Microsoft announces Xbox One keyboard and mouse support with Razer partnership | 220v Contactor Relay

I don’t specialize in installing dishwashers or washing machines, so please don’t call me about them. You’re better off finding a plumber.

Sources: licensed mechanic-level electrician Joe Amato; licensed master electrician Johnny Goudie, owner of John Goudie Electric in White Plains, Maryland; master electrician and electrical contractor Al Hildenbrand, owner of Al’s Electric works in Minneapolis, Minnesota; Dmitri Kara, senior executive of London-based Fantastic Handyman

Agreed, the component is under rated from the start. If you look at a datasheet from a 25A SSR from a better company you will find something like de-rating curves which really show that as you move from the ideal conditions (20C temp, infinite heatsink) you should only use a smaller load. It is pretty easy to reach a limit of half the max load in normal conditions.

My situation is a good example. I just purchased a new house and unfortunately it does not have a garage. Until I get the garage built in the Spring with a NEMA 14-50 outlet, I’m going to rough it with L1 at 120V/15A.

If I find a warm circuit breaker, I take a logical approach. First, is there a good reason for the circuit breaker to be warm? A 240-volt appliance like an air conditioner will definitely warm up a circuit breaker while it’s operating. No problem there. The image below shows a warm circuit AC circuit, but in this case, I do care about the temperature readings. This circuit is only about 8 degrees warmer than anything else in the image. This is not a significant difference, and it makes sense.

The Sony Alpha A33 lacks one feature found in the A55V (the only version of the A55 that’s sold in the US market) — a built-in GPS receiver. It’s still possible to geotag images and movies from the A33, but doing so will rely on an external GPS logging device and PC software that can backtrack to calculate the location at which images and movies were shot — not nearly as seamless a solution as the A55V’s ability to geotag images and movies straight out of the box.

Oversizing switching gear is good to some point but instead of relay withstanding surges I would prefer breaker that would protect everything.

If you can power the logic side with some +5V derived from mains, there is no point keeping the optocouplers, right? Of course, the ESP would need to be programmed when unplugged from mains A/C, but with OTA, it should be possible to control it all wirelessly once the initial firmware setup is done, even more so with LUA where telnet over wifi can be used once initial setup is done. So now, what kind of circuitry is needed to hash mains A/C to +5V DC (or even better, directly +3.3V)? What’s in a commercial USB adapter? Greg

Michael Ashbaugh writes technical analysis for MarketWatch and is editor of MarketWatch’s "The Technical Indicator" newsletter.

Just curious, what size pump do you have? The Sonoff claims 10A per channel, but my 1HP pump needs a 40-50A relay to safely deal with cold-start current. Unless the relays are overspec’d I’d be worried about literally burning out those contacts pretty fast.

Terminals 4 and 6 are used for capacitors and/or condenser fan connections and have no electrical significance to the starting relay itself, as shown in Figure 1. In fact, terminals 4 and 6 are sometimes referred to as “dummy” terminals and are simply used for wire connections.Figure 2 shows how a potential relay is wired to a capacitor-start/capacitor-run compressor motor. Notice that the relay coil is wired in parallel with the start winding and the start capacitor.

This. An isolation transformer can be a very useful thing, but also very dangerous. If you touch ONE end no problem, but if you touch both ends you will get cooked and the RCD will NOT trip. Or more directly: An isolation transformer does NOT allow you to switch off your brain! And NEVER connect a scope to such a transformer.