By Jon Semancik, Director of Marketing, AMETEK/VTI Instruments
When you purchase a power supply, you need to take into account more than just the price of the supply. The price is just one of the factors in the total cost of ownership. Other factors include:
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 makes it easy for users to create custom waveforms that include transients. The output waveforms can include any or all of the following transients:
Topics: AC Power Sources
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.
Low-level measurements are susceptible to noise from a number of different sources. While discussing all the ways that noise can degrade low-level measurements is outside the scope of this article, let's at least consider how to make sure that your test system power supply is not a problem:
As noted in an earlier blog post, 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.
Topics: AC Power Sources
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. This standard is not only used by the U.S. military and military contractors, but has also been adopted, either directly or indirectly, worldwide. For example, the Chinese standard, GJB 181, Characteristics of aircraft electrical power supplies and requirements for utilization equipment, is largely based on MIL-STD-704.