[Debraj Deb] put together a current monitoring device that interfaces with the circuit box at his house. The system is controlled by a PIC 18F4520 and uses an LM358 Op-Amp to rectify the AC signal, as well as an MCP6S21 for range adjustments for detecting both high or low current loads. The data displayed on a character LCD includes average, RMS, and peak current. For now the data is saved to an EEPROM and can be dumped using a serial connection but [Debraj] plans to add a GSM modem so he can send energy use data to his cell phone.
Reader [Tim Upthegrove] sent in a novel take on powering and monitoring AC outlets and devices called SPRIME, or Simple Powerline Remote Interactive Monitor and Enforcer. Compared to previous hacks, such as 120v switching or Quick cheap remote outlets, that only turned an outlet on or off; SPRIME allows not only control over outlets via the internet, but also power usage of devices currently plugged in.
We really liked their idea of giving power companies access to SPRIME outlets to reduce power consumption during peak hours, but sadly we don’t see it being implemented in homes any time soon. Catch a video of SPRIME after the rift.
[Thanks Chris McClanahan and Jeff Starker for the project, and deyjavont for pointing out our silly mistakes]
Continue reading “SPRIME controlled AC outlets”
Update: This How-To was written for April Fools’ Day. It is not advised you attempt to make or even use this cable. The comments have made it very clear how dangerous to you and others using this cable can be. The image above is not of a full male-to-male cable, only the ground is connected, and the generator is not running.
We all know Ethernet has the crossover cable, cars have jumper cables, and RS232 has the null modem. Well, it is about time our wall sockets get their own crossover cable. This crossover cable is great for running power to a circuit disconnected from power. Maybe you are out of fuses, the breaker is broken or you just don’t want to go check the fuse box when there is a murderer about. This cable makes a great gift for even the most loathsome of acquaintances. Continue reading “How-to: Make a Mains Crossover Cable”
[Freeload] sent us his custom MagSafe adapter build for laptops. MagSafe for those unaware is Apples (patented) power adapters that prevent damage to laptops when the cord is accidentally yanked from the socket. While we’ve seen some custom versions before of MagSafes they were usually bulky, ugly, and used a ton of unremovable glue. We really like [Freeload’s] because its quick, good looking, and the best part – completely removable without marks or damage. In short, an easy weekend project that could one day save your laptop.
[Kenneth] built a 5v controlled power outlet inside of a junction box. We’ve seen plenty of projects that can switch 120v outlets using 5v logic for refrigerator controllers, lighting controllers, or grow systems, but they almost always use solid state relays to facilitate the switching. This iteration uses mechanical relays along with the necessary protection circuitry. The project is housed in an extra deep single-gang box and allows for individual switching of the two outlets. You can see this connected to an Arduino switching two lamps after the break.
Continue reading “120v switching”
[Rosenberger31] did a nice job of adding a USB port to his 2010 Toyota Prius. He removed the access door on the console where the traditional “cigarette lighter” 12 volt port is located. A Dynex 12-volt to USB adapter was piggy-backed onto the power lines and the USB connector was then fit into the blank accessory plate next to it.
There is no data connection here, the port only provides 5v regulated power to devices plugged into it. None the less, it is still a pretty nice looking alternative to having a power adapter hanging out of the dash all the times. If you try this, heed one of the warnings from the comments and make sure you add a switch if you vehicle powers the 12 volt port even when the car is not running.
This makes us wonder: will this void your warranty?
[Colin] has put together an instructable for a solar power generator that uses the thermoelectric effect instead of the photovoltaic (PV) effect. We have seen Peltier devices used in cooling cans, solder paste, backs, and hacked hard drives. This is the first hack we have seen where a Peltier device is used to generate electricity from heat, essentially running the device backwards. The thermoelectric effect is the same principle that is used to generate electricity in radioisotope thermoelectric generators used in deep space probes such as Cassini. What applications can you come up with to use the thermoelectric effect as a power source?