Looking Mains Voltage In The Eye And Surviving | Lrd12 Overload Relay

continuing akismetuser212339447″ Using a mechanical relay for your thermal control _may_ make you crazy with the clicking. If you think you can take the madness, keep an eye on the make/break current rating, and the lifetime switching at the design current. Switching current and voltage is often far less than carrying current, and electrical contact life is short compared to mechanical life (Switching at zero crossing will help). Also note that failure mode of relays is possibly contacts fused closed – design with safety in mind, and have some sort of feedback. Something like a thermal cutoff fuse?

Temperature swing in the water heater may be about 50K, incandescent bulb filament temperature swing is closer to 3000K. I doubt there is much variation in the resistance of the water heater’s heating element

Also, worth noting is that many cheap supplies out of China are designed for 110V/220V, +/- 10%. Consequently they’re designed to 121V/242V. For those of us in 240V areas, so in perfect conditions, they’re operating at the very top end of their specifications.

Yes you can use those high voltage safely, BUT your typical DIY people don’t even bother to read or understand datasheets. These people need the proper training, but aren’t likely to be bother to go beyond the typical monkey see monkey do watching youtube and think they know it all. I have seen enough of bad layouts of the average projects that doesn’t even understand that the creepage space between the primary and secondary side of an optoisolator aren’t meant to be for routing!

The QD terminals are totally fine as long as you have a ratchet crimper, which I saw you said that you did.

MOVs tend to degrade gradually after a large surge or multiple small surges. This degradation leads to increasing MOV leakage current; in turn, this raises the MOV’s temperature, even under normal conditions such as a 120-V ac or 240-V ac operating voltage. A thermal disconnect adjacent to the MOV (Fig. 4) can be used to sense the increase in MOV temperature while it continues to degrade to its end-of-life condition. At this point, the thermal disconnect will open the circuit, removing the degraded MOV from the circuit and thus preventing potential catastrophic failure.

I walked in on instrument installation day and began the burn in test of running the halogen fixtures at 100%, then bringing it down over the course of 30 minutes to determine if we had a bad SCR dimmer.

well, originally they were 2 kW transformers (or at least from microwaves that are rated to 2-2.5 kW), and on secondary is wounder stranded thick wire (diametar around 7-8mm)… enought power to melt nails with 3-4 mm diametar…

Translucent (pellicle) mirror. Undoubtedly the biggest story of the Sony SLT-series cameras is their use of a translucent mirror. Also known as pellicle mirror, this works by allowing most light to pass through to the imaging surface beneath, while a small portion is reflected for other purposes. Sony is not the first camera manufacturer to use a translucent mirror in an SLR-style camera, with the manual focus Canon Pellix film camera from 1965 taking that credit. The Pellix was followed by a handful of other pellicle mirror-based SLRs from Canon, Nikon, and Mamiya, largely designed for professional photographers, and manufactured in very limited production runs. It wasn’t until 1989′s Canon EOS RT that the first autofocus pellicle camera was released, followed by the EOS-1N RS in 1995. Fifteen years later, Sony has become the first company to resurrect the pellicle mirror for use in an interchangeable lens digital camera.

But at the end of the training it says “you can ignore all of this if you are troubleshooting”. If you are afraid of live circuits, stay at your desk where it is safe…

The nostalgia for “classic” miniature consoles isn’t ending anytime soon, either: Sony just announced today it’s making its own PlayStation Classic console. The tiny PS1 will come with “20 genre-defining titles,” and it’s set to release this December for $99.99. Also coming this winter is the Sega Mega Drive collection on the Nintendo Switch, and the trailer for it was published today.

There are notable advances in interior quality and function, most significantly with the dash getting a complete overhaul that includes better materials, layout and an eight-inch screen operated by buttons and touch as standard. It’s both smart and reasonably intuitive, albeit slightly short of some of the slickness of VW’s various systems. As is common in the class, Toyota has expertly put the best materials where you are most likely to see and touch them, with hard, basic plastics mostly hidden in corners of the car.