit of total current for all 70 IO ports hence using BOBs with separate power. Like you Brian and MH I learnt Pascal programming back in 94 so it's like relearning. And I wanted to use the fast IOs (I think P0 to P13) for comms and smart sensors. The smart sensors can be daisy chained with two wire connection but the limit of power would require three wire daisy chain. This post has inspired me to go hard for open source.
I just ordered some relay banks from "yourduino" but I didn't think of the FET stuff. I wanted to use PT1000 thermisters for sensors but Arduino seems to favour the "1 wire" systems for sensors. More wiring needed. Variable speed pumps and 0-10vdc for modulating valves are on the wish list as well.
I went to a place called DeVry Institute of Technology (owned by the old Bell and Howell projector company) in the early 80s for electronics but I hated programming so I promptly forgot it all. Wish I hadn't forgot it now.
MH just like me I did the big order of sensors etc through the same and didn't think of the FET stuff. It is going to take a little research for the best method and I am leaning towards smart (communicating) sensors with separate power (battery or wired). I rechecked the programing today and it looks like Java based which is similar to C and Pascal.
They state that it is based on C++ with some things to make it simpler for the programming challenged idiots like me. It seems some people are using the Arduino as a production board, which I would like to do if it works out, so finding a way to reduce the components to a minimum is important. That said, if you find an easy method to do the sensors, let us know. What sensors did you order?
I downloaded some software from http://arduino.cc/en/main/software which states in the first paragraph that it is written in Java. I have seen other software that is C based but that may be an older version for the Arduino.
The sensors I purchased from China are
Sensor Shield - for ease of connection
10k Thermistor x 5
DHT11 Humidity and Temperature Sensor
Motion (PIR) Sensor Module
Waterproof DS18B20 stainless steel encapsulated temperature sensor x 2
DHT22 High Accuracy Humidity and Temperature Sensor
PhotoResistor type 5516 5-10K (10 ea) x2
433 Mhz 3 pin Transmitter-Receiver pair
LCD Display Blue 2004 (20x4) IIC, I2C, TWI
From Jaycar I got the IR Temperature sensor which has these numbers on it LN:2222 ZY temp, I think the latter is the manufacturer and they have many models. This is the awesome one I think as it can be networked on daisy chain up to about 30. Another advantage is it measures a ratio of 1:1 beam so in an office it would measure an area of 2M diameter - getting a more accurate average space temp. It was not cheap from Jaycar (freetronics) but I'm sure it will be a fraction of the price from ZY temp if you ordered 10s or 100s.
If only there were like 50 hours in a day I could get stuck into testing it.
I showed a few controls companies theses products, one is very interested and the other I got the impression were very threatened by it.
i stand corrected on the C++/Java programming. Did you get the above stuff from "yourduino"? I bought some material from them as well, but I forgot what... lol
Why complicate things with CC+ logic. Been there once and got totally stuffed up.
MH I got the stuff from yourduino and need to make another order cause I forgot stuff too - but will wait till I have a total list next time and have done my homework properly.
Magoo I have played with a lot of line code an many control systems and they are all very similar. On top of that there are several libraries of lots of application code available free on the net so it's a case of copy and paste the modify for parameter limits. There is also a forum for it and like this one it is very helpful. In saying that I am thinking of doing a Java course when I find the time and can afford it. Best of all it's free free free. This allows an affordable approach for creative minds like us to get it done and make it work.
MH This http://playground.arduino.cc/Main/Ba...orEspresso#pid is an example of PID temp control, old and I know there are many more newer and application specific.
OHH this is getting good. Where is the free Java course, which I assume is on the net?
I have to wait for the stuff to come from China too. I did get a sensor shield and a relay bank suitable for Arduino. Now I want to find out how to do the shift register on the SENSOR INPUTS so I can use a smaller unit than the MEGA.
Sorry to get your hopes up there MikeH but the Java course is not free it is the software that is free. In saying that what a great idea I will look on the net for a free Java course online over this weekend.
Quick search for FREE tutorials and came up with this one -->
http://www.homeandlearn.co.uk/
Sikh and ye shall find
Hello.
When you want to replace with Arduino a split pcb that cannot be found, how about the IR remote controls ?
Hi Yuri you could use something a little flash like this http://www.refrigeration-engineer.co...hlight=arduino
or Im sure there is a generic remote for it on the Arduino forums but I think the above one is more exciting.
Hello. I am afraid the user from Finland appeared to boast, and dissappeared - I just googled for "IR module
KM08ARSM" but have found nothing apart from a list of codes he was talking about.