Kibbles & Bytes Blog

We’ve had two 90-degree days here at the office. There is contention about whether the heat is good or bad. I personally like it. I think riding a bike on a nice hot day is one of the best things ever, especially if you can jump in a river or lake afterwards. This hot weather hopefully signifies that summer is either here or quickly approaching, and that means that we should start experiencing thunderstorms soon. With that in mind, I thought I’d take some time to refresh you all on what lightning is as well as safety precautions for both you and your electronics.

Lightning itself, the bright bolts you actually see, are discharges of static electricity. Technically speaking lightning itself has no temperature because lightning is moving electrical charges, which have no temperature. But flowing charges (also called current) can heat up the medium through which they travel. The more resistance, the more heating. Air is a poor conductor, so current flowing through it generates a lot of heat. The bolts you see are actually air being turned into plasma, and it is very hot. How hot? It’s actually hotter than the sun. The plasma can reach around 30,000 K or 53,000 F. The surface of the sun is “only” 6,000 K. In fact despite the high voltages and current involved with lightning, humans are most at risk from electrical burns. Death from electrical shock usually only occurs when the current through the body is between 0.1 and 0.2 amps. Lightning is going to generate far more current than that. These kinds of shocks aren’t generally fatal because the muscular contractions are so severe that the heart is forcibly clamped shut thereby protecting it from ventricular fibrillation (the mechanism that actually causes death from electricity). However, such current may result in severe burns.

In terms of protecting yourself from lightning, the best thing to do is get indoors if at all possible. You may have heard that a car is also a safe place with respect to lightning. This is true, but there are some caveats. First, why is the car a safe place? If you took the average car, and stripped away all the plastics and materials, you’d basically see a metal shell. It’s this shell that ultimately protects you by acting as a Faraday cage. The current is absorbed and dissipated by the frame of the car. Sometimes, depending on conditions, the lightning will actually jump the rubber tires and go into the ground. This would make your car more like a grounded Faraday cage, but grounding isn’t necessary for it to work. Obviously a car isn’t a perfect Faraday cage, so precautions should still be taken to maximize your protection. You should stop the car, shut it off and roll up all the windows. You should then rest your hands on your lap and not touch anything else in the car.

What about electronics and appliances? When I was a little kid, my dad had a police scanner and my mom got him a big external antenna for it. We mounted the antenna on the roof of our house, and I remember that we then drove a long rod into the ground and connected it to another rod atop the antenna. My dad explained it to me back then that this was so if lightning wanted to strike, it would hit the rod and be directed down into the ground safely, rather than into the house, or into his scanner equipment. We never got struck by lightning there, but I do remember helping him install it.

You’ve likely seen lightning rods on any tall structure, but you’re less likely to have used or installed one yourself. For protection of home electronics, we often use lightning arresters, also called surge protectors. These simple but effective devices are very cool. They’re usually placed where wires enter a structure. Normally the relatively low voltage power flows from the wires outside to the inside through the arrester. There is a secondary channel in the arrester that has a very high resistance, so normal electricity won’t flow through it, but lighting will be high enough voltage to cause that channel to conduct. This channel is typically routed to ground. So the lightning, or surge, will come in on the wires, but then be redirected away from the sensitive equipment inside the structure. The difference between a lightning arrester and a lightning rod is that the rod is meant to absorb, or even attract, a direct strike. The arrester only deals with the high voltage once it has entered the power grid or telecommunication network.

As always though, it’s important to remember that no protection mechanism is 100% failsafe. Especially when dealing with very high energy things like lightning, the strategy is generally deflect and redirect rather than suppress and neutralize. The only failsafe method to protect your electronics from lightning is to unplug them completely.

Bonus tidbit: Now that you know a little bit more about the composition and nature of lightning, I can more easily explain what causes the thunder that follows. The current of the strike so instantaneously superheats the air into plasma that it expands explosively, causing the thunder we hear.

I got back to Vermont and on my list was putting in some HomeKit gear for this house. I chose Philips Hue for lighting because I may want to take it with me to another location which is why Philips might be the choice for those that are renting or transient.

Right now, the best bargain in Philips Hue is the starter kit that includes the hub and two white bulbs. Grace was laughing at me because I also bought some color lights, light strips and other cool Hue gear. But in this article I want to go over the initial set-up of a Hue system and how to group your lights.

First step is to take the hub and connect it to your router. I have an Airport Extreme sitting on a shelf with a growing collection of hubs (Arlo, Kevo and now Philips). Fortunately, I haven’t filled up all the ethernet ports on the Airport Extreme so after running the power cable I just plugged in the ethernet cable to the Airport. The next step is to screw in the light bulbs. In this case, it took a couple of aging hippies to screw in a bulb.

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Once you have the bulbs in place make sure they are switched on. Next, download the Philips Hue app from the App Store. Once you have the app, you can have it search for the hub. Once it finds the hub you are set to go. Press the button on the hub and the app will find your newly installed bulbs. You are done and you can use the Hue app to control your lights but what you really want is the Apple Home App and Siri to control them.

One thing to be careful about is naming. I started out naming my lights hallway for the hallway lights but Siri, HomeKit and Hue will be confused if you have two hallways or like me two houses with hallways so Grace and I spent a little time arguing about what the most appropriate name should be. For Siri or for Amazon Echo you want to make these names easily understood and usually one word.

So your lights are now connected and you can dim them and turn them on and off with the Hue. Next, in the settings section of the Hue app activate HomeKit and Siri. This will allow the lights to be controlled by the Home app. Since I also have an Amazon Echo in my house, I also went to the Alexa app and had the Echo also discover the lights. Once this is done you have a lot of control over your automated lights. You can turn them on by asking Siri on your iOS device (or Alexa). If you have set up your Apple TV as a HomeKit hub you can turn the lights on and off remotely, too.

You can also create scenes and automations. Things like having the lights come on at sunset or off at a certain time. You can also use geo-fencing so the lights come on when you arrive home and turn off when you leave. That works great if you live alone but is a bit annoying to your housemates otherwise.

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So, I put in five Hue colored lights in our living room which actually used to be the Small Dog offices before we outgrew it. It sort of got the name “west wing” because it was west and no relation to the White House. So, as I was adjusting these lights I found that it was a real pain to have to adjust the color of each light individually. I could tell Siri “Turn west wing lights to purple” and that would work but if I wanted to fine tune the colors I needed to group all the lights together so they act as one light. I could not find out how to do this. I googled, I downloaded 3rd party apps but I really wanted Siri to control them as one.

So, I was up at our S. Burlington store and asked Erich to demo some Smart Home gear in our new Home Automation section. By the way, if you have not been into our S. Burlington store lately you should check out all the cool renovations that were done while I was in Florida. Anyway, as Erich was demoing he casually mentioned grouping. I said “whoa!” and had him show me. The googling was wrong, there IS actually a very easy way to group your Hue accessories if you are using HomeKit.

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To group your accessories you simply go to the home screen of HomeKit and press on one of the accessories, i.e. a light. That gives you the control screen for that accessory. You can dim and turn on and off and adjust color for colored lights. There is also a “details” button. Press that button and you have more options including naming the light, assigning it to a room, toggling whether it is included in HomeKit favorites and if you scroll down you can group it. Clicking on “Group with Other Accessories” button will allow you to choose which lights go together. You can then name that group and you are ready to go. Instead of five individual lights, I now have one button for all the west wing lights.

I have a lot of fun setting up Hue lighting and it is very simple and very versatile but thanks to Erich for solving my grouping dilemma!