This robot uses AI to find Waldo, thereby ruining Where’s Waldo | 25 Amp Circuit Breaker

> and some apartments are fed with 208V 3-phase, which provide three phases of 120V to neutral, or 208V phase-to-phase.

As you said yourself, low current. There is good reason to worry about mains power. The most common breaker is 15A, and that is about 15 times what is needed to kill you. It won’t trip right away either, unless it is so old and weak that it needs replacement anyhow.

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While not quite as light as the Olympus E-420, which lacks an in-body image stabilization mechanism, the Sony Alpha SLT-A33 is certainly in the same ballpark. The A33 weighs 17.3 ounces (1.08 pounds, 492g), with battery and flash card (but no lens), while the Olympus E-420 weighs 15.7 ounces (0.98 pounds, 445g) loaded but without a lens. The lightest SLD, Sony’s NEX-5, weighs just 17.7 ounces (1.1 pounds, 502g) loaded and with its kit lens attached — just 0.4 ounces more than the A33 body without a lens.

Retired engineer, 71 years young. Computer builder and programmer. Linguist specialising in language acquisition and computational linguistics. Interested…

True enough; This hack goes back decades floor finishers who have large floor sanders use this hack to run their large sanders.

I do not recommend diy 120/240 volt AC in this application. While you are correct that the higher voltage allows lower current draw, you are not proposing limiting the current, which can be very dangerous. If your hands were wet with sweat, you would act as a lower resistance path to any available ground you might be touching. In much the same way a hot dog will cook with 120 AC poet applied to each end, you will do considerable damage to your skin, muscle, and fat tissues along the current path. Use DC power, a larger wire, and maintain the safety margin. One trip to the ER will buy many hundreds of meters of wire and plenty of DC power supplies. Oh, and by the way, I’m an electrical engineer.

LOL– I stepped into doo-doo deep enough to over top chest waders, I’m over six feet tall, so that’s deep doo-doo. First I was surprise to learn that the heated beds weren’t heated by line voltage, IMO that’s a no brainer. Appliances across the word use line voltage to produce heat with no shock hazard present when use properly. Getting back to the deep doo-doo. Hackaday does present instruction posts. Line voltage is useful resource that is avoided because of irrational fear. I’m calling irrational because the fear is due to ignorance. I suggest Hackaday create instructional post on how to use line voltage in a way that’s safe to life and doesn’t cause property damage when something goes wrong. Peer reviewed studies and guidelines information is preferred.

You likely encountered a shared neutral between more than one circuit. You have to switch off the breakers for all the circuits that share the neutral.

The varistor’s absorption of the transient energy during a surge event produces localized heating within the component, which eventually leads to its degradation. If left unprotected, the degradation of a varistor can increase heating and thermal runaway. As such, a growing number of varistor-based surge-protection devices offer a built-in thermal disconnect function. It provides added protection from catastrophic failures and fire hazards, even under extreme circumstances of varistor end-of-life or sustained overvoltage.

Leaving their advanced capabilities aside, the Sony A33 and A55 are also remarkably compact cameras. As we’ve noted elsewhere, because the mirror in the camera isn’t used to form a viewfinder image, it can be mounted at a steeper angle than normal, removing some thickness from the camera body as a whole (the flange-sensor distance must obviously remain the same, but there’s more room in the body for the shake-reduction system and other electronics), and the space normally required for the mirror drive system could be trimmed from the sides. As a result, the body is noticeably compact.

Just reach for the “Flame Wrench” while working on a press, in a corrugated box plant. Within the next two minutes, you’ll know how many fire extinguishers are in that building. Box dust and the old, grease based, Letterpress ink was always a major concern when you were doing the repairs and needed to use a grinder, torch or welder, etc..