Turn a wall outlet into a wireless charger with the Legrand Radiant | Lrd12 Overload Relay

Chances are almost anything you would want to power on and off through a Smart Plug will work. Lights — whether incandescent, LED, or fluorescent — are compatible as long as they are standard devices intended for use in the home (something like a street lamp or traffic light probably won’t work) and should work flawlessly. Audio-visual equipment should work provided it doesn’t need a power cycle through the built-in switch, and other smart devices like cameras or home hubs should work just fine.

A couple months back I ran across a note in the datasheet for an inexpensive but reputably sourced power MOSFET that said that, while the die itself was rated for 200A continuous/400A peak the package and its leads were only rated for 125A/250A. So I said to myself “I wonder what the mode of failure looks like?” And built up a circuit to drive it to failure in a controlled manner. It was fairly spectacular: 1) the thermal expansion rate of the die doesn’t match that of the package and once you exceed some wattage tension builds up and (at least in the case of my particular DUT) the chip package literally exploded sending shards of epoxy and/or ceramic flying far and wide. 2) with the die now exposed in several areas and the connection to the heatsink thoroughly hosed by the explosion of the package things devolved rapidly and the magic blue smoke escapes (which smells very bad, FYI, and takes a while to fully purge that smell from the workshop).

Combining breakthrough translucent-mirror technology with Sony’s high-speed CMOS sensor prowess, the new Sony Alpha A33 and A55 break important new ground for consumer SLRs. Both deliver higher capture speeds than other consumer-class digital SLR, at 7 and 10 frames per second respectively, as well as true phase-detect live autofocus during video recording. Thrown in multi-shot technology (Handheld Twilight, Sweep Panorama, and Auto HDR modes) brought over from Sony’s digicam line, and the new cameras offer features not found in any other SLR, regardless of price point.

I’ve left perhaps the most salient characteristic of the Sony AF55 and A33′s EVF till last: It’s huge. The view through the Sony A33′s eyepiece is much more akin to that of a full-frame DSLR than that of any competing sub-frame model currently on the market. It manages this with a comfortably high eye point (and plenty of dioptric adjustment) for eyeglass wearers, at least when simply viewing the live viewfinder image itself.

The reason may be the cost of getting UL approval. You can buy off-the-shelf, UL approved, 12/24VDC power supplies. Once you are working with 12/24VDC most products don’t need further UL approvals. But — if everything is mains power you are going to have to pay for a new round of UL testing. That can be $10,000 or more.

Hopefully one of these days we’ll go to significantly more DC distribution all over teh place, but I often wonder if I’ll see it in my lifetime. I thought I was imagining things when I was trying to remember if Japan was 50&60, but that’s pretty fascinating.

“Normal” mains voltage heating elements use nichrome (nickel chromium) some time called “resistance wire” because it has a higher resistance for a given surface area.

Called the MPSMv2, the core of the project is the ESP8266 module. The dev board itself can support anything with GPIO pins, whether it’s an Arudino, Raspberry Pi, or anything else with those features. Flashing the NodeMCU firmware is pretty much all that needs to be done in order to get the device up and running, and once you get the device connected to your WiFi you’ll be able to control whatever appliances you want.

• Circuit conditions such as the peak voltage and current during the surge event • The MOV continuous operating voltage (should be at 20% above maximum system voltage under normal conditions) • The number of surges the MOV must survive • Acceptable let-through voltage for the protected circuit • Any safety standards with which the circuit must comply

Chassis floats with just 2. My folks lived in the middle east before my dad retired and I visited them in 2013. You could feel 50hz on the refrigerator door handle. Touching their aluminum iMac gave a nastier jolt. I remember my dad telling me, “yeah, don’t touch that” after trying to plug in a USB stick.

The printer does not print onto the heater. The heater is normally under the bed which can be a variety of materials. I use polycarbonate, a lot of people use glass, I think most printers come with aluminium with Kapton tape on top. The heater for the bed is usually safely tucked away where you would need to be somewhat of a contortionist to actually touch it.

I think this could have failed purely due to the inadequate heat sink, made worse by elevated summer temperatures. Add the possibility of counterfeits in, it was doomed to failure.