At Daburn, we sometimes hear from customers with an unfortunate dilemma: "I need to operate the power supply outside its rated specification."
While we don't recommend disregarding the power supply's specifications, we do our best to provide you with as many safe options as possible.
One such example is when a customer wants to use a linear power supply at a lower input voltage than what's listed on the data sheet. Here's an overview of the risks associated with undervoltage, along with a sound strategy for selecting a linear power supply.
Linear power supplies can be an attractive choice for applications requiring low output power, low noise, low ripple and fast transient response, to name a few. These typically cost-effective units also boast a simple design and high reliability. Because linear power supplies typically have a narrow input voltage range, it may be difficult to specify a unit that can accept a low input voltage when needed.
Undervoltage occurs when the average voltage drops 10% below the system's rated voltage for more than one minute. Various components will carry more current, resulting in overheating and damaged or poorly performing components. Potential damage could also include distortions or even cracks to the linear supply's casing as well as much lower efficiency. And, keep in mind that operating a power supply outside of its rated specs can potentially void the warranty.
Although it may be difficult to find a linear power supply with a universal input, it pays to partner with a power supply vendor that offers a wide range of inputs early in the design process. With more inputs to work with, your supplier can offer more modification options and better tailor the transformer to your required input voltage to avoid overheating and associated damage.
At Daburn, our standard Polytron linear encapsulated power modules are available in five different input voltages — 100, 220, 230, 240V AC and a switchable dual input voltage of 115/220V AC — and output voltages ranging from 5 to 250V DC. Keep in mind that many other manufacturers do not offer switchable dual input units.
Linear power supplies are less forgiving for operating outside their rated specs than other power supply types. And If your needs fall outside our range, get in touch with us early in the process to avoid last-minute worries. We can make small changes to approach your required input voltage.
Polytron linear power modules feature a high isolation voltage option, short-circuit protection, and super low noise, as well as optional sockets or bench adaptors built for single and dual linear power supplies. They also offer alternative pin configurations, a switching frequency of 50 to 60 Hz, with 400 Hz as an option, isolation resistance of 50 MOhms and free air convection.
Medical versions are also available, which are compliant to IEC 60601-1, CE-certified, and feature 2X MOPP insulation, up to 5700V DC IO isolation and very low RMS output noise.
For more information about Daburn-Polytron linear power supply modules, please visit our product page.