The buyer’s guide to electric-car charging stations | 220v Contactor Relay

Anyone know a good source of information for dummies on electromagnet math? I’d love to build one of those electro magnetic pan brakes, but blindly connecting 240VAC to a coil scares me.

The customer wasn’t pleased. I had obviously done something wrong. I showed them the paperwork with the specifications showing that the input to the dimmers was to be 20 amps. They insisted that their electrician knew better than I did.

It also doesn’t hurt to spend a bit more. I found a 40A SSR, well-known Japanese brand, from a reputable distributor, for $30. That said, I might easily have made this same mistake; thankfully I won’t have to learn the hard way (this time!).

Creepage to the mounting screws is one issue and that fuse crowed by traces at mains potential is just bad design.

In my experience, the more people know about electricity, the more cautious they are. And the more they have to deal with dangerous voltages, the more cautious they are. With few exceptions, most Youtubers you see doing dangerous stuff online have no idea what they are doing. Speak to a decent electrician and you’ll see they work more safely than most engineers and thousand time safer than amateurs. We don’t really need electrical cowboys showing off how dangerous the stuff they do is.

Overall though, you’re just talking about increased RMS voltage allowing more current; the more current the more burn, heart arrhythmia and neuromuscular effects.

If you’re totally stumped on a page of Where’s Waldo and ready to file a missing persons report, you’re in luck. Now there’s a robot called There’s Waldo that’ll find him for you, complete with a silicone hand that points him out.

There are many applications that don’t require 10A switching. As long as you are aware of the power limit of the device, there’s no harm in making a version for 1A or less.

A better choice is to spend a few hundred dollars to have an electrician install a dedicated 240-volt circuit – like those used for an electric clothes dryer – to take advantage of what’s called Level 2 charging. This can replenish a depleted battery in around four hours. You’ll also need to purchase an external Level 2 charging unit, which is also called the electric vehicle service equipment (EVSE).

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.

Your friend reminds me of a domestic main voltage electrician that would test with the back of his hand. He’s dead now.

But they’d have to be in the same phase for it to work. If they’re in opposing phase, they’ll just push and pull against each other.