Tom Baker is turning his long-lost Doctor Who movie script into a novel | 19mm Momentary Push Button

If a high-frequency current is large enough to be immediately painful, it’s large enough to immediately burn you, which is why hooking a tesla coil to a doorknob is rather dubious. It hurts, because it really hurts.

I have been hit HARD by one leg of 440v, 3 Phase power running the 2.5 HP motor of industrial manufacturing equipment. I was on a cement floor, and wearing combat boots at the time. I am sure that helped, but my right arm and shoulder hurt with a strong, but dull ache for over a week afterwards.

If you use 24V for 120W, you only need 5 amps. That’s not much. A good mosfet shouldn’t even get warm at 5A, and you don’t need very fat wires.

*Using approved LO/TO procedures which include verifying the energy sources are removed/disappated and safe

You know very well, I hope, that for dimming you need to use a random phase optoisolator not a zero-crossing one. Like MOC3020/21 for example. This is in the command/trigger circuit for the Mains swiching Triac. Now show us your Relay driven dimmer beauty concept. Is good to learn something new everyday.

Flake, along with Sens. Chris Coons (D-DE) and Cory Booker (D-NJ), attempted for the second time to schedule a floor vote on the bill protecting Mueller on Wednesday, but it was blocked by Sen. Mike Lee, who argued that the legislation was unconstitutional (a longstanding conservative argument, explained by Vox’s Tara Golshan here). The bill would ensure that Mueller could only be fired by a Senate-confirmed DOJ official and enable the special counsel to review any firing.

So here follows the first in a series on how to approach electronic devices containing high voltages, and live to tell the tale. By “high voltages” we mean anything up to mains voltages, and those directly derived from them such as the few hundred volts rectified DC you’ll find in a switch-mode PSU. For multi-kilovolt EHT you’ll have to wait for another article, because that is an entire subject in itself. We’ll mention these higher voltages in passing, but their detail is best left for a Hackaday colleague with more pertinent experience.

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.

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The operation of the potential relay is based on the increase in back-electro-motive force (back-EMF) or a bucking voltage that is generated across the start winding as the motor increases in speed. The large metal mass of the motor’s rotor turning at high speeds with motor windings in close proximity has a voltage-generating effect.

Attack of the giant hand? That’s what we called these shots when we took them. Despite the disparity between the size of my hand and the camera body, the grip was still fairly comfortable.

I first thought we were about to see the actual moment when it was about to blow. But this is post mortem autopsy.