The Expanse is being turned into an RPG | Circuit Breaker Parts

I started my hacking adventures decades ago with vacuum tubes and high voltages, and have to say that this is an excellent and important article. I’m not sure of the country of the author, but one piece of translation for those just getting started. The “Residual Current Circuit Breaker” here in the U.S. is called a “Ground Fault Circuit Interrupter”; but, provides the same protection. Another more recent protection innovation is called the Arc Fault interrupter and actually contains DSP type circuitry to determine if a dangerous arc is present on the line. Flipping a light switch or running a small motor creates an arc; but, the AFCI can tell the difference between that source and a frayed power wire that could overheat and start a fire. The largest voltage I’ve ever worked on was an amateur radio linear amplifier that ran 2600 VDC @ 600 ma for the finals, which brings me to the main point of this post. One additional rule: Always keep one hand in your pocket or one finger hooked in a belt loop. While it makes handling equipment more tricky, it keeps the power from having a path across your chest, which is also across the heart and lungs, which are electrically operated and can be severely damaged or stopped. BTW, I love the image of the sign/sticker in this article which hit’s the nail right on the proverbial head.

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.

After which he had an excuse to take the afternoon off and he repaired to the pub for “a feed” of Guinness!

Waterjet – Eh? Are you on heavy meds/drugs or just plain stupid? What the fsck has the optocoupler to do with the load? It simply triggers the BT137 which is the triac that handled the switching of the load.

The saw cuts in both directions, one person pulls, and the other slightly lifts and the saw cuts. then the other person pulls and the opposite person slightly lifts and follows the saw. Each person has a pull stroke and a less strenuous return stroke.

In some cases, contractors have stated that certain municipalities are requiring that conductors be sized based on the breaker size instead of the MCA. This is not uncommon, but it is usually a matter of a respectful conversation about the above NEC articles. The “authority having jurisdiction” or AHJ is responsible for interpreting the code, and they can make any standard they see fit. While certain local legislation may supersede the NEC with additional regulations, the NEC is a nationally recognized standard throughout the U.S. It is rare that a building department will ignore entire articles of the NEC when it is brought to their attention in a respectful manner.

I found the Sony A33 and A55′s AF tracking to be very fast and pretty accurate; almost too fast in some cases: If I let the central AF point wander off the subject for a fraction of a second, focus would quickly shift to the background. Many of the missed-focus shots I took were the result of this problem, versus the camera not being able to track focus quickly enough. Some high-end DSLRs have settings in their autofocus systems to adjust how quickly they respond to momentary loss of the subject. (Either from the AF point drifting off the subject, or for some interfering object passing between the subject and camera.) If Sony were able to add this capability to the A33/55, it could go a long way to reducing the number of missed shots, at least based on my experience.

Agreed, this is a house fire waiting to happen and your insurance co. won’t give you a cent if an investigation points to this homecooked thing as the firestarter. There are numerous commercial alternatives which are small enough to fit in a junction box _and_ are UL/FCC/CE approved. Granted, they aren’t as cheap as the ESP module and the triac described here, but in the end, most cheap alternatives to switching powerful currents turn out to be very expensive after all.

A fun read is the Boeing’s space station power system document that describes the DC power system on the ISS: http://www.boeing.com/assets/pdf/defense-space/space/spacestation/systems/docs/ISS%20Electric%20Power%20System.pdf

I think every power MOSFET in my box, most of them from reputable sources, have packages rated below the die.

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