[Michiel] likes to wash his clothes in warm water. Like a lot of machines, his draws from the cold water line and heats it electrically. Gas is much cheaper than electricity in the Netherlands, so he wanted to be able to heat the water with gas instead. Hot-fill machines already exist, but few models are available and they’re all too expensive. [Michiel] rolled up his sleeves and hacked his brand new washer into a hot-fill machine.
He started out thinking that he’d just connect the hot water line instead, but that proved to be too hot. He found out it needs to be about 35°C (95°F), so he decided to mix input from the hot and cold lines. Since it’s a shiny new machine, [Michiel] wanted an externally mounted system to keep from voiding the warranty. He got two solenoid valves from the electronic bay and used a PIC16F to make them dance. He wired up a light switch on a two-panel face and used the blank plate for power and status LEDs.
[Michiel]’s design works like a charm. The machine used to draw 2000W to heat the water, and peak usage now is as low as 200W. He noticed that the washer drew a lot of power in standby mode so he added a solid state relay and a bit more code. Now the electricity to the machine is cut after two hours and [Michiel] saves about €97 per year.
[Ben Jones] just started a new site called Maker-Guide, where he makes some very informative and well produced DIY videos on anything from homemade photography hacks, to controlling an outlet using a solid-state relay.
It’s not the first time we’ve seen a relay controlled outlet, or this one… but it’s certainly one of the cleanest jobs we’ve seen. In his video guide, [Ben] shows us exactly how to fit a standard solid state relay into a regular outlet box, and easily control it with an Arduino Uno.
It even looks like there might be enough space inside the box for a small wireless setup — maybe using a Trinket even? What about using Power-Line networking to control each box via LAN? Could be the easiest home automation implementation yet! Well, aside from certain NEC (national electrical code) concerns of running high and low voltage in the same box…
Anyway if that wet your whistle, check out the great video guides after the break!
Continue reading “DIY Home Control Using a SSRelay”
[Tim] is a homebrewer. Temperature profiling during the mashing process is apparently even more critical than the temperature curve of a solder reflow oven. His stove just wasn’t giving him the level of control he needed, so [Tim] added a PID temperature controller to his stove. Electric stoves generally use an “infinite switch” to control their burners. Infinite switches are little more than a resistor and a bimetallic strip in a single package. Not very good for accurate temperature control. The tricky part of this hack was to make it reversible and to have little visual impact on the stove. A stove top with wires hanging out would not only be dangerous electrically, it would also create a hazardous situation between [Tim] and his wife.
[Tim’s] brewpot only fit on the stove’s largest burner, so that was the only one that needed PID control. To keep things simple, he kept the commercial PID controller outside the stove’s enclosure. Inside the stove, [Tim] added a solid state relay. The relay is mounted to a metal plate, which screws to the back of the stove. The relay control lines run to an audio jack on the left side of the stove. Everything can be bypassed with a switch hidden on the right side of the stove. In normal operation, the switch is in “bypass” mode, and the stove works as it always has. When mashing time comes along, [Tim] flips the switch and plugs the jack into his PID controller. The temperature sensor goes into the brewpot itself, so no stove modification was needed there.
The end result is a very clean install that both [Tim] and his wife can enjoy. Save a few bottles for us, [Tim]!
[The Cheap Vegetable Gardener] assembled his first grow controller about three and a half years ago. He’s been very happy with it and knows that he’ll be using it for years, maybe even decades to come. He just finished overhauling the grow controller design to help make sure he doesn’t burn down his garage one day. You have to admit, without knowing anything about the project this rendition does look safer than his original offering.
Pictured above is the weather-proof enclosure he used to house four mains-rated solid state relays. This box is isolated from the control hardware, providing heavy-duty utility plugs to interface with the heater, lights, fan, and water pump. He mounted the Arduino board which controls the relays to the outside of the box, using the Ethernet wire to switch the SSRs. It uses a manufactured shield he designed which will help ease the pain of fixing the system if parts ever go bad.
Later on in the build he shows the grow light and heaters used in his operation. The heaters simply screw into light sockets; something we’ve never come across before.
This breadboarded circuit is [Sergio’s] solution to controlling appliances wirelessly. Specifically he wanted a way to turn his pool pump on and off from inside the house. Since he had most of the parts on hand he decided to build a solution himself. What he ended up with is an RF base station that can learn to take commands from different remote devices.
The main components include the solid state relay at the bottom of the image. This lets the ATtiny13 switch mains voltage appliances. The microcontroller (on the copper clad square at the center of the breadboard) interfaces with the green radio frequency board to its left. On the right is a single leaf switch. This acts as the input. A quick click will toggle the relay, but a three-second press puts the device in learning mode. [Sergio] can then press a button on an RF remote and the device will store the received code in EEPROM. As you can see in the clip after the break, he even included a way to forget a remote code.
Continue reading “RF switching module can learn new remotes”
We like our nice, safe, 5V prototyping projects where the only thing that might get fried is a chip. But there are times when you want to switch appliances for one reason or another and then you’re going to want a mains rated relay. [Viktor] got tired of having exposed high voltage on the bench during the prototyping stage of these projects so he recently built a solid state relay test box.
The only thing he bought for the project was the SSR itself. To act as an enclosure he used the brick from an old laptop power supply. This is perfect for a couple of reasons. First off, it’s designed to contain high voltage if there is ever a short or other problem. Second, it’s already setup for incoming and outgoing power. He just needed to remove the guts and mount the relay. Notice that it comes with a clear plastic shield that physically separates the high voltage side from the low voltage control end. This, along with the cable routing, keeps the dangerous stuff on one side to ensure you won’t get an arc to the low voltage portion of the project.
[Dave] built a controller that lets him boil two kettles at once when brewing beer. The setup uses electric heating elements in each of the kettles. We prefer to use gas as it’s a bit easier to control temperature. But an electric system like this can be used inside during the winter months while propane is relegated to the outdoors. The other thing that immediately comes to mind is partial mash recipes that require steeping in one kettle, then sparging (rinsing off the grains) with water of a different temperature. That kind of thing is a snap since the two are controlled individually by the trimpots on the front of the control box.
Inside you’ll find two 220V solid state relays. The box itself plugs into the 220V outlet in his basement which is normally occupied by his clothes dryer cord. So as not to blow a fuse, the MSP430 chip driving the relays switches back and forth between them rather than turning both on at once. The system uses entirely manual control, but it should be an easy modification to add a thermocouple and PID algorithms if so desired.
After the break [Dave] shows off the system in a video clip.
Continue reading “Double-kettle boiling rig for and easier brew day”