AFCI circuit breakers and the problem of ‘nuisance tripping’ | 19mm Momentary Push Button

Although a mains powered heated bed sounds scary for a hobbyist-built 3D printer, there are a number of positives to the design. It would heat up faster, thin down a few parts, and significantly reduce the overall cost of the printer by not requiring another 100 Watts delivered from a 12V power supply. It’s a great idea if it doesn’t burn down the house. Anyone want to help?

Toasters kindof have to use mains voltage, there’s a kilowatt or so of power in there. They do their best to keep the mains voltage away from hands, you’d have to deliberately put your fingers in to get shocked. Always remember to switch off at the wall before you stick the knife in to dig out your crumpets!

ead of single layer traces covered by the paint, what about multilayer PCB? So the traces would be embedded between two FR4. This way it would be safer.

You probably knew that, so I apologize if I’m going over familiar ground, but for others, it’s worth mentioning.

While the translucent mirror design isn’t quite as space-efficient as the mirrorless design of an SLD camera, it’s still smaller than that of a traditional SLR, most of which need to provide room for the mirror to swing upward before image capture can commence. That translates to an uncommonly compact body by SLR standards, although it’s still a bit larger than an SLD, especially in terms of body thickness. Unlike SLD cameras, though, the Sony SLT cameras all accept the entire line of standard Alpha-mount lenses, a significant advantage if you already own a large collection of Alpha-mount glass.

The only people having trouble with L1 are those DOPES who haven’t read their owner’s manuals. There all EV manuals state that car charging is a heavy continuous load, and it requires high-quality receptacles that have been tested to make sure they are safe by someone competent.

When I was a about 12, my mother decided to fault find a 35mm slide viewer. 240vac in, 6vac out of the transformer to a plug which fitted a socket under the viewer. Slide closed two metal contacts.

But at the very same time, if the rectifier dissipates enough energy for this to be a concern, then it is probably a poorly designed power supply to start with. As most power supplies will be designed for the voltage range of 110 to 250 volts AC. And as it will draw the most current down at 110 volts, then this is where the manufacturer has their specifications chiseled in stone, as if we want 1100 watts, then we need at least 10 amps when we have 110 volts AC on the input. This means that we “effectively” have 5 amps to dissipate per diode.

As an engineer over 20 years ago I coined the term Beancounter Engineering this kind of stuff where some Idiot MBA sets the specs based on saving a few pennies rather than a Electrical Engineer that understands basic (and complex) science. If you are too damned stupid to understand the basic science behind Global Warming you have no business being an engineer or telling engineers what to do

It calls out a MOC3041M on the silkscreening. One can use a MOC3041 of course as they are the same form factor.

But I don’t like the mains powered heater in this case: If you take 120W @24V its just 5A. No problem for a switching transistor or wires with 0,5mm² and you keep the mains voltage in the PSU box. Which I prefer in this case. Mains rated cabling (230V here in Europe) are not thinner and need thicker insulation. In the worst case you have to have PE connection to any metal part of the construction.

Then when you step up a notch to the KV stage the safety rules change because air can now be a conductor.