Programmable AC sources are evolving as their performance increases, and they add features. If you are in the market for an AC source for the first time in five or ten years, you will notice some significant differences.
If you are in the market for a programmable DC power supply for the first time in five or ten years, you will notice some significant improvements. Modern supplies offer higher power densities, helping you save rack space. In addition, modern supplies can provide considerable flexibility in power, current, and voltage ratings, helping you future-proof your test systems to meet changing requirements.
Legacy Products EOL Announcement Offers Extensive Transition Period
Renewable energy continues gaining momentum. Of the 2.7% increase in U.S. electricity sales in 2022, nearly all of it came from solar and wind sources, according to the U.S. Energy Information Administration (EIA). The organization estimates that renewable sources provided 22% of U.S. generation in 2022 and will provide 24% in 2023.1
When choosing programmable AC sources and DC supplies, look beyond the headline specs, such as power and voltage, before purchasing. Choose a vendor who offers flexibility concerning interface options, software support, size and weight, output measurement capabilities, and environmental conditions.
Actuators that operate aircraft flight-control surfaces undergo extensive ground tests before they take to the sky. The electrohydrostatic actuators (EHAs) used on the F-35 joint strike fighter serve as examples that illustrate the test challenges involved.
Programmable AC power sources seem like straightforward components that you can integrate into a test system, but make sure not to overlook critical details before issuing a purchase order.
The James Webb Space Telescope (JWST) is in the news as it fends off micrometeoroids and begins transmitting full-color images and spectroscopic data. But JWST is just one of many spacecraft that launch annually using AMETEK Programmable Power Elgar Solar array simulators. Fortune Business Insights sees a bright future for the industry, with the market for medium and large satellites expected to grow at a CAGR of 4.20% to reach $14.98 billion in 2028.
AMETEK Programmable Power is always committed to fostering a positive, welcoming, and encouraging work environment for all employees. We are especially proud and have enjoyed a few events that have been organized in the first half of 2022. Continue reading to get a taste of our events this year so far.
According to U.S. Department of Energy, wind power is rapidly proliferating with wind installations outpacing solar installations in the United States. The DoE projects that U.S.-based onshore and offshore installations will more than triple and reach 404.25 GW across 48 states in 2050. Each wind turbine that rolls out in the coming years to help meet this projection will require extensive testing.
Multiple-output programmable DC power supplies can serve a wide range of applications, extending from semiconductor tests to process control. When selecting such supplies, look for flexibility as well as power density. Concerning the latter, choose a supply that maximizes output power while minimizing size—for example, a three-output supply that offers a 5,100W total output power in a 1U chassis.
When choosing programmable DC power supplies, you have many options. You can choose from a wide range of voltage, current, and power ratings. You will also select other specifications, including input voltage, output voltage regulation, output ripple and noise, and transient response time to a step input. Then, you will want to consider digital communications options, software compatibility, and whether you will need manual front-panel controls. And of course, you will also have multiple vendors from which to choose.
Automated test systems for aerospace/defense programs require instruments, programmable power supplies and loads, and high-density switching systems designed for reliability, performance, and flexibility. AMETEK Programmable Power and AMETEK VTI Instruments stand ready to assist the aerospace/defense community in implementing its core testing strategy. Previously, the industry had deployed a dedicated test station for each device under test (DUT). In contrast, the core testing strategy deploys one universal test station that can test various types of DUTs. The universal test station includes large switching systems that interconnect a superset of the instruments that can test all the target DUTs.
AMETEK Programmable Power recently announced that Sam Hughes would be returning to the business as Vice President and Business Unit Manager. Sam is returning to Programmable Power after spending the last year as the Business Unit Manager for IntelliPower, where he led their successful integration into the AMETEK family. Prior to his time with IntelliPower, Sam served as Director, Global Services for AMETEK Programmable Power from 2019 to 2021.
AMETEK Programmable Power has introduced two new multiple-output programmable DC power supplies—the Sorensen™ Asterion® DC ASA Series and Sorensen™ Asterion® DC ASM Series. These bring high power density and flexibility to applications ranging from commercial functional PCBA tests to military ATE systems. Each supply in the two series comes in a 1U-high chassis and features up to three independent, isolated outputs.
AMETEK Programmable Power Reveals the New Sorensen™ Asterion® DC ASA Series
AMETEK Programmable Power is proud to reveal the new Sorensen™ Asterion® DC ASA Series Multiple-Output Programmable Power Supply. As the newest addition to the Asterion platform of power testing solutions, the ASA Series offers enhanced testing efficiency while drastically reducing space and power consumption requirements.
Semiconductors have been making headlines recently, primarily because chipmakers have been unable to make enough devices to satisfy demand. Headlines like these are common: “Until 2023? Parts shortage will keep auto prices sky-high,” “The global chip shortage is starting to hit the smartphone industry,” and “Why the global chip shortage is making it so hard to buy a PS5.”
When it comes to power and test applications, efficiency is key. The quicker you can perform tests, with the least amount of setup time and capital/energy costs, the more tests you can perform and the faster you can validate your product designs.
Here, the role of the power supply innovation is an important one. As a critical piece of any test application, a power supply can make or break your product testing. The following are just a few factors that are dependent on your choice of power supply:
White Paper Details How to Choose Air- and Water-Cooled Electronic Loads
If you are working in the renewable-energy field, you can benefit from using a programmable DC electronic load to test batteries, fuel cells, and solar panels. Even if you are working with more conventional energy sources, an electronic load can be a useful instrument to have on hand to test power supplies, battery chargers, ultracapacitors, and other devices that generate a DC voltage.
In the race for renewable energy, solar is gaining ground on wind generation, which currently holds a lead over solar. In its July “Short-term energy outlook,” the U.S. Energy Information Administration (EIA) estimates that next year, additional solar capacity coming online will exceed additional wind capacity for the first time, the EIA reports.
AMETEK Programmable Power Supports Team Sonnenwagen Aachen
Team Sonnenwagen Aachen, equipped with an Asterion DC programmable power supply from AMETEK Programmable Power, has spent nearly 14 months designing and building its third-generation solar-powered racecar, dubbed Covestro Photon. In October, team members will take the car to Morocco to compete with other European solar teams in a new event—the Solar Challenge Morocco 2021 (SCM). The SCM is a five-day event with five different stages covering 2,500 km.
It wouldn't be bragging to say that we have a lot of experience with power supplies here at AMETEK Programmable Power. Many of our design and sales engineers have been with us for a long time, and we feel that really gives us an edge when it comes to helping you get the best product for your needs. Their extensive knowledge of our products and applications enable them to recommend just the right products, and you can feel confident in their recommendations.
The power supply may be one of the least-considered components of an electronic system. After all, how hard can it be to find the right power source for your system? You figure out how much current you need at the voltage your system will operate at, find a model that can supply that voltage and current in a catalog or on a website, then make the purchase.
Choosing the right power supply for your test system or application is no small task. Defining the power requirements for your application comes first, but this is only the beginning. Once you know the voltages and currents, you need to figure out how to power and control your source. There are several decisions that will need to be made.
Modern education and research are essential to creating the technology of the future. Good education creates the next wave of engineers and scientists, while research gives us all the tools and new scientific understanding to fuel our best designs.
The wave of renewable energy is not coming – it is already here. Due to a mix of consumer and regulatory pressure, renewable energy is transforming the power and energy sector, creating new opportunities and challenges for design engineers.
The right power supply can make all the difference. When you are creating a new product or setting up a test system, how you power your designs can have a major impact on their performance, efficiency and energy usage. Making the wrong choice can lead to:
If you want to create next-level products in the military and aerospace sector, then you need better power and testing solutions. Only with the right power and test equipment can you respond to the industry’s rising demands with qualified products that meet performance and efficiency requirements, while also upholding government regulations.
Performance. Reliance. Brilliance.
Inspired by the enduring power of a brilliant star, the California Instruments Asterion line of AC power sources by AMETEK Programmable Power combines intelligence and flexibility to create an advanced platform of AC solutions. This easy-to-configure design features sophisticated technology for delivering high performance, programmable AC and DC power. Its sleek design packs maximum power density into a low-profile form factor with an intuitive touch screen interface placing that power at your fingertips. Centralized control and unparalleled modularity make Asterion the most adaptable platform on the market. Its groundbreaking capabilities set the standard for affordable, precision power sources.
Creating a multi-phase system with single-phase Asterion AC power sources is simple, but there are several options available for control and communications. Configuring parallel groups of Asterion AC power sources is also straightforward. This technical note provides the required information to successfully configure your Asterion AC in multi-phase or parallel groups with the available communication options.
While today’s power supplies provide many advanced features, finding them and maximizing their capabilities can be challenging. That’s why when AMETEK Programmable Power designed the Sorensen™ SGX Series programmable DC power supplies, we paid a lot of attention to the user interface. The result? The SGX Series has an intuitive, easy-to-use front panel touchscreen display that allows you to quickly access output programming parameters, measurements, sequencing, and configuration and system settings.
One feature that makes the California Instruments™ Asterion® AC Series power sources an ideal choice for sophisticated test applications is their ability to manage test waveforms. In addition to providing the three standard waveforms — sine wave, square wave, and clipped sine wave — the Asterion AC Series has an arbitrary waveform generator that allows you to create up to 200 different custom waveforms and download them into the power source memory.
TheSorensen SGX Seriescombines onboard intelligent controls with the outstanding power electronics common to all SG family supplies. These controls enable sophisticated sequencing, constant power mode and save/recall of instrument settings. The ability to program sequences and loop through them makes the SGX ideal for repetitive testing.
One of the cool features of AMETEK Programmable Power's SGX Series of power supplies is that it supports an LXI Class C Ethernet interface. This allows you to connect the SGX Series to your network and control it remotely from any computer on the network.
The AMETEK Programmable Power AMECare® Reliability Assurance™ service level agreement (SLA) program is designed to provide “white glove” support for mission-critical power and test devices. It includes regular preventative maintenance, break-fix support, and legacy upgrades beginning with a product’s purchase and extending throughout its entire lifecycle.
Resistive loads are easy on a DC power supply. When you turn off the power, the current quickly drops to zero and no damage is done.
Over the past 10-20 years, counterfeit electronic components have become a serious problem. Counterfeit components are parts that have somehow been misrepresented as to their origins or quality. Because counterfeit parts are often of lower quality than what are called “franchise” parts, they may represent a hazard if used in critical systems such as automobiles, aircraft of any kind, military equipment, or space vehicles.
Designing equipment to be operated onboard Navy vessels is not like designing a consumer product that plugs into a three-prong wall socket. That being said, it’s important to know the characteristics of the on-board power source and test to make sure that equipment can reliably use that power.
Testing AC power sources, such as uninterruptible power supplies, can be a real challenge. These products are often tested with resistive load banks, but this approach does not simulate real-world conditions such as switching DC/AC converters found in many AC powered products.
AMETEK Programmable Power, the global leader in programmable AC and DC power test solutions, will be exhibiting at APEC 2019, which takes place this year from March 17 – 21 in Anaheim, CA at the Anaheim Convention Center.
We have just added two new higher-power models to our Asterion™ line of AC power sources:
Aircraft electronics and other electrically-powered equipment must be tested under extreme power conditions to ensure it will operate reliably once in the air. In the military world, MIL-STD-704 (now up to rev. F), ‘Aircraft Electric Power Characteristics’, establishes the requirements and characteristics of aircraft electric power.
Energy and power generation has evolved into one of the key growth industries of the 21st century. Customers depend on AMETEK VTI Instruments data acquisition and monitoring instruments and AMETEK Programmable Power power sources to deliver the accuracy and precision required to develop highly efficient and reliable products and gain a competitive edge in the global energy market.
The Sorensen SG Series is designed for exceptional load transient response, low noise and the highest power density in the industry. With a full 15 kW available down to 20VDC output in a 3U package the SG Series leads the industry in power density. The power density is enhanced by a stylish front air intake allowing supplies to be stacked without any required clearance between units.
The Sorensen™ SGX Series is the next generation of our successful SG Series of programmable DC power supplies. Like the SG Series, the SGX Series has exceptional load transient response, very low noise, and high power density. What sets the SGX Series apart is the new touch screen display. This new feature makes the Sorensen SG Series of programmable DC power supplies even easier to use.
Today, when we think about controlling the output of a power supply, we usually think about digital control via a USB port or some other network interface. That's not the only way to control a power supply, though. Analog control is still used in many industrial applications, and it’s also a good choice if you have fairly simple control needs.
For most benchtop power supply applications, the most important feature is a user interface that allows an engineer or technician to set up the power supply quickly and easily using the front panel. Benchtop power supplies, like the Sorensen XEL Series, have this kind of interface. For example, the XEL Series has a fine control knob for setting the output voltage very accurately and an output enable switch, which lets you set up the desired voltage and current levels prior to actually turning on the output.
While electronics technologies have come and gone, mounting them in 19-in. racks is as popular as ever. There are various theories over the origin of the 19-in. rack, but Practical-Home-Theater-Guide.com says that George Westinghouse used 19-in racks in 1890s to mount railroad relays. Then, in the early 1900s, telephone companies designed their switches to fit in 19-in. racks.
The success of a product often depends on how well it can handle power transients. To make this testing easier, AMETEK Programmable Power's Asterion AC Series makes it easy for users to create custom waveforms that include transients.
When one of our standard products cannot completely satisfy your requirements, AMETEK Programmable Power can design a custom power supply system for you. The solutions range from OEM integration for medical and semiconductor industries to modular avionics ATE power subsystems to turnkey solar array simulators for satellites.
We also can modify our standard power supplies to meet your application requirements.
The Sorensen DLM 600 Series of programmable power supplies is designed to provide continuously variable output voltage and current for a broad range of applications in a compact 1U (1.75 inches) high, half-rack (8.5 inch) wide chassis. The DLM 600 power supply series is ideal for high density, multiple output, rack-mount applications or low profile benchtop applications. Output voltages from 0-5 VDC to 0-300 VDC and currents from 0-2 A to 0-75 A are available.
Power systems operate at frequencies of 50 or 60Hz, but some devices, including personal computers, printers, and some industrial equipment, present a non-linear load and create currents and voltages with frequencies at harmonic frequencies. These harmonics get fed back into the power system and can cause other devices connected to the power source to malfunction. There are several standards that specify the level of harmonics that a particular device can produce.
The most important thing that a power supply does is to maintain a constant voltage output or a constant current output. This is true whether the power supply is built into a product and provides fixed output voltages, such as a desktop computer power supply, or a power supply that is on the test bench or is part of an automated test system that must provide variable outputs. We call this ability to maintain a constant output voltage or current regulation.
One of the big challenges when designing and manufacturing auto parts is ensuring that they operate reliably in very hot environments, such as Dubai, where the high temperature can easily reach 40˚C. Of course, they must also operate reliably in very cold environments, such as Siberia, where the thermometer can drop to -40˚C or below. You certainly don't want parts to fail when you're zipping down the road at 200 km/hr. because they can't take the heat (or the cold).
Electronic loads are used in a variety of tests, including power supply tests and battery tests. You can program them to provide exactly the kind of load that you need for the device you are testing.
Low-level measurements are susceptible to noise from a number of different sources.
The tests you run to ensure that airborne utilization equipment is compatible with an aircraft's power system are specified in a series of MIL-HDBKs, specifically MIL-HDBK-704-1 through MIL-HDBK-704-8. To run these tests, a sophisticated power source is essential to simulate various power conditions. In addition, you also need whatever equipment is required to monitor the unit under test (UUT) while running the test.
AMETEK Programmable Power DC power supplies convert AC power to DC power. While our supplies are very good at doing this, they're not perfect. On the output, there will be some small amount of AC still present. This is called ripple.
As the number of photovoltaic power-generation systems continue to increase, the requirements for photovoltaic inverters are evolving as well. Conventional electrical characteristics such as over-voltage, over-frequency, anti- islanding intended to verify the inverter’s ability to tolerate power grid fluctuation are changing to meet varying requirements of the modern grid. In addition, the introduction of new requirements for low voltage ride through, high voltage crossing, and reactive power injection mean the inverter must be able to provide appropriate compensation when these grid conditions occur.
When installing an AMETEK Programmable Power power source, you must properly size the wires you use to connect the AC input power to the power source and the AC or DC output to the load. Selecting the right size gauge wire will ensure that your power source will operate efficiently and reliably.
To ensure that aircraft electronics and other electrically-powered equipment will operate reliably once in the air, you must test them under extreme power conditions. In the military world, MIL-STD-704 (now up to rev. F), “Aircraft Electric Power Characteristics,” establishes the requirements and characteristics of aircraft electric power.
Test costs can add considerably to overall manufacturing costs, especially when extensive testing is required. That's why it's important to keep test costs to a minimum. Reduced test costs translate to lower manufacturing costs. Modern power supplies, such as California Instruments' Asterion AC Series, have several features that can help you reduce test costs:
AMETEK Programmable Power has added a 22.5 kVA unit to its popular California Instruments MX Series II AC/DC Power Sources. The MX22.5 delivers up to 22.5 kVA and can be configured to have single-phase or three-phase outputs in AC, DC or AC+DC mode. The MX22.5 is more economical than the California Instruments MX30, while at the same time offers more features and higher output power than the product family’s MX15 model.
Many op-amp circuits used in analog applications, such as signal conditioning for high bit count analog-to-digital converters require the use of both positive and negative power supply voltages, as shown in Figure 1. Supplying both positive and negative voltages allows input signals and output signals to swing both positive and negative. You could power these circuits with an adjustable power supply with two outputs and adjust them separately—one to the positive rail voltage, say +12 VDC or +15 VDC and the other to a similar negative voltage.
Often the selection of programmable power supplies is based upon how high a voltage it can produce or how much current it can source. When selecting an electronic load, however, you need to consider not only volts and amps, but power as well.
Although power supplies are most often used in a single location, such as a design lab or a factory test station, there are times when portability is desirable.
Test bench power supplies, like the Sorensen XBT Series, are more than just power supplies. They are versatile test instruments that you can use to make your life simpler. Here are four things that you can do with Sorensen test bench power supplies that just might make your tests more effective.
One of the problems we frequently encounter in the field is that power supply users fail to take into account the voltage drop in the wires connecting a power supply to a device under test (DUT) or other electronic system. When a load draws a high current, the voltage drop across the power leads could be high enough to cause a device under test to fail or cause a system to malfunction.
Two terms that often get bandied about when describing automated test systems are resolution and accuracy. To get the best results from your power supplies, it is important to understand the difference between these two specifications and how they affect your system.
One of the most common applications for AMETEK Programmable Power power sources is some kind of automatic test system. The California Instruments Asterion AC Series, for example, was designed to be used in commercial and military avionics test system, manufacturing and process control, and IEC standards test systems. It includes Ethernet, USB and RS232 standard control interfaces, and there is an optional IEEE-488 (GPIB) control interface available.
To select the right power source for your applications, one of the first things that you must do is to figure out how much output power you need. For a DC supply, this is relatively straightforward. You first determine the highest output voltage you'll need and then the highest output current that you'll need.
Electronic loads, such as the Sorensen SL Series of DC Electronic Loads, are instruments that you would use to provide a programmable load when testing voltage and current sources, including power supplies and batteries. Modern electronic loads are actually sophisticated electronic test instruments that can offer a number of different modes, including Constant Current (CC) mode, Constant Resistance (CR) mode, Constant Voltage (CV) mode, and Constant Power (CP) mode.
While these days, computer control is usually the preferred method of controlling a power supply, many AMETEK Programmable Power products, such as the Sorensen SGA Series still offer analog control. Analog control is still used in many industrial applications, and it's also a good choice if you have fairly simple control needs.
Many of AMETEK Programmable Power's AC power sources are designed to work as both standalone units and in multi-box configurations. The California Instruments iX Series AC/DC power sources, for example, includes independent 5 kVA power modules that can be combined into a number of configurations. You might use a single unit as a high-power, single-phase system or configure three units to form a medium-power, three-phase system. This modularity allows you to build a power system that meets your specific needs.
The Elgar GUPS Series of uninterruptible power supplies are ruggedized on-line UPSs that accept a broad range of worldwide utility and military AC input power. Without operator intervention, they automatically select the appropriate input power ranges to accommodate global operation. The batteries used in the GUPS Series units are a spiral wound, valve-regulated, lead-acid batteries. While the unit itself maximizes battery life with automatic, microprocessor-controlled equalization and temperature compensation during charging, there are steps that users can take to extend UPS battery life even more.
In Part I, we introduced you to the concept of testing equipment for immunity to voltage dips and short power interruptions in accordance with IEC 61000-4-111. In addition to specifying the test waveforms, the standard also specifies AC source requirements for full compliance testing.
Mains voltage dips and short interruptions can be caused by a wide variety of phenomena and can cause equipment to operate unreliability, and in some cases, can damage the equipment. Faulty loads on an adjacent branch circuit, for example, can cause a circuit breaker to trip, and high-power loads such as welders, motors and electric heaters can cause voltage variations. Natural events, such as power lines downed by storms or lightning strikes, may also disrupt mains power.
To ensure that automotive electronics can withstand the voltage transients induced on the power bus, companies use expensive arbitrary waveform generation and coupling networks during the design phase. For production test, however, a simpler and less expensive means for simulating bus voltage variations and transients is required. For many transient tests, all you need is a switching power supply and an electronic load.
The Sorensen SG Series is one of the most popular high power programmable DC power supplies on the market. The SG Series is designed for exceptional load transient response and low noise output. With a full 15 kW available down to 20VDC output in a 3U package the SG Series leads the industry in power density. The power density is enhanced by a stylish front air intake allowing supplies to be stacked without clearance between units.
Programmable AC power sources are primarily used to provide a low distortion, precisely controlled sinusoidal voltage to a unit under test, but some AC sources, such as the California Instruments I-iX Series II, perform measurements as well. Part 1 describes the benefits of using sources for measurement and how to make voltage and current measurements. Part 2 describes how to make frequency and power measurements. In Part 3, we'll discuss how to make power factor and crest factor measurements using an AC power source.
Programmable AC power sources are primarily used to provide a low distortion, precisely controlled sinusoidal voltage to a unit under test, but some AC sources, such as the California Instruments I-iX Series II, perform measurements as well. Part 1 describes the benefits of using sources for measurement and how to make voltage and current measurements. In Part 2, we'll discuss how to make frequency and power measurements.
The California Instruments iX Series AC/DC Power Source / Analyzer delivers AC, DC, and AC+DC, transient waveforms and performs complex power measurements. While the standard frequency range of the iX Series is 16-500 Hz, it can deliver AC power at up to 1,000 Hz. Many applications, including commercial and military avionics testing, require an output frequency of 800 Hz. The avionics test standards that specify tests at this frequency include:
Programmable AC power sources are primarily used to provide a low distortion, precisely controlled sinusoidal voltage to a unit under test. Increasingly, however, AC sources, such as the California Instruments I-iX Series II, are being used to perform measurements as well. The tight integration between AC source (stimulus) and measurements (response) provides several benefits:
Providing AC power to your AMETEK Programmable Power source can be confusing. The reason for this is that there are several different configurations for three-phase power. What you first need to do is to identifying the different power configurations that may be in your facility and then decide how to connect it to your power source.
Modern electronic loads, such as the SL Series, are versatile test instruments that should be part of every test engineer's toolbox. Here are some tips on how to use them properly.
In many applications, a DC power supply has to drive a load with a large ripple component. Examples of this type of load are DC-AC inverters, DC-DC converters, and DC motor loads. Linear supplies can normally handle this kind of load easily, but when you use a switching power supply, such as the Sorensen SG Series or Sorensen ASD Series, to drive this type of load, you may encounter some unexpected (and undesirable) problems.
At AMETEK Programmable Power, we are committed to helping you select the best AC power source for your test system, even if you're not currently an expert on AC power. The first thing that you need to know are the terms used by AC power engineers. Below, you'll find definitions for the three most basic AC power terms you'll need to know: true power, apparent power, and power factor.
The nature of the load that will be connected to the AC power source is very important in determining the correct type of supply. Generally loads can be classified as linear or non-linear. Linear loads consist exclusively of reactive, inductive or resistive components and can thus be modeled as an LCR network.
Solar Array Simulation Enables Better PV Inverter Testing for Manufacturers
To ensure that aircraft electronics and other electrically-powered equipment will operate reliably, you must test them under extreme power conditions. In the military world, MIL-STD-704 (now up to rev. F), “Aircraft Electric Power Characteristics,” establishes the requirements and characteristics of aircraft electric power. It deals strictly with power quality, and does not say anything about electromagnetic interference.
Selecting a laboratory power supply for the lab is not as easy as you might think. If you thumb through a catalog and choose the first one that you think meets your needs, you could end up with a power supply that more often than not sits on the shelf. By filling out the checklist below, and comparing your needs to the product descriptions and specifications of AMETEK Programmable Power's DC bench supplies, you're more likely to get the power supply you need.
Transient response is a measure of how well a DC supply, such as the Sorensen SG Series, copes with changes in current demand or how well the supply follows load impedance changes. This is an important specification in many applications, such as mobile phone testing and testing automotive relays and fuses. A good understanding of this power supply characteristic will help you choose the right supply for your test application.
Electronic loads have many different applications, including testing power converters and modulating a current supply while performing other tests. They are easy-to-use and provide much higher throughput than resistors when varying loads are needed.
While switch-mode power supplies have many advantages, one of their disadvantages is that they are a non-linear load, and because of that can inject harmonic currents into the electrical distribution system. Devices with switching supplies include domestic appliances (TVs, microwave ovens, lighting equipment and dimmers), and office equipment (PCs, printers). Motor-driven equipment can also cause harmonic distortion.
The most common operating mode for AC power sources is to provide controlled power to electrical products under test. In this mode, the power source simply replaces utility-supplied AC line power, whether 120V-60Hz “North American type” power, 220/230V-50Hz used in most of Asia, South America and Europe, or 100V-50/60Hz used in Japan.
When a load draws a high current, the voltage drop across the power leads could be high enough to cause a device under test (DUT) to fail or cause a system to malfunction. The solution to this problem is to use remote sensing. By adding a second set of wires—the sense wires—you can ensure that the proper voltage level is at the DUT or system's power terminals.
You can use electronic loads to test many different devices, including
Many AC-powered products, such as switching power supplies and electronic lighting ballasts, draw high start-up currents to charge capacitive circuitry. Excessive inrush currents not only cause lights to flicker, but can also damage the unit. It's important, therefore, to be able to measure inrush currents to get a handle on this problem.
In order to perform an accurate test of solar array inverters, the output of a solar array simulator must faithfully follow the I-V curve of a solar array or solar panel. That is to say that it must respond just as a solar array would to the changing load conditions imposed by the inverter under test. In order to evaluate how well a simulator can do this, you need to consider three parameters: output noise current, phase error between output voltage and current, and the maximum power point (MPP) tracking accuracy.
One of the most important specifications for a DC power supply is load regulation. Load regulation is a measure of how well a supply maintains its output voltage when the output current changes. Good load regulation will help ensure that the power supply will deliver the voltage your circuit or system needs.
The slew rate of a DC power supply is the rate at which the output voltage and output current changes. This characteristic is important in many applications, especially automatic test applications, as the faster a supply reaches a programmed voltage or current, the faster a test will run.
The first choice you must make when purchasing a DC power supply for a test system is whether to select a linear supply or switching supply. Linear power supplies offer low ripple and noise specifications and have fast transient behavior. They are, however, inefficient and generate a lot of heat. They are also quite heavy. As a result, most engineers find them desirable only at lower output power levels (typically less then 500 Watts). Most linear DC power supplies are benchtop supplies.
Testing the electric motors and the electronic control modules found in today's electric vehicles (EVs) and hybrid electric vehicles (HEVs) is in many ways more challenging than testing internal combustion engines and their control modules. For one thing, HEV electric motors spin faster than internal combustion engines. They also must change speed more rapidly than internal combustion engines, and because some are designed to also generate energy, the test system must also measure the electrical output as well as the mechanical output of the motor.
The crest factor of an AC current waveform is the ratio of waveform's peak value to its rms value:
Say that we have a circuit with a power supply and an inductive load on it. From the instant that electrical power is supplied to the circuit, the inductive load will accumulate stored energy. If an attempt is made to open the path with a switch, this energy will generate a high reverse voltage and arc across the contacts of the switch. This could damage the switch, load and other circuit components.
