Category: Uncategorized

No comments

Smart Meters and Their Crucial Role in the Evolution of Smart Grids

  By
Smart Meters and Their Crucial Role in the Evolution of Smart Grids

Introduction

As our world transitions toward cleaner and more sustainable energy sources, the development of smart grids becomes increasingly vital. These intelligent energy networks leverage digital technology to optimize electricity supply and demand, ensuring reliable and cost-effective power delivery. At the heart of this transformation lies a critical component: smart meters.

But how do smart meters communicate with each other and with other grid components? The communication architecture of smart grids typically relies on a combination of wired and wireless technologies, such as power line communication (PLC), radio frequency (RF), cellular networks, and internet protocols. Smart meters use these communication channels to relay data to utility control centers, where it is aggregated, analyzed, and used to optimize grid operations, predict demand, and identify potential faults or outages proactively.

In this comprehensive blog post, we delve into the multifaceted world of smart meters, exploring their role in shaping smart grids, their communication mechanisms, and the benefits and challenges they present.

The Emergence of Smart Grids

Before we dive into smart meters, let’s understand why we need a truly smart grid:

  1. Growing Energy Demand: As we electrify transportation and shift away from fossil fuels, electricity consumption is set to soar. The International Energy Agency predicts a significant rise in electricity demand over the coming years.
  2. Renewable Energy Integration: To meet this growing demand while reducing carbon emissions, there is a push to ramp up renewable energy production. However, the intermittent nature of wind and solar power poses challenges for grid management.
  3. Digitization for Optimization: Advanced technologies like sensors, machine learning algorithms, and cloud computing enable us to optimize electricity generation, distribution, and consumption. Enter the smart grid.

Smart Meters: The Cornerstone of Smart Grids

Smart meters, also called advanced meters, play a pivotal role in the transition to smart grids. Here’s why they matter:

  1. Real-Time Data: Smart meters provide detailed, real-time data on energy consumption. They replace traditional mechanical meters and allow automated transfers of information between customers and energy providers.
  2. Two-Way Communication: Smart meters enable two-way communication between consumers and utility companies. This communication ensures reliable operation, better maintenance, outage notifications, and optimal demand management.
  3. Applications and Benefits:
    • Demand-Side Management: Smart meters facilitate demand-side management, especially with the rise of electric vehicles (EVs) and new technologies like 5G/6G networks.
    • Infrastructure Sizing and Upgrade: Data-driven algorithms help plan infrastructure upgrades efficiently.
    • Generation Forecasting: Smart meters aid in predicting energy generation.
    • Privacy and Cybersecurity Challenges: Protecting user privacy and ensuring cybersecurity are critical challenges.
    • Reduce Outage Times: Utilizing data from AMI systems, utilities are better able to reduce outage times. Utilities can tie outage alerts from advanced meters to outage managements systems to respond to outages without customers even reporting an outage.

Benefits of Smart Meters

  1. Energy Efficiency: Smart meters empower consumers with real-time information, allowing them to make informed decisions about energy usage. Dynamic pricing models encourage energy-saving behaviors.
  2. Grid Optimization: Utilities gain insights into energy consumption patterns, enabling better grid management and load balancing.
  3. Integration of Renewable Energy: Smart meters facilitate the integration of intermittent renewable energy sources by providing accurate data for grid optimization.
  4. Introduce New Rates: With the information gained from AMI data, utilities can offer new rates to customers. Some customers may be able to take advantage of Time of Use rates by having access to their own data.
  5. Fault Detection and Remote Diagnostics: With the ability to detect anomalies and potential faults in the grid, smart meters enable utilities to identify and address issues promptly, minimizing downtime and improving reliability.

Challenges and Solutions

  1. Privacy and Security: Smart meters collect sensitive data. Robust privacy-preserving measures and robust cybersecurity protocols are essential.
  2. Data Transmission: Ensuring high-resolution, real-time data transmission is crucial. Improved communication infrastructure can address this challenge.
  3. Global Deployment: While smart meter adoption is surging globally, challenges persist. Collaborative efforts among countries and regulatory bodies are necessary.
  4. Cost and Infrastructure: The upfront cost of deploying smart meters and upgrading grid infrastructure can be substantial, posing financial challenges for utilities and necessitating careful planning and investment.
  5. Customer Acceptance: Despite the potential benefits, some consumers may have reservations about smart meters, citing concerns about privacy, radiation exposure, or perceived loss of control over energy usage.

Conclusion

Smart meters are not just about measuring energy; they are the linchpin connecting consumers, utilities, and the smart grid. By addressing challenges and maximizing benefits, we can unlock the full potential of smart meters and create a sustainable energy future for all.

Smart meters represent a cornerstone of the transition to smarter, more sustainable energy systems. By providing real-time visibility into energy consumption and enabling two-way communication between consumers and utilities, these devices are driving the evolution of smart grids worldwide. Despite the challenges and complexities involved, the potential benefits—enhanced grid reliability, increased energy efficiency, and greater consumer empowerment—far outweigh the obstacles. As we navigate the transition towards a more connected and resilient energy future, smart meters will continue to play a central role in shaping the grid of tomorrow.

No comments

Advanced Metering Infrastructure (AMI) and Automated Meter Reading (AMR): A Deep Dive

  By ,
Advanced Metering Infrastructure (AMI), Automated Meter Reading (AMR)

Introduction

In the realm of utility management, two technologies have revolutionized the way we monitor and control energy usage: Advanced Metering Infrastructure (AMI) and Automated Meter Reading (AMR). These systems have transformed traditional meter reading methods, paving the way for more efficient and accurate data collection.

Understanding AMI and AMR

Automated Meter Reading (AMR) is a technology that automates the process of collecting consumption data from energy metering devices. It eliminates the need for manual meter readings, reducing human error and increasing efficiency.

On the other hand, Advanced Metering Infrastructure (AMI) is a more comprehensive system. It not only automates data collection but also enables two-way communication between the meter and the central system. This allows for real-time monitoring, remote control, and a host of other advanced features.

The Technology Behind AMI and AMR

AMR systems primarily use drive-by or walk-by technologies. A utility worker with a handheld device can collect data from multiple meters without needing to access each one physically. Some AMR systems also use fixed networks for data transmission, using technologies like radio frequency (RF), power line communication (PLC), or telephony.

AMI systems, being more advanced, use a variety of communication technologies, including RF, PLC, cellular, and broadband. The choice of technology depends on factors like the utility’s requirements, the geographical area, and the existing infrastructure.

Benefits of AMI and AMR

Implementing AMI and AMR systems brings numerous benefits:

  1. Efficiency: Automated data collection reduces the time and resources required for manual meter reading.
  2. Accuracy: Automation eliminates human errors associated with manual readings.
  3. Real-time Data: AMI systems provide real-time consumption data, enabling better energy management.
  4. Customer Service: With accurate and timely data, utilities can offer improved services to customers, like detailed consumption reports and quicker response to queries.

Challenges and Real-World Applications

Despite the benefits, implementing AMI and AMR is not without challenges. These include the high initial investment, the need for skilled personnel to manage the systems, and concerns about data security and privacy.

However, many utilities worldwide have successfully implemented these systems. For instance, in Europe, AMI adoption has been driven by EU mandates requiring member states to equip 80% of consumers with smart meters by 2020. In the U.S., the 2009 Smart Grid Investment Grant program accelerated AMI deployment.

Conclusion

As we move towards a more connected and data-driven world, technologies like AMI and AMR will play a crucial role in energy management. Despite the challenges, their benefits in terms of efficiency, accuracy, and improved customer service make them a worthwhile investment for utilities worldwide. As these technologies continue to evolve, we can expect even more innovative solutions in the future.

Basic Electricity for Metering

  By

Electricity in our Lives

No single discovery has influenced our lives and existence more than electricity. We observe a huge usage of electricity in our daily life. Electricity is everywhere. It lights our homes, cooks food, runs our mobile gadgets, and plays shows on TV for us. Electricity provides air-conditioning for us to live and work in a suitable environment. It provides massive assistance in medical and medicine field, saving thousands of life and making our life more livable and better. It would not be possible to communicate with each other from such long distances without electricity. People now can read books and online articles on a computer sitting at home instead of physically going to libraries. Electricity has made our daily routine more efficient and productive.

Basic Principles of Electricity

Electricity is basically a flow of electrons in a circuit in the presence of some potential difference across a circuit. Electricity reaches our homes in the United States generally with three wires. One wire of either black or red color is called live or hot wire, while the other wire of either white or grey color is called neutral wire. Finally, there is a green or bare wire called the ground wire. The live, or hot, wire has a certain potential with respect to neutral wire and it provides electric current to all appliances, while the neutral wire collects all current back to grid. There is another wire in our home circuitry called ground wire which helps protect us from electric shock.

Faraday’s Law

Electricity is produced on the Faraday’s Law of electromagnetic induction. This principle says that if a closed circuit loop/coil moves back and forth, or rotates in a magnetic field, then electricity is generated in that circuit. Electric generators use this principle to produce electricity.

Current, Voltage, and Resistance

Electricity is mainly characterized by three basic electrical quantities which are current, voltage and resistance. The current is composed of the flow of electrons through a particular point in the circuit. It is defined as: “the number of electrons passing through any particular cross section of wire in one second”. It is measured in amperes (A) and is represented by following formula:

I=dQ/dt

  Where Q is electrons, and t is time.

The voltage, or potential difference, is basically the driving force if electrons in a closed circuit. Voltage is measured in volts. It is usually denoted by V and represented by following formula:

V=dW/dQ

  Where W is work done, and Q represents the charge in coulombs

The third electrical quantity is resistance (R) which is defined as: “the measure of opposition to the flow of current in a circuit”. It basically limits the current flow in a circuit. It is measured in ohms (Ω). Resistance of a material is related to its physical properties. Based on the resistance, there are three types of material, which are:

  1. Conductors which pass electric current easily
  2. Semi-conductors which allow to flow current under certain conditions
  3. Insulators which do not allow current to flow through them

You can visualize how an electric circuit works based on a filled water tank with a hole at the bottom of it. The water represents the amount of current which is coming out that hole. This water flow is limited by the dimensions of the hole which represents resistance. While the speed of water coming out depends upon height of water level which represents the voltage level.

The current, voltage and resistance are related to each other by Ohm’s law. This law states: “the electric current in a circuit is directly proportional to the applied voltage” and is represented by following equation:

V=I*R

  Where V is voltage, I is current and R is resistance.

Direct Current and Alternating Current

There are two types of current or electricity. One is AC which is Alternating Current and other is DC which is Direct Current. Alternating current is defined as: “the current which changes its magnitude and direction with respect to time in a circuit” while direct current is defined as “the current whose magnitude and direction remains constant with respect to time”. Electric generators produce AC current based on Faraday’s electromagnetic induction principle, while batteries or cells produce DC current based on chemical reactions inside them.

The electricity that utility companies provide to their consumers is generally AC. Electricity has voltage level of 120V and frequency 60Hz in United States, while it is normally 220V and 50Hz in most European countries. However industries and factories may utilize three phases AC electricity because of their heavy loads.

Watts

Power, measured in watts, comes from multiplying the voltage times the current in a circuit. For example, a ceiling fan has load of around 100W, while iron has around 1000W as well. The electric energy for billing is measured in kilowatt hour (kWh) units. Kilowatt hours are recorded by the electric energy meters installed outside most homes and businesses. Kilowatt hours (kWh) are equal to the number of watts an appliance is rated for times the number of hours of usage for that appliance. If a 1000W load runs for 1 hour, it will be equal to 1kWh. The electricity bill of a consumer is calculated based on the number of kilowatt hours a customer uses in a month.

Why Does it Seem Like my Power Bill Keeps Going Up?

  By

Your power bill can be one of the largest variable costs that your family pays each and every month. Because of that, it can be an emotional thing when the bill is higher than normal, or if it continues to climb higher and higher. What I want to show you today are a few simple and free steps that you can take to start troubleshooting you high power bill and get you on the path to lowering that energy bill.

Step 1

The first step to figuring out why you power bill keeps going up is to look at your past billing statements. Not just the one from last month, but preferably the one from the same month last year. You need to look at the number of kilowatt hours (kWh), that you were billed for last year in the same month. If there is a large difference you may have a problem. If the difference is close then that just means that you are using about the same amount of energy this year that you did at this time last year. This is your average.

Step 2

If you have determined that you are using much more electricity this year than you were last year the first thing that you need to consider is your heating and cooling system. The heating and cooling system is by far the largest consumer of energy in the home. Sometimes you already know that you are having a problem but you just do not want to admit it to yourself. Maybe the house is just not getting warm enough or cool enough. Sometimes we like to compensate by adding space heaters or window units. While these things work great to keep us comfortable, they can really increase your power bill.

Step 3

Once you have decided that, or ruled out, your heating and air system are the culprit of you high bill, it is time to start troubleshooting. Knowing how to read your meter will be helpful as well as knowing how to do a watt load check. These will help you determine what is pulling all of the load in your home. To find out what is making your bill so high you will need a partner. This partner will either go stand in front of the meter or will turn things off at the breaker panel for you. Note, only turn things off in the panel if everything looks safe and you feel safe doing it. There are many old panels out there that are falling apart these days. Approach at your own risk. Also know that turning breakers on and off has been known to break them requiring replacement, so be careful.

When you turn off a breaker, if there is a load that is being fed by that breaker, it will turn off. When it does, the meter will slow down or stop. So, you want to continue turning off your breakers one at a time until you find the one that turns off a large load. This could be your culprit. Sometimes it is tough to track down. Many times you will think that there is nothing on yet the meter is still spinning. Turn the breakers off until you find it and then go around the house and find out what is off. That is what is using the energy.

Step 4

Once have everything tracked down you need to calculate your bill. Doing this will help you understand your energy usage and will help you save on your next bill!

How to Calculate the Full Load Ampacity of a Transformer

  By







Knowing how to calculate the full load ampacity of a transformer is a very important calculation to have in your bag of tricks as a meter technician. Here I want to show you how to do the calculation as well as provide why you want to calculate the full load ampacity of a transformer. Finally, I will show you how you can use the calculation to troubleshoot a transformer-rated metering installation.

How to calculate the full load ampacity of a Transformer

There a couple of things that you need to know before you start to calculate the full load ampacity of the transformer in question. First, what are you even calculating? You need to know what your answer represents before you go punching numbers into your calculator. The full load ampacity describes how many amps the transformer is designed to handle. This is important because it helps determine what size transformer is needed to handle a particular load.

Many times we receive information about load in terms of amps. Well, most transformers are sized based on KVA, kilovolt-amperes. Since transformer are sized based on KVA we need to convert this number to amps in order to know what the transformer is capable of handling.

Next we need to know a couple of other things. One is the line to line voltage of the secondary output of the transformer. You also need to know if the transformer is a single phase transformer or a three phase transformer. Once you know all of this information you can start with the calculation. For simplicity we will start with 100 KVA single phase 240v transformer. To calculate the full load ampacity use the following formula:

KVA x 1000

Line to Line voltage

So, for a 100 KVA transformer we will multiply 100 x 1000 and then divide it by 240v.

100 x 1000

240v

That gives us 416.67 amps. So, for a 100 KVA 240v single phase transformer the full load ampacity is 416.67 amps.

Next let’s calculate the full load ampacity of a three phase transformer. There is one more step that you have to do in order to find the full load ampacity and that is to use the square root of 3 which rounds out to around 1.732. Let’s do the same thing for a 120/208v three phase transformer. Use the following formula:

KVA x 1000

Line to Line voltage x 1.732

For a 120/208v three phase 100 KVA tranformer we calculate the full load ampacity as follows:

100 x 1000

208 x 1.732

That gives us 277.58 amps. So, for a 100 KVA 120/208v three phase transformer the full load ampacity is 277.58 amps.







Why Calculate the full load Ampacity?

Now that you know how to calculate the full load amps of a transformer you probably are wondering why in the world you did that in the first place.

One reason specific to metering is that it tells you the number of amps a transformer is capable of producing so you can size your CT’s accordingly. In both examples above you can get away with using 200:5 CT’s with a rating factor of at least 3. This covers the entire operating range of each transformer.

Another reason to know the full load amps is that it ensures that you are not over or undersizing your transformer. An undersized transformer is one that is going to have a shorter life span because of the excess heat that is generated due to being overloaded. An oversized transformer is a transformer that is being under utilized. This adds up in the form of increased system losses because even though the tranformer has plenty of capacity the coils still have to be energized and this can be thought of as waste.

Troubleshooting

Knowing how to calculate the full load ampacity of a transformer can help you troubleshoot the entire installation. You as the meter tech will most likely be going out and testing transformer-rated metering installations. Many of these will be installed on tranformers that are serving only one customer. When you test the site you will find out how many amps are on the service. You can then take this information and compare it to the full load capacity of the transfomer.

Another thing that you will do is look at the demand on a transfomer by looking at all of the meters being served by a particular transformer. Looking at each meter individually will only let you know what each service is pulling on its own. If you add each of these service together you will be able to tell whether or not the transformer is sized properly.

Conclusion

Finding the full load ampacity of a transformer is a very useful calculation to have on hand. It can alert you to problems that may arise on your system as well as help you install the right size CT’s.







Hot Sockets in Meter Bases

  By









Hot sockets are one of the things hot socketthat you will encounter if you spend anytime working in self-contained meter bases or changing meters. Here I want to discuss a few things that cause hot sockets, what kind of damage a hot socket can cause and what to look for when changing meters to spot a hot socket.

What causes Hot Sockets?

The biggest cause of hot sockets seems to be in my experience, loose connections. Loose connections can be at a couple of different places in the meter base. One of the places is where the wire attaches to the lugs. This is a notorious spot that heats up over time when it is not tightened properly. What happens is over time little micro arcs occur between the loose wire and the lug causing it to overheat. This, in turn, causes the socket terminal where the meter plugs in to overheat and voila, you have your first cause of a hot socket.

Another cause is the terminal or socket itself. In most meter bases these are spring loaded jaws that apply force to the terminals on the back of the meter. When the meter is pulled and set these jaws open and close back. Sometimes plastic boots are installed on the terminals of the meter in order to turn off a customer for non-payment or for any other reason. The more a meter is pulled in and out of these jaws the looser they become. When they get slack then tiny micro arcs happen which causes the terminal to overheat and we have another cause of a hot socket.

Yet another cause is the hot and the cold along with fluctuations in the load. As the metal in the terminals heats up and cools down due to the weather and load changes it expands and contracts. This over time can cause the jaws to loosen up and overheat.

A hot socket can also be caused where the terminal is put together or attaches to the bus bar in the meter base. Sometimes it is a screw or bolt and other times it is springloaded jaws that connect to bus bar. Either way, any slackness and you will eventually end up with a hot socket.

What kind of damage can a Hot Socket cause?

A hot socket is a very dangerous occurence. The worst thing it could cause is a house fire. You can see in the picures below that a hot socket in a meter base can lead to melted wire. It can also lead to overheated terminals on the meter itself. This causes irreversible damage to the meter to the point that the meter has to be replaced.

hot socket

Especially with the newer solid state meters there seems to be a lower tolerance for overheating of the terminals in a meter base. It is also not uncommon for customers who have hot sockets to experience flickering and dimming lights.

What to look for when changing meters?

When changing meters it is imperative that before pulling out any meter a quick visual inspection is done. This includes looking at the front of the meter and visually inspecting the wiring and terminals before pulling the meter out. It is very important not to take this step for granted. When terminals get so hot that they fail they can actually weld the terminals to the socket. This along with melted blocks in the meter base can cause a serious safety issue when pulling the meter.









So, look at the back of the meter the best you can before pulling it out. Once the meter is out you need to visually inspect the meter and the meter base before installing a new one. Some of the signs of an overheated terminal on a meter are discoloration and melting of the base plate. Likewise, some of the signs of a hot socket are discoloration and melted blocks and wire.

If you find this situation do not put a meter back in. The blocks, and possibly the wire and meter will all need to be replaced. Depending on you jurisdiction, this may be up to the utility or the homeowner to repair.

Conclusion

Hot sockets are something that every utility deals with. Be sure to be on the lookout for the causes and effects of hot sockets to keep those meters turning. As always, like us on Facebook and invite your friends!







Edison and the Electric Chair: A Story of Light and Death A Review

  By








Recently I read Edison and the Electric Chair: A Story of Light and Death. I wanted to give a quick review of the book in case anyone was thinking about reading it.

Review

When I picked this book to read I thought that it would be more about the electric chair. Not that I am totally interested in the electric chair or the death penalty or anything. Also, I did not know that Thomas Edison had anything to do with the electric chair.

It turns out though that this book does not focus a ton on the electric chair. It does do a decent job offering a bit of biographical information on Thomas Edison. I feel like the book focused more on the battle between alternating current and direct current.

Obviously Thomas Edison was a proponent of his own direct current system over the alternating current of George Westinghouse. So, the book focused more on the war between George Westinghouse and Thomas Edison than it did on the electric chair. Which, in my opinion was not a bad thing.

The book talks about the discovery of the light bulb and how it changed the world. It also talks about how different electric companies started.

How does it relate to Metering?

There are actually a couple of mentions of meters in this book. One is from one of the metering pioneers Elihu Thompson.

What about Thomas Edison and the Electric Chair?

There is a good discussion of the electric chair and how it was chosen to become the new humane way of enforcing the death penalty. Several examples of different methods are described and there are pictures included as well. I am not going to spoil the book but it also talks much about Thomas Edison’s role.

Would I Recommend Edison and the Electric Chair: A Story of Light and Death?

The answer is yes. Overall I thought that it was a good book and I would recommend it. I was able to learn something and anytime you can learn something it is usually a good thing. If you are interested in checking this book out follow the link for Edison and the Electric Chair: A Story of Light and Death.









What is the difference between voltage and current?

  By








Voltage and current are two different measures that are found in electricity. They are both present in every electrical circuit from the flashlight all the way to refrigerators. But, the question is what is the difference? To illustrate the difference between voltage and current we will look at the age old comparison of electricity to water.

Current Flow

Current is a bit easier to illustrate. We can compare it to water in a garden hose. Imagine you have a simple water wheel. To make this water wheel turn you need to pour water over it. Let’s say we have two different sized water hoses. One is 3/4″ and the other is 1″. Now, let’s pour the water over the water wheel with the smaller hose and see what happens. The water wheel turns. Now, the larger hose. What happens? The water wheel turns faster.

This is a result of more water flowing in the larger water hose. More water = faster water wheel. Pretty simple. We need to make sure that when we think of current in the same way as water in a hose that we always think of the hose as full all the time. That way when you turn the hose on you instantly have water flow.

In the early days of electricity it was a commonly held belief that electricity was a fluid. This fluid was made up of tiny particles that would flow into different materials.

Voltage, the Driving Force

Again we are going to compare voltage to the water system. First remember that voltage is the driving or electromotive force that is a part of electrical circuits. How does this translate to water? Think of the voltage as the pressure in a water system.








With the two hoses from the example above how can we make the smaller hose move the water wheel faster? With more pressure of course. So, with more pressure the smaller hose can make the water wheel turn faster. How does this relate to voltage?

Example

Look at the distribution lines above your head next time you are out and about. The wires on these lines carry thousands of volts. However, they are not very big. Remember Ohm’s Law? Let’s say you have a 2,500 watt motor. This is a multi-voltage motor. Meaning that you can wire it a couple of different ways depending on the voltage available. You need to run new wires to this motor, but what size do you need? That depends on the voltage.

Wait, I know what you are saying. Wire is sized by the number of amps. You are correct. However, depending on the voltage we may be able to run a smaller wire therefore possibly saving money. If the voltage in this case is 120 then the amperage will be 2,500/120 = 20.8 amps requiring a 10 gauge wire. If the voltage is 240 then the amperage will be 2,500/240 = 10.4 amps requiring a smaller 12 gauge wire.

Conclusion

Voltage and current are two different quantities that go hand in hand. Voltage is the driving force while current is the flow of electrons in the circuit.









What is Electric Current and how it relates to Metering

  By








What is electric current? A good question indeed. What is the unit of measure for electric current? How can we measure electric current? And finally how does it relate to metering? These are the questions that will be tackled in this post. So, let’s get started with the first one.

What is electric current?

Electric current is the flow of electrons in a circuit. It is also what is used to power our stuff. Remember that in a circuit we have both voltage and current available. But, without the current flow our electrical stuff does not move. So, now that you know that electric current is the flow of electrons in a circuit what is the unit of measure used?

What is the unit of measure?

Current is measured using what are known as amperes, or amps for short. This is typically notated as an “A” in formulas but can also be notated as an “I”. This “I” stands for intensity of current. As with any unit of measure amps can be smaller or larger. So, it is not uncommon to see milliamps or kiloamps. Milliamps is typically notated as mA and kiloamps as kA. So, now that you know the unit of measure, how do you measure amps?

How do you measure Amps?

Amps, or electric current, are measured using what is known as an ammeter. An ammeter can come in a couple of different varieties. There is the common clamp on ammeter. The clamp on ammeter comes with a spring loaded jaw that enables you to open the jaw and place it around the conductors. This places the ammeter in parallel with the circuit. Clamp on ammeters can be found in digital and analog variants.

Another type of ammeter is placed in series with the circuit. These are typically found on multimeters. Also, when an ammeter is placed in series in the circuit it typically is not able to measure a very substantial load. Make sure you read the specs on your meter before you place it in series in any circuit.







How does electric current relate to Metering?

Ah yes, finally, the meat of the article. Electric current is very important to metering. This is because we are essentially measuring the changes in current flow. Remember that using Ohm’s law and the power formula that Watts = Volts x Amps. This means that the amount of watts used are in direct proportion to the amount of current that is being used. As the amps go up, so does the watts. As the amps go down so do the watts.

We as meter techs should know how amps relates to watts and how to convert amps to watts. We should also know how to go the other way and convert watts to amps. This will help us in troubleshooting with customers. Let’s have an example.

A customer is complaining of a high bill. You go to the meter and notice it is spinning pretty fast. So, you take the cover off the meter base and check the amperage. Let’s say that it is 30 amps. How do you convert this 30 amps to watts? Using Ohm’s law we plug in the numbers. Assume this is a 240v service. W = 240 volts x 30 amps = 7,200 watts. Let’s convert that to kilowatts and divide 7,200 by 1,000. We get 7.2 kw. This means that whatever the customer has on is pulling 7.2 kw and if left on for one hour it will use 7.2 kwh. A load like this could mean that an appliance like the air conditioning is not functioning properly and is running all day.

Conclusion

Electric current is one of the most important units we have in metering. It is measured by using ammeters and its unit of measurement is the amp. Using Ohm’s law we can convert amps to watts and back again.








What is Voltage and how it relates to Metering

  By








What is voltage? This is certainly an important term to know in the electrical field. You hear it all the time. What is the voltage on the machine? Or, can you check the voltage on that circuit? We hear it, we say it but, what is voltage and how does it relate to metering?

What is voltage?

The most commonly used voltage definition states that voltage is the difference in potential between two points in a circuit. What a definition of voltage right? Another way that voltage is defined is by talking about water. Some find it easier to understand the voltage definition when we talk in terms of water pipes. Voltage is the driving force in an electrical circuit. We can think of it as the pressure in the circuit. So, what is voltage? It is the driving force in an electrical circuit.

How is voltage measured?

Voltage is measured using a voltmeter. With a voltmeter we can choose two different points in the circuit to measure the difference in potential across those two points. The unit of measure for voltage is known as the volt. The volt is named after Alessandro Volta who created the first battery known as a voltaic pile.

How does voltage relate to metering?

Ah yes, the big question is, how do we use voltage in metering? Well, we have to remember that meters measure kilowatts. So, what does that have to do with voltage? To find the kilowatts, we first need to find the watts. To calculate watts we need to know the current and the, you guessed it, voltage. Using Ohm’s Law we know that power is equal to voltage times current or stated mathematically, P = I x E. There are several ways you can remember this formula. One is by remembering the word PIE. Another is to change the letters to W = V x A.








In the first example, P = power measured in watts, I = current measured in amps, and E = voltage measured in volts. Just a quick fact here, E is the letter used because it stands for electromotive force which is a fancy way to say voltage.

In the second example, W = watts, V = voltage, A = amps. So, the two equations are equal they are just using different terms. The easy way to remember W = V x A is to think of West Virginia or W VA. Pretty simple right.

So, now that we know the terms we need to know how they relate to metering. Well, the nominal voltage in a typical metering circuit remains pretty much constant. A common household voltage is 120/240. So, the meter measures this voltage and then multiplies the voltage times the current in the circuit to get watts. And then as if by magic the readout is in kilowatts.

What?

Look at the equations again and go back to algebra I. If the voltage stays constant and the amperage goes up that means that the wattage will go up. If the amperage goes down, the wattage goes down. To get kilowatts from watts, divide the watts by 1000. In the older electromechanical meters the voltage coil, also known as potential coil, produced a magnetic field in the meter. When current flows through the meter it produces a magnetic field as well. The interaction between these two fields are what causes the disc to turn. So this is why it is important to make sure that the meter chosen for each installation is crucial.

Conclusion

Voltage is the driving force behind each and every electrical circuit. We can use Ohm’s law to calculate watts using the power formula. It is the interaction of voltage and current in a circuit that causes the meter disc to spin. To check the voltage in a circuit we use what is called a voltmeter.









Truper Automatic Wire Stripper Review

  By








An automatic wire stripper can really add to your arsenal of electric tools. The ability to quickly, easily and cleanly strip wire can increase your productivity and reduce waste. Until the automatic wire stripper came about, you really had two options. You could use your knife to strip wire, or you could use a regular wire stripper like the Klein Tools 11047 Wire Stripper/Cutter. What I want to do is give my review of the Truper Automatic Wire Stripper.

Using a knife to strip wire works but there is always the risk of cutting yourself in the process. There is also the risk that you may nick the wire and degrade its capacity. You can also use the standard wire strippers. They work well but there is some skill involved with those as well. You need to know your strippers to know which slots correlate to which size wire. There is also a risk of cutting into the wire as well.

Truper Automatic Wire Stripper

truper automatic wire stripperThese wire strippers can be used to skin wire from 22 AWG – 10 AWG. This gives you a very wide range of wire sizes to choose from. And the best thing about them is that they are automatic. This means that you will not need to squint really hard to see which hold in your regular wire strippers you need to use. You just lay the wire in there and squeeze. That’s it!

I have used normal wire strippers for most of my career. I have also used a knife to skin wire for most of my career as well. So, when I bought these automatic wire strippers I was a bit skeptical. But, they really do a great job of stripping the wire.

Details

truper automatic wire stripper jawsThe Truper automatic wire stripper features a guide that can be set up so all of your strips are the same length. This can be very useful for really anything you are doing. If you are making up a panel and you want all of your strips to be the same length so that just the right amount of bare wire is under the connector, you can do that. All you have to do is move it until you get the right length. Then set it and forget it. It really is that easy.

These automatic strippers also feature a wire cutter. However, it is not the best. It is located between the handles so you do not get a ton of leverage. When I was using them there were a few times where it did not cut all the strands of the stranded wire I was working with. But, these are not really made for cutting wire, they are made for stripping wire. If you are looking to cut wire then check out my review of the Truper Lineman’s Pliers.








Another feature of the this automatic wire stripper is the ability to crimp wire. It offers three different positions for crimping. Again, these are in the middle of the handles. I have never had good luck with any strippers or wire crimpers where the stripping, cutting or crimping is in between the handles.

The grips on these automatic wire strippers are comfortable. They offer plenty of leverage to carry out fast and precise wire strips.

Conclusion

The Truper Automatic Wire Stripper is a tool I wish that I would have had many years ago when I started in the meter field. I think about all of those meter bases I have wired up through the years where I used my knife or regular wire strippers to skin the wire. All of those CT’s and PT’s that I have wired up through the years could have been done much faster.

I highly recommend this tool. After using this tool on the first job you will not regret buying it. It makes stripping wire practically effortless.









Truper Heavy Duty Lineman’s Pliers Review

  By








Lineman’s pliers are one of the most important hand tools in a meter tech’s arsenal of tools. A good set of lineman’s pliers allows you to cut and bend wire with ease. They also need to be durable enough to be used at times as a hammer. Now, trust me I know that they are not a hammer but can you honestly tell me that you have never used your pliers to beat on something? One of the things that meter techs use lineman’s pliers for is cutting meter seals. Most of these types of meter seals have a steel wire which is harder than copper. This means that the pliers must be up to the task of cutting the steel day in and day out.

Now, I know that the Klein Tools 9-Inch High Leverage Side Cutting Pliers are pretty much the standard in the electrical field. But what if you need a set of pliers that work just as well but are different than everyone else? Are there any options out there?

Truper Heavy Duty Lineman’s Pliers

Truper Heavy Duty Lineman's Pliers

Truper is not a new company but it is not as well known in the electrical field as names like Klein, Greenlee and Ideal. But, they do make a good set of lineman’s pliers. Their 9″ heavy duty pliers are made of forged chrome vanadium steel which is supposed to be two times stronger than carbon steel. They also feature a good comfortable grips. The finish on the pliers is a satin finish which helps with rust resistance.







My Review

Truper Heavy Duy Pliers LengthSo, what do I think about the Truper Heavy Duty Lineman’s Pliers? All in all I think that they are a good tool for any toolbox out there. I do not think that you would be disappointed if you made the purchase. Now, there are a couple of things that I would like to mention about these pliers. The overall length is about 9.5″. The distance from the pivot point to the end of the handle is about 7.5″. This means that you get good leverage when using these pliers.

The grips are comfortable and they offer a raised portion to help aid in holding on to the pliers. I also feel like this helps keep your hands from slipping if you need to use the pliers to push something as well. I also want to note that the grips are not for use on live circuits. So, keep that in mind when using these pliers. I have used Klein Pliers most of my career and one difference that I notice between these and the Klein are that the head of Truper pliers seems to be larger. That could be a good thing if you are using the pliers to bang on things because of the added mass. It could also be bad if you need to get into tight spaces.

My biggest complaint with the pliers is the jaw design. You can see in the picture below what I am talking about. Just below the cutters there is a gap when the jaw open. More than once while using these pliers to cut wire the wire has fallen into that gap. This prevents you from cutting the wire because the gap portion clamps down on wire. Once you get used to it, there is no problem. Just something I though I would point out.Truper heavy duty lineman's pliers jaw

Conclusion

Would I buy the Truper Heavy Duty Lineman’s Pliers? The answer is yes. Although they are not perfect they are perfectly capable of handling any task with ease. Whether it be cutting, bending, pulling wire or wiring up CT’s these pliers get the job done.









Increasing Revenue with High Accuracy CT’s

  By








Increasing revenue is something that we all want to do. High accuracy CT’s can help us achieve that goal. When it comes to instrument rated metering installations we have to remember that our meter is only as accurate as our CT’s. So, the first step in making sure we are accurately measuring our metering installations is making sure we have the most accurate CT’s installed.

Standard Vs. High Accuracy

This is where high accuracy CT’s come into play. Remember that standard current transformers are only guaranteed accurate to within 0.3% from the nameplate value to the rating factor. Also, standard CT’s are 0.6% accurate from 10% of the nameplate value up to the nameplate value. This means that for a common 600:5 CT that anything below 60 amps is not guaranteed to be measured accurately. So, what do you do?

You install a high accuracy CT that is 0.15% accurate from 5% of its nameplate rating through the rating factor. Now, using the same 600:5 ratio as an example, we are now able to measure down to 30 amps with 0.15% accuracy. This is high accuracy CT’s are used to help with increasing revenue.

Where can high accuracy CT’s help with increasing revenue?

One of the places where high accuracy CT’s can help with increasing revenues are department stores or industrial factories that have been converted to warehouse space. These types of customer changes can cause revenue losses because the infrastructure that was put in for these larger customers who have now left or have converted their spaces is no longer being utilized.








Let’s say that the customer was doing some small scale manufacturing and decided that the space was no longer big enough for its manufacturing needs. So, they decide to move into a larger space and convert this previous space into warehousing. Let’s keep with the standard 600:5 for this example. For this example let’s also assume that the rating factor of this standard CT was three. We are also going to assume that we were using this rating factor. Meaning that this was a 1200 amp service and we installed 600:5 CT’s with a rating factor of 3, to make sure that the CT’s were as saturated as possible.

The customer in this example typically pulls around 750-800 amps. This is well within the range of our standard accuracy 600:5 CT’s. Now when they leave, they take all of the manufacturing equipment with them and only leave a few lights. There new load is now only around 40 amps. They do not need to heat or cool the space because what they are storing does not require it. So now, the standard 600:5 CT is not guaranteed to measure the 40 amps accurately.

What if we had installed a high accuracy CT?

If we had installed a high accuracy CT to begin with then we would not be worried. The high accuracy 600:5 CT is able to measure down to 30 amps with 0.15% accuracy. This means we capture those 40 amps and we do so accurately. This is how high accuracy CT’s play a vital role in increasing revenue.

Conclusion

In conclusion, if you are concerned with increasing revenue make sure that you are giving a look to high accuracy CT’s. They can be placed anywhere your standard accuracy CT’s are and can instantly start increasing revenue. High accuracy CT’s help mitigate low current situations such as when large customers move out or convert. If you are in the market for high accuracy CT’s check out Peak Demand.









Tagged   

Reducing Inventory with High Accuracy CTs

  By








Reducing inventory is a big concern with utilities these days. This is primarily driven by the fact that reducing inventory means reduced costs. Reducing costs means that the profit margin can be higher. So, what does that have to do with high accuracy CT’s? How can high accuracy CT’s reduce inventory?

Use the Extended Range of High Accuracy CT’s

When placing new CT’s in service we traditionally had a variety of different CT ratios to choose from. Among the most popular are 200:5, 400:5 and 600:5 variants. This means that when a new service is built the meter tech or engineer will look at the service and size the CT’s according to the projected load. This is done because we want the amps on the service as close to the nameplate rating as possible. We do this because standard CT’s are most accurate at their nameplate rating up to their rating factor.

So, if we have a 400 amp service that is projected to normally run around half of that or less we may use 200:5 CT’s with a rating factor of at least two. This ensures that when the amperage is low we can measure it as accurately as possible.

Enter the new kid on the block. The high accuracy CT. With the high accuracy CT, with its extended range features we can now use one size CT for most of our installations. For instance a 600:5 high accuracy CT will allow us to measure down to 30 amps. But there is more. Many manufacturers are offering these high accuracy CT’s with extended ranges that can measure down even further.



How can High Accuracy CT’s be useful in Reducing Inventory?

High accuracy CT’s can reduce inventory by reducing the number of different ratios that you need. You can now purchase a 600:5 CT with a rating factor of 2 or more that can cover all your needs. This means that you no longer need to use 200:5 or 400:5 CT’s. You can stock one size. This allows you to purchase less. Even if you do not have a new job coming up, in the past you would have needed to keep a certain number of 200:5 and 400:5 CT’s on the shelf for emergencies.

So, instead of having a couple of sets of each size, you can have just a couple of sets of 600:5 CT’s that can be used for each service type. Instead of having purchased four sets of CT’s now you have only purchased two. This is beneficial to reducing inventory and cutting costs. Also, it leads to a reduction in storage space as well.

Conclusion

High accuracy CT’s can be a great way of reducing inventory in your meter shop or warehouse. Look at what you have stored in your warehouse and see if you could benefit from reducing the number of CT’s that are just sitting on the shelf as spares. If you are interested in high accuracy CT’s check out the offerings from Peak Demand.









Tagged   

Extended Range CTs VS High Accuracy CTs

  By








Extended range CT’s are all the rage with CT sales people now. But what exactly are they? Don’t we already have high accuracy CT options out there? Is there a difference in extended range CTs and high accuracy CTs? I will try and break these terms down and explain what the difference is between extended range CTs and high accuracy CTs.

What are Extended Range CTs?

To understand what extended range CTs are we need to understand what standard range CTs are. Standard range CTs have a measurement range from 0 amps through their rating factor. However, notice that I said measurement and not accuracy. That is because if we remember correctly that standard CTs are only certified as being accurate to 0.6% from 10% of their nameplate rating through the nameplate rating. Furthermore, at the nameplate rating up through the rating factor they are accurate to within 0.3%.

So, obviously an extended range CT would be better than that right? Well, yes. However, there is a caveat. That being that there is no standard when it comes to the term “extended range CT.” These extended ranges are noted in the literature that comes from the manufacturer of the CT. This means that the CT could be accurate down to 3% of the nameplate value or even down to 1%. This however all depends on the manufacturer. Which leads us to our next point.

Don’t we Already Have High Accuracy CTs?

The answer to that question is yes. But let’s remember that to be classified as a high accuracy CT that there are certain guidelines that must be adhered to. The IEEE is the body that defines that standard. If you want to learn more about high accuracy CTs follow the link. So the next question then is why do we have extended range CTs if high accuracy CTs already exist and is there a difference?



What is the difference between extended range CTs and high accuracy CTs?

The first difference is that high accuracy CTs actually have a standard that must be met to be called high accuracy. Extended range CTs however do not have this standard. However, most extended range CTs are high accuracy CTs. The reason for this is because manufacturers need a way to separate themselves from the competition. It is not good enough for them to just meet the standard. They need to go above and beyond the standard to attract more customers.

This is good for utilities because it means that in the end they have access to more choices and better products. Utilities who want high accuracy CTs will find that not only are they available but they are available with more extended ranges than the standard requires. Just remember also that an extended range CT is not always high accuracy. Check and make sure that the CT has a rating for high accuracy before believing the salesman. Extended range is something that the manufacturer decides.

Conclusion

Extended range CTs can be used anywhere standard CTs are used. They allow you the ability to meter lower levels of current than you would have before now. This also permits greater revenue over the life of the CT. However, make sure that the CT is high accuracy before you jump on the extended range bandwagon.









Tagged