Google’s Night Sight for Pixel phones will amaze you | 19mm Momentary Push Button

people remember “the good old days” and they forget all about the horrible accidents and fires and massive death that came from ignoring fire regulations

AC does make you clench. I was unable to let go of some AC transformer wires once for about 10 seconds before I shook free.

You are right, FR-4 has a glass transition temperature of around 120°C, so if you heat up your traces above that, and take into account the mechanical stress from expanding copper traces, delamination is something waiting to happen sooner or later (especially if you design corners in your traces). Add to that the fact that you usually don’t measure the temperature directly on the traces to regulate input power, you could go way beyond 120°C in your copper traces. I don’t think a lot of DIY guys actually know that there would be high-TG materials on the market better suited for PCB based heater applications…

You can share neutrals among, say, receptacle circuits, if you make sure that there’s some kind of disconnecting means that opens all the conductors associated with all the circuits that share a neutral. That might be a multipole breaker, or it might be handle ties that physically tie breaker handles together, forcing all to trip if any trip.

I don’t know where do you see low voltage traces close to mains voltage. Trace from R8 to the opto is 2.64. How far do you think it should be to meet your standards? Conformal coating is telling you anything?

I had the same shock at 8 years old I put my finger in a lamp socket with no bulb, Living in UK I was treated to 240v. I have never had a mains shock since (thankfully). i have had lots of other shocks though mainly non discharged capacitor’s/

I use a variety of a/c and dc fostek ssrs. I have yet to have a problem, but i use them in circuits where 50% of their rated current is the absolute maximum they will ever see.

Voltage TransientsVaristors feature high durability, which is essential for withstanding repeated high-peak pulse currents and high-energy surge transients. They also offer a wide voltage range, high energy absorption, and fast response to voltage transients. Peak current ratings range from 20 to 70,000 A, while peak energy ratings range from 0.01 to 10, 000 J.

And use a power circuit with a differential circuit breaker so if you touch live wire it will disconnect.

What about putting a uC in SSRs, so you can ask the think if it’s an original part or not. Propper encryption needs to be implemented of course.

We drive about 30k miles/year, lots of long trips. After a trip, we usually pull in with 25-50 miles of range remaining. No problem – charging to the normal 80% is < 7 hours.

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