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A watering controller that can be home networkedby drj113 on September 14, 2010

Table of Contents

A watering controller that can be home networked . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Intro:   A watering controller that can be home networked . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Step 1:   How do you drive the solenoids? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

File Downloads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Step 2:   Making the board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Step 3:   Soldering the components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

File Downloads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Step 4:   Programming the micro . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

File Downloads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Step 5:   Testing and programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Step 6:   Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Step 7:   PCB Artwork . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

File Downloads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Step 8:   Where to now? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Step 9:   DC vs AC Solenoids. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Related Instructables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

http://www.instructables.com/id/A-watering-controller-that-can-be-home-networked/

Author:drj113I have a background in digital electronics, and am very interested in computers. I love things that blink, and am in awe of the physics associated with makingblue LEDs.

Intro:  A watering controller that can be home networked

A couple of weeks ago, I published a great little controller module that provided 6 relays able to be controlled from a computer via a network.  After I published it, I got tothinking that the same basic design, with a couple of changes could be pressed into service as a garden watering system controller.  So, I got to work, modified thedesign, and here you have it...  A sprinkler controller that runs by itself, that can be programmed and monitored from your computer via your home network.

This specific version of my sprinkler controller obeys some simple rules that have had to be implemented where I live.  I live in Australia, or more specifically in an inlandregion called the A.C.T, where our government have implemented an ODDS and EVENS watering regime.  Under the system if you live in an odd numbered house, youmay water on an odd day of the month.  Likewise, if you live in an even numbered house, you may water on an even day of the month.  Everybody may water on the31st.

This system, along with the mandatory replacement of sprinklers for dripper systems has sucesfully reduced the load on the cities limited inland water supply so thatmore drastic measures were not required.

Unfortunately, this system was unable to be implemented on my commercial water controller, it wanted to water on a Monday, or a Wednesday, so I was breaking thelaw, and subjecting myself to a potential fine every other week...  So I had to build my own controller.

This instructable shows how I built it - there certainly is enough detail shown so that you can make it yourself if you are enthusiastic, and willing to give it a go. 

Update:  the full source tree for the Kicad project is located here

Image Notes1. The old controller - Yep I am replacing it!

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Image Notes1. the old controller supplied 24VAC - which is a bit much for my new board - So Iam temporarily running 12VDC to the board till I can replace the transformer in theunit. Yep - The solenoids run fine on +12V2. I have to modify the case - for some unknown reason the original manufacturerdidn't think of ading a socket hole for an ethernet connector!3. I only have a couple of zones in use at the moment - but that will change4. Yep - I have to re-tag the dryer... one day

Step 1: How do you drive the solenoids?

The sprinkler controller is built on the base of my Adruino Ethernet controller.  The Arduino ethernet controller provided a basic network connected ATMega328 chip, andhad a number of spare I/O lines. 

I extended the PCB design to provide 6 solid state outputs, each able to drive +12v at 300mA, which is enough for a watering solenoid.

Each solenoid output is driven from a NPN transistor, as shown by the attached picture.  To turn on the transistor, the port pin is simply driven high.  I decided to useindividual transistors, as they cost $0.03 each, and if they are destroyed, they are individually replaceable easily.

There is also a DS1302 RTC chip on the PCB - it is simply driven directly off 3 pins of the Arduino.

The whole board is driven by a 12VDC plug pack transformer.

It is not sensible to describe the full details of the Ethernet controller here, just check out the Arduino Ethernet controller (which is basically an Arduino and aNuElectronics shield) for info.

You will find the full schematic diagram attached as a PDF.

File Downloads

Sprinkler-Controller-Schematic-v1.pdf ((595x842) 82 KB)

http://www.instructables.com/id/A-watering-controller-that-can-be-home-networked/

[NOTE: When saving, if you see .tmp as the file ext, rename it to 'Sprinkler-Controller-Schematic-v1.pdf']

Step 2: Making the board

To make the PCB, I used press-n-peel and toner transfer, as I do for all of my projects.

Essentially, I print the PCB layout onto some toner transfer paper.  I use Press-n-peel Blue, which costs a bit of money, but is beautifully reliable.  That is then laminatedonto some clean PCB stock the paper is removed, and the layout is touched up using a permanent marker where there are dust spots.

Then I etch the board using a mixture of 120mL Hydrochloric Acid, and 240mL of Hydrogen Peroxide (20%) - The excess copper is dissolved in about 5 minutes, then theboard is thoroughly washed to ensure that all acid is removed.

Then I scrub the toner material off the board using steel wool, and protect the board using a solder through spray lacquer.

Finally, I drill the board using my trusty Dremmel (Which has been working great for 20 years)

I have made hundreds of boards using this method, and it works really well.  Just be very careful using acids - wear eye protection, old clothes, and gloves.  And makesure that you protect your stainless steel laundry sink.  I protect mine by filling it with 10Litres of water, that way when a couple of drops of acid end up in it while I amrinsing off a board, it is diluted by lots and doesn't damage anything.    :-)

Step 3: Soldering the components

Once the board has been made, I solder the parts onto it.

My board needed a few jumpers, because I can't make double sided boards at home, so I soldered them in first.

I used surface mount parts for some of the components.  These were soldered onto the back of the board next.  These components are simple to solder and it is wellworth taking the effort to get them soldered - as I do more and more of them, I am finding it easier and easier.

There are many great instructables on how to solder surface mount parts, just have a look at one of them for ideas.

After the surface mount parts are soldered, continue by soldering the rest of the components. 

I have created an assembly manual that shows the steps that I used.  If I decide to make kits, this will be the manual that I will supply.  It is attached.

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Image Notes1. The 74HC08 in place!

Image Notes1. Power Connector2. Solenoid Common3. Pump output4. Output 5,4,3,2 & 15. Battery Backup for the clock - 4.5VDC6. Debugging and programming connector7. Reset Switch

File Downloads

Sprinkler-Controller-v1-Manual.pdf ((595x842) 800 KB)[NOTE: When saving, if you see .tmp as the file ext, rename it to 'Sprinkler-Controller-v1-Manual.pdf']

http://www.instructables.com/id/A-watering-controller-that-can-be-home-networked/

Step 4: Programming the micro

After all of the parts have been mounted, load the code into the micro.

I use a FTDI USB-TTL cable for all of my Arduino programming work.  If you don't have a cable, you can use your Arduinoboard.  Simply unplug the micro from yourboard, plug in the ATMega328.  Program it as per normal, and then move the programmed chip into the sprinkler controller.

Easy!

Here is the code for the project as a PDE file.

File Downloads

Sprinkler_controller_ACT_Government_Rules.pde (32 KB)[NOTE: When saving, if you see .tmp as the file ext, rename it to 'Sprinkler_controller_ACT_Government_Rules.pde']

Step 5: Testing and programming

Now that you have the micro programmed, plug it into the board, and apply power.

The yellow led at the bottom of the board should flash a couple of times.  If it does - YAY IT WORKS - if it doesn't, check for solder shorts and misplaced components.

Connect an ethernet cable between the board and your computer.

Make sure that the IP of your computer is 192.168.1.1 (for the default range in the code), open a web browser to 192.168.1.2, and you should see the screen below!

If you can see it - you are there.  Set the clock, and define when you want the watering to happen, and create your program.

There you have it - you are there!!!!

If you decide that your home network is on address 10.0.0.x then you can simply modify the line in the PDE file to put the controller on the 10.0.0.x network and re-program the chip.

ie change these lines from this:

static uint8_t myip[4] = {192,168,1,2};      static char baseurl[]="http://192.168.1.2/";

to

static uint8_t myip[4] = {10,0,0,12};static char baseurl[]="http://10.0.0.12/";

http://www.instructables.com/id/A-watering-controller-that-can-be-home-networked/

Step 6: Parts ListCapacitors

10uF SM  x 418pF SM x  40.1uF SM x 3

Resistors51R   x 4270R x 12470R x 62K7 x 110K x 3

SemiconductorsAtMega168 micro (DIP)   x 1DS1302 RTC (DIP)  x 1ENC28J60 Ethernet (DIP) x 174HC08 AND Gate (SOIC) x 1GREEN LED 5mm x 6YELLOW LED 5mm x 1RED LED 5mm x 1BLUE LED 3mm x 2BC547 Transistor x 61N4004 Diode x 716Mhz crystal x 132768Khz Crystal x125 Mhz crystal x 178L05 Regulator x 178L33 regulator x 1

Hardware2 Pin PCB screw connector x 43 Pin PCB screw connector  x 16 pin 0.1 inch pin array x 1Small Pushbutton x 2RJ45 MagJack from Sparkfun x 1(http://www.sparkfun.com/commerce/product_info.php?products_id=8534)8 Pin IC Socket  x 128 Pin IC Socket x  2

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Step 7: PCB Artwork

Here are the PCB files for toner transfer

File Downloads

Sprinkler-Controller-v1-Component.pdf ((595x842) 41 KB)[NOTE: When saving, if you see .tmp as the file ext, rename it to 'Sprinkler-Controller-v1-Component.pdf']

Sprinkler-Controller-v1-Copper.pdf ((595x842) 86 KB)[NOTE: When saving, if you see .tmp as the file ext, rename it to 'Sprinkler-Controller-v1-Copper.pdf']

Sprinkler-Controller-v1-Jumpers.pdf ((595x842) 27 KB)[NOTE: When saving, if you see .tmp as the file ext, rename it to 'Sprinkler-Controller-v1-Jumpers.pdf']

Step 8: Where to now?

I am glad you asked...

1.  I will be extending the code to be more general - Not everywhere on the world has the ODDS and EVENS system in place, and some people can water whenever theywant.  The code changes should be pretty minor.

2.  In an ideal world I would understand how to make the interfaces better.  At the moment, string space on the ATMega328 is sooo limited that it has been a shoehorning exercise getting everything to fit.

3.  Adding recording data would be great - It would be cool to ask the watering controller how much water I used this month.

In all - lots of options to improve the project - but this is the point where I had to say - "That will do Pig, That will do'.

If you don't understand the reference above, you need to hire a copy of 'Babe from 1995' 

PS - There is no security on this device - making it accessible to the whole world via the Big Bad Internet (tm) would be a bad thing.  Would you give the Internet accessto your tap out the back of your house???  I didn't think so :-)

Step 9: DC vs AC Solenoids.

There have been many comments on this Instructable regarding DC vs AC solenoids.

I am using Rainwater 24V AC Solenoids - and they operate well using 12V DC.

Essentially, when operating a solenoid outside it's design specification, you have to understand that your experience may vary, depending on the manufacturer.

As one posted indicated, the inductance of the coil is what limits the current flowing through the solenoid to a safe value when driven in an AC circuit.  In a DC circuit,there is no inductance, just the resistance of the coil.  I would never recommend operating a 24V AC coil at 24V DC, that will certainly overheat the wiring, leading topremature failure.

One commenter did mention that using a coil with DC will increase the amount of heat that it had to dissipate - This is correct, as long as you don't reduce the supplyvoltage.  Depending on the DC resistance of the coil, you may find that your specific coils run just fine.

My advice, use a 12V battery, and a multimeter measuring current, and see whether (a) the coil is pulled in enough to run, and (b) how much current is flowing when thecoil is energized.  As long as there is less than about half an amp, then you are likely to have no problems.

I am working on a 24V AC version of this design, so that peoples concerns are alleviated - but that won't run using a solar cell as it needs an AC supply to operate.

Related Instructables

AutomatedSprinklerSystem AnyoneCan Do! byshepnstein

A RemotelyProgramableRelay Controller(ChristmasLights or HomeAutomationController) bydrj113

How to make aLinux poweredgarden sprinklersystem. bybkimmons

Cheaptouchpad. byComputothought

Rainwater dripirrigationsystem by TreeFrog

Help! Where aremy SprinklerValvesLocated? bythb43

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Comments

48 comments Add Comment

 terys2 says:  Mar 8, 2011. 3:21 PM  REPLYHi with what program i compile the .pde file .Thnx in advance

 drj113 says:  Mar 10, 2011. 4:09 AM  REPLYThe .pde file is an Arduino sketch. It is designed to be loaded with the Arduino IDE.

 falk3n says:  Mar 2, 2011. 5:58 AM  REPLYI hope you are good friends very well I think it's great your project but you could be q up the libraries that the program gives me error e downloaded theselibraries appear and persist errors by

 drj113 says:  Mar 2, 2011. 12:28 PM  REPLYNo problems - Which libraries do you need?

 CODIY says:  Nov 15, 2010. 6:43 PM  REPLYWonderful Instructable Doug! I am in the planning stages for a similar controller for my garden irrigation, though I plan to use zigbee to interface with thecomputer.

I was wondering on the odd/even day of the week determination whether you had considered using the modulo function. By dividing by 2, the modulo wouldalways be either 1 or zero, so to determine whether to water or not, you would just have to determine if the modulo of the date results in a 1 or zero.

 Wire54321 says:  Nov 14, 2010. 8:22 PM  REPLYhaving alot of problems with the come "Time time;"

and do i need to download anything if so where?

 Wire54321 says:  Nov 14, 2010. 6:31 PM  REPLYPlease Can you make one with 6-Zones. And possible with a port for bluetooth or can i use programming port?

A++ for pump mode

 agis68 says:  Oct 23, 2010. 5:08 PM  REPLYExcellent Job, well made and projected....5/5

 inventgeek says:  Oct 13, 2010. 7:39 PM  REPLYI have a strange problem with my setup. The web examples don’t work but the link lights come on. and the leds flash appropriately for the loading of the encchip and if i load the ping sketch it will respond but destination as unavailable. the leds blink with traffic but it seems like part of this are not working right.anyone run into this type of issue?

 drj113 says:  Oct 14, 2010. 12:32 PM  REPLYHi,

The standard reason that people have problems wit hthis project is that they don't use a magjack - or that they have a transposition error between the TXand RX lines on the Ethernet side, or that the computer is on a diferent network number range to the project.

If the LEDs flash on boot, then the communications between the micro and the Ethernet controller are correct. just check the use of a Magjack, and makesure you are either (1) plugged into a hub, or (2) using a crossover ethernet cable from your computer.

Also, double check your network settings - it is important that you are on the same network as the project, as it has no routing capability. Also doublecheck the address you set up in the code.

Take care,

Doug

 kyle brinkerhoff says:  Oct 6, 2010. 9:17 AM  REPLYhow much if i asked you to make me one ?

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 gentry says:  Sep 27, 2010. 8:08 PM  REPLYAwesome. This is exactly the project I wanted to do for our home irrigation system, since the commercial watering controllers have horrible UIs.

You mention that you protect your boards with a solder-through spray lacquer -- do you have a brand name or a supplier?

 drj113 says:  Sep 27, 2010. 9:33 PM  REPLYIt is an Australian Brand called Servisol.

It can be purchased from Jaycar.

http://www.jaycar.com.au/productView.asp?ID=NA1002&keywords=lacquer&form=KEYWORD

 djairjr says:  Sep 15, 2010. 9:37 AM  REPLYAmazing instructables!It is possible do the same with wireless conection?

 drj113 says:  Sep 15, 2010. 2:26 PM  REPLY

That is an awesome idea - I am sure that it could be done, using some of those inexpensive rf data link modules.  I am not aware of a way that I couldget 802.11 actual wireless networking into the design.

With an rf data link module, I suspect that the architecture would change completely - we wouldn't have to implement a web server in the box, becausewe could simply implement a simple remote control protocol.

I don't think I would go to the extent of having wireless solenoid controllers.  The current drain when they are operating would destroy batteries veryquickly :-)

 sdgenxr says:  Sep 20, 2010. 1:21 PM  REPLYWireless option would be awesome! Then you could easily feed data to a computer that runs 24/7 and create graphs and such from there.

(Patiently waiting for the WiFi version)

 acksheep13 says:  Sep 16, 2010. 3:52 AM  REPLYActually if you have an open plug near where you are you could use a Wireless Network Bridge WNB. This lets you plug it into the computer for yourinfo then you plug it ino the ethernet port on your system after programmed and it should latch onto any wireless network it is programmed to.

 jrawling says:  Sep 19, 2010. 6:37 AM  REPLYRegular solenoids (in North America) prefer 24 Volts AC. Since I have 12 Volt DC draught (remote property, solar) I would like to use that to run my irrigationsolenoids. Can I feed 12VDC to a 24VAC solenoid and make it function?

 cyberdove says:  Sep 19, 2010. 6:40 PM  REPLYNo, it won't work with 12v.

 drj113 says:  Sep 19, 2010. 7:24 PM  REPLYDepending on the manufacturer of the solenoid, you may find that it works - Mine are made by Rainbird, and they work fine on 12V DC - you have totry it yourself though.

Doug

 drj113 says:  Sep 19, 2010. 2:18 PM  REPLYI discovered that my solenoids were happy with 12VDC just by trying it out - If they turn on and off with 12VDC, then they are ok.

 leadpencil says:  Sep 19, 2010. 8:58 AM  REPLYYou can get a 9volt dc magnetic latching solenoid for the big three (toro, rain bird, hunter)

 databoy says:  Sep 19, 2010. 8:46 AM  REPLYSimple answer is NO. AC and DC are different power systems. DC will burn out AC coils.

 Gooru says:  Sep 19, 2010. 5:56 PM  REPLYIf only the answer were that simple. Yes, AC and DC are different power systems (Alternating Current vs. Direct Current). It's a case of Tesla versusEdison.

In a DC circuit, the "resistance" will limit the flow of current. The same is true in an AC circuit, but there is an additional component called"impedance". This one is a lot tougher to measure because it hinges on the ability of a coil to resist the formation or collapse of a magnetic field. Asolenoid or relay coil of a given resistance must operate at a higher AC voltage in order to overcome both components. There is also a differencebetween "peak" and "RMS" voltage, but that's going a bit too deep for this discussion.

The bottom line is that most AC solenoids or relays will function just fine on DC, but at a reduced voltage. The trick is to keep the current through the

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windings within spec.

 databoy says:  Sep 19, 2010. 8:53 AM  REPLYI will add to the above comment. I am a qualified electrician, I live in Australia. The local 24 volt coils will not work on DC; if they do work, the localheat 40 degrees C in the summer will overheat the coils.

 drj113 says:  Sep 19, 2010. 2:22 PM  REPLYThats interesting - Thanks for your thoughts.

I never water during the heat of the day - it is really bad for the plants - and the local council only allows watering between 7pm and 10pm in anycase.

Do you know what is different between an AC and a DC coil?  What manufacturing difference is there?

 Gooru says:  Sep 19, 2010. 7:37 PM  REPLYThe difference between an AC and a DC coil can be substantial or none at all. Years ago I toured a Siemens plant where one line wasmanufacturing relays for a third party vendor (name never mentioned). We watched the automation wind and solder coils, assemble thecontacts and armature, then snap on colored caps. The caps were preprinted with the pin outs and specs; yellow caps for DC, green for AC. Itwas the same component under the cap. The engineer leading the tour explained the design parameters allowed the relay to function under awide range of voltage, AC or DC.

On the other hand, a design can be very specific. This is especially true where size, efficiency, response time or environment is paramount. Inthis case a variation of voltage of as little as 10% can fail a component, or at least shorten its life significantly.

Someone mentioned that DC could magnetize an AC relay or solenoid, causing it to stick. Some DC “latching” relays are designed to do justthat. The AC version requires a mechanical latch. Magnetic stiction might be a problem for coils with a ferrite core, but ferrite costs more andrequires special handling. Most relays and solenoids use laminated steel which resists both residual magnetism and hysteresis currents. Thelatter contribute to heating when the coil is left energized.

So while running an AC coil on DC might not work, it often does usually at a somewhat lower voltage. You could spend a lot of timeresearching whether one specific device will function or not, and someone will always tell you it won’t. The only way to tell for sure is to plugit in and try it. Measure the current, monitor the temperature, and if it doesn’t catch fire you are good to go.

 drj113 says:  Sep 19, 2010. 8:16 PM  REPLYYep! --- There is nothing wrong with giving it a go!

 BlueFusion says:  Sep 19, 2010. 7:51 AM  REPLYShort answer - yes.Long answer - yes, but they don't like it much. They will work, but you may end up magnetising them from the DC - which means they could get stuck onor off.Basically, it works, but you reduce the lifetime of the solenoid.

 manicmonday says:  Sep 19, 2010. 9:22 AM  REPLYAnyone have any ideas about building a diy electrically activated on/off water valve? Once you have that you can create as many as you want, and controlthem in any number of ways.

Come to think of it I haven't contacted the plumbing supply to see if they sell anything like that at low price. I have checked at Walmart and they sell them for$30 each as part of a programmable water timer system. I will call the plumbing supply tomorrow and keep you all updated.

 drj113 says:  Sep 19, 2010. 2:29 PM  REPLYI appreciate the idea of a home made watering valve, but the possibility of a failure occurring in it makes me just be happy to pay the $30.

Water is just to precious to loose through a construction failure.

Our local Bunnings sells buckets of commercial valves at about $30 each.

 rvbcrs says:  Sep 19, 2010. 9:10 AM  REPLYWow drj113 what a good project really nice!! I just hope on thing, do you think you will ever make this same project but then just out of smd components? Iwould really love that!

 jamwaffles says:  Sep 19, 2010. 6:12 AM  REPLYNice PCB!

Can I ask what software you use? Eagle is so very nice but the board size is so very limiting! :(

 evildeece says:  Sep 17, 2010. 6:38 PM  REPLYYou're in the ACT? Awesome! We're building a hackerspace and have maker meetings every alternate Tuesday. You're welcome to join - Make Hack Void

http://www.instructables.com/id/A-watering-controller-that-can-be-home-networked/

 drj113 says:  Sep 18, 2010. 4:10 AM  REPLYWow - That would be awesome - I will have a look at when I can drop over - Thank you!

 diamantmatch says:  Sep 17, 2010. 4:09 PM  REPLYhello

i dont understand how you keep power on the RTC chip when it loses power.in the skematic it says that there is a cap between it's backup pin and gnd but it is called capapol and i dont know wich one that is?somewhere in the parts pdf i found that it only charges it's battery when it is told to ?

thank youdiamantmatch

 drj113 says:  Sep 18, 2010. 3:34 AM  REPLY

I use a set of 3 AAA cells, providing 4.5v to the right controller connection - that is where the supply to the RTC chip directly.

 diamantmatch says:  Sep 18, 2010. 2:44 AM  REPLYhello again :)

can you upload the librarys to?i dont have the lib for ds1302 and etherlib and stuffthank youdiamantmatch

 diamantmatch says:  Sep 17, 2010. 6:53 AM  REPLYwow your'e featured on hackaday! congratulations!thank you for the pcb files it is really usefull!

 kyle brinkerhoff says:  Sep 15, 2010. 10:03 AM  REPLYthat looks almost identical to your relay board:] but still great work!

 drj113 says:  Sep 15, 2010. 2:22 PM  REPLYHi,

You are pretty well right - My focus was kind of having built an enabling technology (The Arduino Ethernet Board), there were many things I could do. And my wonderful wife did suggest that instead of working on the awesome arduino music project I have working in the back of my brain, I could finishthe job I started a couple of years ago when I said I would replace the sprinkler controller :-P

 kyle brinkerhoff says:  Sep 16, 2010. 10:55 AM  REPLYnow if you made it have the ability to change the polarity on the outputs, it would be perfect for robotics

 diamantmatch says:  Sep 15, 2010. 11:02 PM  REPLYhello

can you upload the schematic files from eagle cad please?it would certeanly help because i wouldnt have to do everything by hand :)

thank youdiamantmatch

 drj113 says:  Sep 15, 2010. 11:17 PM  REPLYHi, I am very sorry, but I don't use Eagle because it is not open.

Eagle is severely restricted in the size of PCB that it can make in the freely accessible version in that it can't be used for projects greater than 4" x 3.2".

Given that my Workclock project was 6" x 6" I couldn't use Eagle.  So I searched for an open source alternative.

I use KiCad, which has no restrictions, and is fully open.

I am very happy to provide Kicad schematic and PCB files if you like.

 diamantmatch says:  Sep 16, 2010. 4:11 AM  REPLYHey, oh sorry i thought you where using eagle.But if you can provide me with pcb files , that will be great.

thank youdiamantmatch

http://www.instructables.com/id/A-watering-controller-that-can-be-home-networked/

 drj113 says:  Sep 16, 2010. 5:25 AM  REPLYNot a problem at all - Send me your email to doug@doughq.com - and I will respond tomorrow morning.

Doug

 diamantmatch says:  Sep 15, 2010. 12:36 PM  REPLYhelloi can not seem to find the ENC38J60 but i have found the ENC28J60 on ebay but it is rather expensive.. (well expensive.. XD 5 dollar but still) is it okay touse a ENC28J60 in my circuit instead of the ENC38J60?what is the difference in them?

thank you very much i really adore your projects i truly think they are wonderfully build and designed

thank youdiamantmatch

 drj113 says:  Sep 15, 2010. 1:43 PM  REPLYWhoops - it was suposed to say ENC28J60 anyway --- I have fixed the instructable.

Doug