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engineering

The Hazards of Being a High Voltage Engineer

The residents of Phoenix, Arizona count on a reliable source of energy to sustain their daily activities and keep cool during the hot Arizona summers. The transmission of energy from power lines to our homes is not something we worry about, but an elite team of SRP linemen does. They’re a team of 10 highly trained experts who work on live power lines transmitting up to 500,000 volts. This is their story and, hopefully it highlights some of the extreme challenged my colleagues face as high voltage engineers.

Remember, they’re trying to do this with direct physical contact from electricity running through their bodies. They call this the bare hand method and what they do, nobody else in SRP does.  They are a specialized group and they can can do anything else the journeymen lineman does at SRP, but they cannot do what we do. This method is critical in allowing linemen to work on high-voltage transmission lines without taking those lines out of service  or causing power outages.

MIKE: “We do what we do, and we try and do it in this manner to keep things in service. If we lose one of these 500 lines, you could potentially have a whole city out of power.”

Because the lines are energized,  linemen must carefully coordinate their every move while they’re still on the ground. Once their plan is in place, they put on a special, stainless steel fabric suit with flame-resistant coating. The suit protects them by causing  the electricity to flow around their bodies. Then, they climb. Once they reach the power lines, the men remain isolated within the 500,000 volt phase. That means they have to stay on the line and no further than about 11 feet from it. Outside this parameter, they risk electrocution.  In essence, they’re like birds landing on a line. By remaining away from any ground potential, they don’t complete a circuit and avoid electrocution.

ROBERT: “It feels like something’s calling all over you. If you don’t have your hood on,  it feels like your hair’s calling everywhere.  If you stick your hand out, you can feel it;  you can feel the electricity escaping. The wire has a corona around it,  and if you go outside that corona, actually, the electricity will shoot out  of your fingers, away, and they’ll hurt. At 500,000 volts, you can hear the generator  at the power plant when you have your hood on. It’s that powerful.”

The bare hand method is used  to maintain transmission lines and make a number of  different types of repairs. By having hands-on contact with the power lines,  repairs are easier and quicker.

MIKE: “With the bare hand method,  you get to go right on the wire, energize yourself to the same potential as the line and do the work right there with your hands right in front of you. So it makes things much, much easier. There’s a multitude of things that could happen. We can change a string of insulators with the line still energized, we can take care things like gunshot conductors  or damage from most anything  that would damage the conductors. You can do this and still have the line energized, so we can — with no disruption in service —  we can take care of these jobs.”

The transmission tower located  just outside of Gold Canyon is over 150 feet high. The extreme height and high voltage means every team member must maintain  a high level of concentration and there’s no room for error.

ROBERT: “We have to depend on each other.  We cannot just come in and change our patterns;  we have a set pattern on everything we do.  We have one mistake out there,  and something drastic will happen.”

The stakes are high in this line of work, and trust is critical. They rely on each other to maintain safety and get the job done. This specialized group of linemen travels together  around the Valley and beyond and can sometimes work around the clock to make critical repairs. They know each other well,  respect each other like family, and have a unique kinship.

ROBERT: “We spend 10, 12, 14 hours a day together. Sometimes we spend weeks together out of town. I spend more time with these guys  than I do with my own family.  They are my family.”

The transmission of energy  from power lines to our homes is something we can take for granted every day, and this team of commercial electricians goes through  great lengths to make sure it stays that way.

cloud computing

How To Set Up A Cloud Server Using Google Compute Engine

This is a guest post from Bruce Skinner of Pisys.net who wants to tell us how to set up a virtual server using Google’s Compute Engine – take it away Bruce.

Now that Compute Engine is open for everyone to use, I thought it’d be fun to do a demo of using Compute Engine to set up a cloud-based web server. That way you can see the process and then try it out for yourself.

Ok, let’s get started by pointing a browser to cloud.google.com/console. When you first come to the cloud console, you’ll be prompted to create a new project. We’re creating a test web server, so we’ll call it Web Server Project. Lets change the suggested project ID as well and then click Create. That will start the creation process.

Now that the project’s been created, we’ll have access to all of Google Cloud Platform’s services. Compute Engine is a paid service, so the first thing we’ll need to do is set up our billing information. You’ll be surprised at how affordable experimenting with Compute Engine can be. Next, go ahead and fill in the billing details and, after we’ve entered our billing information, we’ll navigate to the Google Compute Engine Instances page, where we’ll see a list of virtual machines that we’ve created. We don’t currently have any, so let’s add one. We’re going to create an instance called Test Web Server.

Start by clicking the New Instance button at the top of the page. Specify the name as Test Web Server. For the zone, select US Central 1B. For machine type, since this is a test, select the smallest one available, the F1 micro with one virtual CPU and just over a half a gig of RAM. And we’ll go with the suggested default image, which is Debian. Our instance is almost ready. Some final health checks are being run, which is the last step before the server is ready to use. After a few moments our instance has been created.

By default, Google Compute Engine blocks all connections to an instance from the internet. Since we want to serve web pages from our instance, we’ll need to set up a firewall to specify that incoming HTTP traffic is allowed on the network where our newly created virtual machine resides. We’ll do that by clicking Networks. Select a default network, which is where we created our virtual machine. Click the new link that appears at the top of the firewall section. Name the firewall http1. In the Protocol and Ports field, enter TCP 80. Click the Create button to complete the creation of the firewall. Once this process completes, we should see the new firewall appear in the firewalls list.

Now that the network where the virtual machine instance resides has a firewall configured to allow internet access, let’s install a web server on our virtual machine. In order to make changes like installing software on our Compute Engine virtual machine, we need to remotely access the machine. The Google Compute Engine team has created a great tool for doing this called gcutil, which is included in the Google Cloud SDK. The instructions for downloading and installing Google Cloud SDK can be found at developer.google.com/cloud/SDK. You’ll essentially download it as a file, extract it, and run an install script. Then run an authentication script and grant the tool access. I’ll go ahead and finish speeding through this process now. The authentication command here is what grants the SDK access to work with your project. An OAuth2 token is being issued and stored. We’re now set up to use gcutil. Once gcutil is installed on our machine, we can use it to remotely access the instance we created. There’s a quick way to do this if you go to the Instance Details page. On the side, there’s an SSH link. Copy the SSH command that’s provided there. Open a Terminal Window and paste the SSH command into it. You’re prompted for a pass phrase. Enter something you can remember for SSH keys. Here we are in the command line of our virtual machine instance.

Next, let’s install some software, specifically some web server software. The web server software we’re going to install is Apache. A standard command used on Linux to install software is apt-get. We’ll use that. So we’re going to type sudo to run the command as a super user, apt-get install apache2. It’s going to ask us to confirm that we want to install it. Hit y and type Enter. The installation process has started. And now Apache has been installed. As part of the installation process, Apache creates a default web page. We can try unloading that default web page in a web browser to confirm that we’re actually serving web pages. So let’s jump back to a browser to test is we can load the default web page that Apache has created. Now, to find our default page, we need to know the internet address of our server. We’ll get that on the VM Instances page of the Cloud Console. We can see our external IP address here. Open a new tab and type the IP address. And here we have the default Apache web page. Great, our test web server is serving up pages. Now to prove that this is our web server, let’s modify the default web page. We’ll start typing sudo to run the command as a super user, then nano, which is a text editor we’ll use, and then the location of the Apache default web page, which is var/www/index.html. When we run that, it opens up the index. file and the nano text editor. We’ll remove the default text that’s there. And then we’ll paste in an image, so that we can easily tell the page has been modified. We’ll save the page in nano by pressing the Command key and the X key at the same time. And then type y to save the file and close nano. Back in the browser, we should be able to Refresh the page. And there’s our new custom default web page. Now, I would call this test a success.

The final thing we need to do to wrap up our test is to delete the virtual machine and persistent disk we created. As I do that, let’s make a calculation about how much this whole test cost. So to delete the virtual machine and persistent disk, first we’ll select our test web server VM. Then scroll down and click the Delete Disk Instance button. We’ll check the option for deleting the boot disk as well. And then click OK. Our deletion process has started. The current virtual machine price for the type we use is 1.9 cents per hour. We ran our server for around 10 minutes. So our virtual machine usage cost comes in at just under a third of a cent. And there we go. The virtual machine has just been deleted. Now, back to pricing. The persistent disk pricing is $0.04 per gigabyte per month. So that roughly comes to just under half a cent for a 500 gigabyte boot disk, the default. So everything we just did on Compute Engine, we did for less than $0.01. Now, it’s your turn. Go try creating your own cloud-based web server on Compute Engine.

Business

Building a Business Website That Works

The following article is by Ian Lackie of Azzurro Blu, based in Aberdeen, Scotland,. They specialise in business management consultancy and Shrepoint development. Please take some time to visit their website for more information. Today, Ian is going to be discussing the options when it comes to developing a business class website.

Most business owners understand the value of a good business website. However, as you plan and start developing a world class business website, your process needs to be a little more involved than just finding a local web designer, and then letting them do their job. Of course, its always a good idea to hire a competent web design team but you need to give them guidance and, like most thing business you really should try and have a backup plan. Knowing what kind of content management system you would like for your business would be one way to start. In fact, you shoudl look at this even if your business already has a website.

If your current website is difficult to manage, then I recommend that you consider a free, open-source content management system likeWordPress.

Lets look at a quick example of how things pan out for businesses that get stuck with an inflexible content management system that everyone in the company finds difficult to use. Axis Bank, a major bank in India, used a CMS that was developed in-house and was deeply featured, but was almost impossible to use. When the bank needed to make a simple change – say to amend a product – in one case they  decided to withdraw a credit card that they offered – then the employees found it very complicated to actually go in and simply delete the card. Eventually, the bank’s IT staff were able to go in and make a brief note on how the product was currently withdrawn – bit it was hardly an elegant solution to a simple problem. And from a customer usability standpoint it was, shall we say, less than ideal. Wiht a vast range of cards on offer, customers had look carefully at the card they were selecting in case thery went through the application process only to discover the card had been withdrawn. Ouch!.

Difficulties of this kind are all too commonplace when using content management systems that are not designed to be user-friendly. If you really want the best business website for your needs, then you should aim for something that really easy to go in and make edits to.

Luckily, there are a number of amazing and free web publishing platforms out there that you can use to build a world class business website. There’s WordPress of course. But there is also Tumbler, Blogger, Movable Type and TypePad, among many others. In fact, with recent advances in the platform you could even consider Facebook to be a blogging platform worth considering.

Other than WordPress though, these options don’t really work well for business. They all have some limitation or another – such as being proprietary and expensive, or having limited feature sets. WordPress, on the other hand, is free, and it doesn’t hold yoou back with a a limited feature set. It can be easily used to help you build the business website that you dream of, and also the best business blog.

The WordPress platform is perfect for business for a number of reasons. The platform is very well set up for easy SEO. There’s built-in commenting, everything is easy to update, there are plug-ins by the hundred to help you achieve nearly anything you want, and you can find support all around in a very WordPress robust community.