Stay Ahead of the Storm

A couple of years ago, my daughter and I went to the X-Games in Austin for the third year in a row. We were under flash flood warnings so I was hyper-aware of the weather. The atmosphere was unstable and there were popup showers in the area. As we were watching the Skateboard Street competition, we could see a big bank of black clouds gathering in the distance. I was hoping it would go around us but I was monitoring it closely on my iPhone weather app, WeatherBug. My main concern was lightning. WeatherBug has a lightning app within the app called Spark. It uses real-time lightning data and your GPS, and it tells you how far away the closest lightning strike is to your location. Unfortunately, it didn't work when I needed it most. I knew there was lightning in the not-too-far distance but Spark just gave me a blank screen.

The X-Games is very good about monitoring the weather and making the right call. Just the day before, the entire park was evacuated to our cars while we waited out the weather. So I felt okay about staying to watch Skateboard Street even though I could see the gathering clouds. But when the announcement came over the PA to evacuate the grounds and retreat to our cars, all hell broke loose. In about less than one minute after the announcement, the skies opened up and large drops of rain pelted the scattering crowd. Everyone scrambled to gather their loved ones and their belongings and headed for the exits. Me, my daughter, and her two friends started running for the shelter of my car in the parking lot about half a mile away. Before we could go ten meters, the wind picked up and that's when I really started getting concerned.

I grew up on the Texas coast and I've lived through several hurricanes, so I feel like a have a pretty good grasp of the power of hurricane-force winds. That day at the X-Games, it felt like we experienced close to hurricane-force winds. At that point, my concern shifted from lightning to wind. There were so many tents, cranes, and structures that could be blown over that I kept my head on a swivel, trying to anticipate what would happen next. At the same time, I was trying to keep my eyes glued to my daughter and her two friends, coral them, and guide them to the car without getting lost or hurt. Once I made eye contact with them, we all ran towards the parking lot. About 10 meters into our mad dash, the three of them decided to stop and seek shelter under a small pop-up tent along with about 30 other people. I understand why they did that; large drops of rain were pelting them, soaking them to the skin, and everyone else seemed to be doing it. But I wheeled back around and urged them to keep running for the car. Reluctantly, they did.

We ran another 300 meters into the paddock where they house the EMTs and ambulances. Fortunately they had opened the gates to these normally off-limits premises. We were herded in there with dozens of other people, all of us soaked to the skin. I pulled my cell phone out of my soaking wet pants and pulled up the Sparks app. It finally worked. There was lightning within six miles.

I never felt like our lives were in danger, but I did feel like the situation could have turned as quickly as the rain and wind was unleashed upon us. While we were waiting for the all clear signal, I had time to reflect on what had just happened, and how we could have been better prepared. Lessoned learned:

1. Knowing the weather was unstable going into the event, I should have not waited until the announcement to evacuate; I should have gathered the troops and started moving towards the parking lot when the dark clouds were approaching.
2. By the time the bad weather hits, it's too late to make a plan. I should have prepared the girls for the possibility of evacuating before it started raining and gusting. When the weather hit, it was pandemonium. People were running in every direction and we could easily have been separated. In fact, I witnessed one mother desperately calling out for her child, from whom she had been separated during the event. I was torn between wanting to help her and feeling the tugging responsibility to the three girls. Not knowing what the child looked like, I decided that there was nothing I could do at the moment to help here. Later on, I saw her and her child in the paddock.
3. What I remember most vividly is how loud it was. The howling wind makes a surprisingly loud noise, making it almost impossible to give or follow instructions. If I had a do-over I would have told the girls that, in the event that we were separated, we would meet at a designated spot.

230, 231, Whatever It Takes

Question: My understanding is that if you have a 230V, 3-wire device like a motor and you feed it two 120V hots and earth, then it is running at 208V.  Alternatively, you can use a step up transformer and feed it one 230V hot, one neutral, and earth and it is running at a full 230V.  Is there a scenario where this device is fed with two 120V hots and it is running at 240V? For example, if both 120V taps come off the same phase leg (or if they come off different phase legs?) Or is 120V + 120V and earth always 208V?

Answer: Yeah, it can be confusing. Here’s the lowdown. Most likely your 230V device is European; otherwise, it would be a 208V device or a 240V device. In Europe, the hot-to-neutral voltage is 230V (except in the UK where it is actually closer to 240V, but they still call it “230V.”) So the three wires on this device are probably one hot, one neutral, and one earth conductor.

In North America (and other parts of the world), if you feed it using two hots from a 3-phase system, it will get 208 volts. 

On the other hand, a lot of homes have “split-phase” service, meaning the phase-to-phase voltage is 240V and the phase-to-neutral voltage is 120V. That’s not a 3-phase system, but it allows you to use 120V for everything in your house except the washer and dryer, which are probably 240V devices. Also, some venues have “delta power,” which means the phase-to-phase voltage is 240V, but one of the windings in the transformer has a center-tap, which allows you to pick off 120V from phase to neutral. Delta power is more common in industrial parks where they have light manufacturing because they use the 240V for heavy machinery like drill presses, punching machines, CAD/CAM, etc., but they also have 120V for their computers and microwaves. You can identify delta power by the orange marking on the “high” leg, and it’s important to know that the voltage from the orange leg to neutral in delta power is 208V. That’s the only time you’ll find 208V from phase to neutral in North America, which is why is has to be identified by orange as a warning to users. 

Lastly, most 3-phase generators can operate in “single-phase zig-zag” mode, which gives you 120V from phase to neutral and 240V phase to phase. 

So there are a couple of different ways to get 240V in North America but it depends on the service.

Help! I Can't Math

by Richard Cadena

Don't tell me that you are just aren’t good at math. I won’t buy into that. On the other hand, if you say that you’re not interested in investing the time and effort to polish your math skills, okay, I get it. Math is not for everyone. But unless you have a learning deficiency like dyslexia, you can get good at math if you’re willing to invest the time and energy. Here’s how.

If you really want to understand your craft as an electrician or technician, then you need some decent math skills. The math is not hard if you practice it. Ohm’s law and the power formulas are just basic algebra. If you break it down into small steps, it’s really simple.

1. What is the question? That may seem like a trivial step, but it’s so important to identify the unknown variable. Write it down and make sure you know the units of measure. For example, if you’re trying to figure out the current draw for a particular fixture, then the unknown variable is the current I, and its units of measure are amps. The reason you should know the units of measure is because that sometimes can give you a hint about how to solve the problem. If, for example, the unknown variable is speed, its unit of measure is miles per hour. You can literally solve the problem by dividing the number of miles traveled by the number of hours it took.
2. What do we know? Identify the knowns or givens by writing down everything we know or are given. For example, if we’re trying to figure out the current draw for a particular fixture, we can look up the specs online and write down what we’re given, which is usually the voltage and the power in watts. Sometimes the specs include the power factor too.
3. Which formula should we use? Write down the formula or formulas for solving the problem. In our previous example (solving for the current draw), we will write down the power formula, but we need to know whether to use the single-phase power formula or the 3-phase power formula. If we’re trying to calculate the current draw for a single fixture, we’ll use the single-phase formula, but if we’re calculating the current draw for several fixtures in a 3-phase system, we’ll use the 3-phase formula.
4. Calculate the answer. Be careful to enter the right values for the knowns.
5. Evaluate your answer. Just take a look at the answer and ask yourself if it makes sense. For example, if you’re trying to figure out the current draw of a 2000-watt fixture at 208V and you get an answer of 961 amps or 0.961 amps, you should immediately suspect you made an error.
6. Double check your work.

Once you practice these steps and get really good at them, they become second nature to you and then you no longer have to think about them, they just happen like the moon follows the sun.

Gimme Three Steps (Toward Success)

I grew up with a friend who made a fortune twice. And unlike other people who have done this, he didn't go broke after his first fortune and then earn another fortune. Instead, he started a successful business, sold it, and after a time he became bored doing not much of anything, so he started another very successful company. I was thinking about him this morning because I remembered something he shared with me about himself.

When I went to visit him in California after he started his second business, Blaze Pizza, he took me to his first restaurant in the chain. While we were sampling the food and service, I complimented him on his success.

"I'm really proud of you," I said. "You've worked hard to make yourself a success."

"Actually," he corrected me, "I don't like to work hard at all." He told me that he takes a very leisurely approach to business and spends very little time in his office.

That goes completely counter to everything I thought I knew about success, leaving me to wonder what really is the combination to unlock it. I don't claim to know all of the digits, but I think I have at least three of them.

1. Great ideas are a dime a dozen. Sure, my friend had at least two great ideas. The first was triggered by a childhood memory. When we were in grade school, one of the kids in our class used to tease him about his last name. He called him Wetzel the Pretzel. Years later, when he was searching for ideas to start a franchise, he remembered that and so he started the Wetzel Pretzel chain. But clearly, a great idea is not the only requirement for financial success or most people I know would be fabulously wealthy. I once had a friend who claimed to have come up with the idea of using a vacuum cleaner hose to drive a motor with a blade that you could use to cut your hair. Only later was the Flowbee vacuum cleaner attachment for cutting hair patented. But it wasn't my buddy who patented it and reaped the financial benefits. Clearly there's more to financial success than just having a great idea. You have to take action.

2. Risk has rewards. Once my grade school friend had an idea for a pretzel franchise, he risked his time and money to start the business. Had he not taken that leap of faith, he would never have made a go of it. But I think there's at least one other ingredient in his recipe for success.

3. Location, location, location. Corpus Christi, Texas is a great place to be from, but it's not the land of financial opportunity. It's a sleepy little seaside city where we grew up, but had his family not left when he was in high school, I doubt he would have succeeded in business. He ended up in the Los Angeles area, which is where he started his first (and second) business(es) and where there is ample opportunity for success in a variety of fields. That's not the only place where his franchises could have succeeded but I'm pretty sure it wouldn't have happened in south Texas.

Whether you want to succeed in the restaurant business or in live event production, I think you need more than a great idea. You need to act on your ideas. It helps to have a tolerance for calculated risk, and be willing to relocate to where the opportunities are. Just ask Rick Wetzel.

Technology at NAMM 2018

Oscar Wilde once said that when business people get together they talk about art and when artists get together, they talk about business. So what happens when business people and artists get together? They talk about technology. 

Jackson Browne was presented with the Les Paul Innovation Award at the NAMM TEC Awards in January. When he accepted it, he talked about the first tape recorder he ever bought and how they took to the road to record "Running on Empty" in buses and live venues. Then he took the stage with Lee Sklar, Russ Kunkel, Danny Kortchmar, and Craig Doerge (the Section) and played a couple of songs. It was a magical night.

That wasn't the only opportunity to talk or learn about technology. There were a number of newly added sessions having to do with live event production. I couldn't attend them all, as much as I would have loved to, but I either participated in or attended several, including Mike Wood's "LED Technology: From Diode to Light," "Sustainability and Cost Savings in Event Lighting" presented by Mike Wood and myself, "Video Production: LEDs, Fluorescents, Automated Lighting; and Lighting Design for Video Production in the Age of LEDs" presented by Matt Ardine, Kieran Illes, David Kane, Mike Wood, and myself, "Electrical Safety for Stage and Set" presented by Alan Rowe and myself, "Video Production: Power on a Shoestring" presented by Kieran Illes and Alan Rowe, "Console Programming Workflow" presented by myself, "Media Server Programming and Pixel Mapping" presented by Matt Ardine and David Kane, and "Advanced Ethernet Networking" presented by Scott Blair, John Huntington, Kevin Loewen.

My favorite session was "Advanced Ethernet Networking" presented by Scott Blair, John Huntington, Kevin Loewen. These guys are the industry gurus when it comes to networking. Some of the notes I took during the session include...

• John Huntington said that terminating Cat6A is a "pain in the ass." He said you can use Cat5E for gigabit networks and it works fine.
• An auto IP is a way of automatically assigning an IP address to a device if it does not receive one from a DHCP server. Scott Blair said that auto IP works with sACN because, as long as the device has IGMP snooping, the IP address doesn't matter. Auto IP addresses are in the range 169.254.x.y.
• Simple Network Management Protocol (SNMP) is a protocol that allows you to monitor a network. According to the panel, there are several SNMP applications but I think I missed their favorites. I'll be researching that next.
• John Huntington recommended the Byte Brothers Real World Certifier for testing LAN hardware and cabling. I found this link on his web site with information and specs.

There is still lots to unpack from NAMM but this is a start.

The Art of Troubleshooting Like Leonardo

True story. My wife teaches spin classes at a local gym, and the other day I went to her class. Before class she was struggling with the computer that runs the audio and scheduling in the room. She couldn’t get it to work, so I thought I would help. The computer is a NUC-type, about six inches long by about four inches wide and inch deep, and it was mounted to the back of the equipment rack. All of the cables, both power and data, were routed through the locked rack, concealing their path. The monitor had an error message saying that it was not receiving a video signal. So I disconnected and reconnected the video cable at the monitor and at the computer, but the same error message appeared. Then I disconnected reconnected the power cable at the computer, thinking that resetting it might help. Again, the same error message appeared on the monitor. It must be a bad video cable, I thought. It was frustrating not being able to get into the rack to get a better look, and I was at a loss about what else I could do. I almost gave up. About that time, the manager of the gym came along and pushed a button on the computer and it came to life. It turned out that the On/Off switch was in the Off position.

The first rule of troubleshooting is to check the obvious things first. Bill Byrd used to be a technician at High End Systems. He started there shortly after serving as a tech in the Air Force. That’s where, he said, he picked up the first rule of troubleshooting. “Is the O-N/O-F-F switch in the O-N position?” That was his favorite line.

Another good practice while troubleshooting is to take pictures as you go so that you can reference them when it’s time to put things back together. We used to have to write everything down but now with smart phone cameras, it’s much quicker and easier to take pictures.

One last tip is to write down your steps as you go so that you never have to repeat your work. Last month I was troubleshooting a complicated lighting network at a major television studio. (Look for the article about it in the Winter 2018 issue of Protocol magazine.) We had run a temporary Ethernet cable to a network switch in a computer closet, so we had two cables – the main and the temporary. The system worked fine on the temporary cable but there were problems with the main cable. I wanted to rule out the cable itself, so we tested the system in four different conditions; one with the main cable connected to the main port in the switch, one with the temporary cable connected to another port in the same switch, one with the main cable connected to a different port in the switch, and the last with the temporary cable connected to the main port in the switch. So I quickly drew a table with four rows and labeled them 1 through 4. As we conducted the test, I would write down the results.

I’ve learned over the years that even a simple test like this can be interrupted or you can lose track of which combinations have already been tried. So writing it down saves time and effort. This is a technique that I learned from reading about Leonardo da Vinci, who was said to document everything his did in excruciating detail. It takes longer but in the end, it saves time.

There is a lot more to troubleshooting, and as you gain experience you will develop your own techniques. But in the meanwhile, focus on the simple solutions first, take lots of pictures, and document your work.

Is it Time for AC to Go Away?

You know about AC and DC, but have you heard of IAC?

Probably not, since I just made it up to describe how we are increasingly relying on wind and solar power to generate electricity. In the process, it's stored in batteries in the form of DC before passing through inverters to convert to AC and then converted back to DC again to be used by the computer chips that ultimately drive our LEDs, consoles, video projectors, and almost everything else we connect to electrical power. Each of those conversions comes with an energy cost, which is why I believe that we might one day return to a DC grid.

In the meanwhile, we'll continue to use that intermediate step using AC.

The only reason that we use AC today is because 125 years ago when Edison began building and selling DC generators, we didn't know how to change the voltage of DC, so the voltage produced by a DC generator was the voltage that had to be used by the consumer.

And when it comes to distributing electricity, there's a trade-off between safety and economy; the higher the voltage, the more dangerous but the more economical, and the lower the voltage, the safer but the more it costs to distribute. That's because of the relationship between power, voltage, and current. To transmit the same amount of power at low voltage requires bigger conductors, which cost more money.

That problem left the door wide open for George Westinghouse to walk through with his newly purchased patent on the transformer, which allowed him to build and sell AC generators. That, in turn, allowed consumers of electricity to remove their very loud and smelly generators from their property and tie into the electrical grid, which was supplied by very large generators located far from the premises, and that's mostly how it's done today.

I was reminded of this recently when I checked into my hotel in Shanghai and I found a variety of electrical connectors, including USB, which provide low-voltage DC to charge batteries in all of our devices. That's not unusual these days, but if it becomes more commonplace and expands to include higher current DC outlets, it could alleviate some issues having to do with electrical power distribution. For example, with AC, we now have to think about power factor and harmonics, which can cause overloads and overheating of electrical apparatus. Neither of those exists in the DC domain. And low-voltage DC is much safer than the 100VAC to 240VAC that we currently use around the world.

Converting to DC won't happen any time soon and there are no guarantees that it will happen at all. But imagine having universal voltage at the connection point (5VDC?), universal connectors, and universal frequency (0 Hz!). In the meanwhile, watch out for the effects of low power factor and harmonics.