This robot uses AI to find Waldo, thereby ruining Where’s Waldo | Lrd12 Overload Relay

All in all, the current draw through this device was below it’s “rated” value. So either it’s a fake/poorly produced or was simply defective.

I don’t know if the heat is high enough but mirror heating pads can be quite small and put under a sheet of glass would be quite effective.

Let us never forget this Darwinian hero. http://www.dailymotion.com/video/xfyyii_man-electrocuted-on-the-train-india_news

Of course a safe mains powered heater is possible, but you need a double insulated cable (which is stiffer and heavier) and a reliable strain relief for it. You have to permanently bond the heater PCB to the glass print bed with silicone. You need a fuse and a thermal cut out (thermal fuse) for fire safety, because the available power in the mains circuit is much higher.

I haven’t seen you around the traps here before and you have put in a good effort so welcome aboard.

Look and feel. Although it lacks the reflex mirror of an SLR, having replaced it with a fixed translucent mirror, the basic shape of the Sony SLT-A33 still follows that of a traditional SLR fairly closely. That’s because, since it accepts the same Alpha lenses as Sony’s DSLRs, the Sony A33 also has to accommodate the same backfocus distance, which is one of the main contributors to the size — and especially, the depth — of an SLR camera. Removing the reflex mirror still provides potential for space and weight savings, and Sony has taken good advantage of this. Most obviously, the drive mechanism that raises and lowers the reflex mirror in a traditional SLR isn’t needed. The translucent mirror design also provides other opportunities to optimize component placement. As one example of this, Sony has increased the angle of the translucent mirror, so that instead of directing light directly upward at a 90 degree angle as it would for a viewfinder prism, it is actually angled upward and slightly forward, allowing the autofocus sensor to be moved forward, providing more room for the electronic viewfinder assembly directly to the rear.

You have right, a isolated SMPS is used. The Microchip solution presented above will not work properly because of the ESP Module power requirements.

“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.

The skin depth varies with the magnetic permeability of the material. Iron for example reacts at very low frequencies, so much so that it becomes useless for wires at 50 Hz.

No, he is using a MC3041 to drive a BT137 which can handle 8 amps continuously (if properly heatsinked).

The control circuit for the 12V/24V can be as simple as a MOSFET and don’t even need to be isolated if you know what you are doing. Because you are using a regulated supply, the same heated bed can be used at different countries with different voltages. The safety regulatory stuff get you covered as 12/24V are considered to be low voltage.

Rather than rest after establishing products in every major sector of the interchangeable lens digital camera market — APS-C SLR, full-frame SLR, and most recently single-lens direct view — Sony is boldly striking out to create yet another category with the launch of its very first translucent mirror cameras. The main goal of the new design: achieving unprecedented autofocus and capture speed from an APS-C sensor, interchangeable-lens, consumer digital camera. Comprising a new SLT series, the Sony Alpha SLT-A33, A55, and A55V are closely related cameras sharing the same basic design, with only a few internal features as major differences.