What Most Techs Get Wrong About Wire Sizing | 2017-09-18 | 220v Contactor Relay

Have to be ohnest I would never ever consider a SSR for such an application even if it was a genuine unit form a reputable supplier. this is a perfect example where a relay should be used, tried, tested and ought to fail somewhat gracefully if it came to it. Not snarking at the OP, but any situation I have used an SSR its been massively over-specced for the load im driving, i dont think I could sleep well at night with an SSR controlling tens of amps at hundreds of volts.

I came here to post those two points! The corollaries to 1) are that should something go wrong, you have a chance if there is someone else there who knows CPR. I like mandatory CPR training for lab workers because of this. AEDs are good too. Rules against playing with things that can shock you while working alone are also good, but much harder to follow–I’ve spent decades working alone in research labs. CPR fails way more often than not, but electrical shocks are an important exception to that rule. And you almost got the extra credit for correctly spelling arrhythmia.

“International” power supplies usually are specified for 100V (Japan) to 240V +/- 10%, i.e., 90-264V.

Yup, switched off but still plugged in, that way the case is still earthed. Assuming a sensible 3-pin plug, or whatever the hell they do in places with just 2.

The contacts therefore return to their normally closed position by spring power as the motor coasts to a stop.

The two 120V legs are *in phase* with each other. Residential power in the US is single phase, sometimes called split phase because they’re both 120V relative to the center tapped neutral.

Older light fixtures won’t necessarily work with energy-efficient CFL and LED bulbs. If you want to stay away from incandescent light bulbs, you might need to replace the whole fixture.

The U.S. benchmarks are approaching the unofficial start to summer amid characteristically range-bound, and slightly sluggish, price action.

It works, but the losses are significantly higher, and if you’re drawing much power you’re going to need heavy, expensive low-voltage sides on both transformers. In a pinch, fine, but if you’re going to be buying them it’s better to spring for a single transformer.

FreeSync is available on the NU8000, Q6FN, Q7FN, Q8FN, and Q9FN. Once you’ve installed the latest firmware on one of those TVs, you can find it under Game Mode in the settings menu.

Meanwhile in my house (uk) we have a street lamp time switch with a single pole switch that looks like it was designed to handle 30A. It is beautifully engineered from brass that increases the on period as the days get shorter, I felt bad hacking it so that it would turn on my water heater for an hour twice a day, a job it has been doing for 17 years now without incident. Electromechanical is by far the best way for high current loads at any voltage as fatcas I’m concerned.

While the Sony A33 and A55′s viewfinder display led to a bit of a learning curve for tracking fast action, its buffer-clearing speed is an ongoing issue. The A55 can capture shots with amazing speed, but once its buffer is filled, things slow down dramatically. The A33, for its part, has a smaller buffer, but it takes less time to clear. The most irritating point with the A55 was that it seemed to take forever before it would let me look at what I’d just shot. This is certainly more of an issue for a relatively inexperienced user than a pro sports photographer, but I often found myself wanting to check out what I’d just shot before the next action sequence started so I could note and correct for any problems in my shooting style. If I’d filled the buffer, though, it took upwards of 15-18 seconds before I could even view the first image on the LCD — and a good while longer before the buffer was completely empty and the camera was back to its maximum burst-length capacity. Shoot RAW+JPEG and it takes 32 seconds to clear a maximum of 18 images, while the A33 only captures 7 images and takes 12 seconds to clear. Advantage A33.