(Previously I discussed the the why of this project, the parts I selected to build with, setting up the Raspberry Pi itself, the electronic assembly, the mechanical assembly in the backyard, and the Rasptimer software I wrote for it.)
Here’s the project bill of materials, not counting things like that I replaced or improved “while I was it”, but just the ones core to the project:
| Item and source | Approx. cost | Total | |
|---|---|---|---|
| 1 | Raspberry Pi Model B (from Newark) | $35.00 | $35.00 |
| 1 | Wi-Pi USB adaptor (from Newark) | $16.48 | $16.48 |
| 1 | 4 GB SD Card (from Fry’s) | $7.00 | $7.00 |
| 2 | Deltrol Relay 267F DPDT (from onlinecomponents.com) | $14.16 | $28.32 |
| 1 | Power supply 5V and 12V (from Sparkfun) | $9.95 | $9.95 |
| 2 | MOSFET 30N06 (from Sparkfun) | $0.95 | $1.90 |
| 2 | 10K resistors (bought bag of 10 from Sparkfun) | $0.95 | $0.95 |
| 2 | 1N4001 diode (from Sparkfun) | $0.15 | $0.30 |
| 1 | Prototyping board (from Sparkfun) | $2.95 | $2.95 |
| 1 | Aluminum enclosure (similar to this from Fry’s) | $20.69 | $20.69 |
| 1 | Plastic enclosure to keep Wi-Pi out of the metal box and protected from weather (similar to this from Fry’s) | $7.99 | $7.99 |
| 1 | Terminal wire connectors (from Lowe’s) | $2.06 | $2.06 |
| 1 | micro-USB chord (from Fry’s) | $1.99 | $1.99 |
| 1 | USB extension chord (from Fry’s) | $3.29 | $3.29 |
| 1 | Custom front panel for control box (from Advantage Metal Products) | $20.00 | $20.00 |
| Various little odds and ends, like a few feet of 16-gage stranded wire, soldering material, screws, bolts, nuts | $5.00 | ||
| Total: | $163.87 | ||
Not a bad price. I note that Leslie’s sells mechanical timers for pump control at $77.99 each. If I had used those, I also would have had to pay for the custom faceplate, and the total would have been $175.98, which is slightly more. But with none of the goals that I set out for the project, like remote control, or adaptive scheduling.
Now all that’s left to do is to create a video showing the system in action…