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Sprinkler Timer¶
I needed a device to time my sprinklers, because I had been forgetting to turn them off. So I made a very simple program to turn them off after some number of minutes.
Hardware¶
- Tested on the LPC1768
- Either board should work
- You will also need some way of controlling the flow of water (like a solenoid valve and a relay). My test equipment:
- 12V Rainbird valve (Rain Bird 3/4-Inch Sprinkler System Automatic In-Line Valve)
- relay (SainSmart 2 channel relay)
- 12V power supply (Replacement LCD Monitor Ac Adapter 12v 5a)
- Some Button for start/stop
- Some way of powering the board (maybe someone can help me power it from the 12v supply)
Connections¶
Button:
- One side to pin 5
- the other to Vout
Relay:
- Vcc to Vout
- Gnd to ground
- IN1 to pin 6
Directions/Use¶
Do not hold button while restarting!
I have experienced negative effects during testing while the button was held on. If you have problems and suspect this you may need to reflash your chip
- The button will start the sprinkler when it is off and vice versa.
- Once started if not interrupted, the sprinkler shall run for 25 minutes.
Future¶
Future versions will have an array of outputs, so you can run sections with one button push.