A power supply unit (PSU) is a vital part of any electronic device, but it’s especially important in medical devices. Medical device PSUs provide a stable and regulated voltage necessary for function and safety. Depending on the type of device manufacturers are working on, standard PSU options may not completely meet their project’s specific requirements. You might wonder if a customized power supply is right for you, and if so, how much customization you may need.
What are Customized Power Supply Options?
If needed, a medical device manufacturer could customize every part of their PSU to meet exact specifications. However, the question you should be asking is not about how much you can customize, but instead, how much you should customize.
The output of a power supply is easily customizable, but changing the internal parts of a PSU is much more complicated. This is because manufacturers will have to go through UL approval with these devices if they start to change too much about the power supply. Having to go through additional approval can extend the timeline significantly if the customization is too extensive. It’s better to simplify your process and find slight customization options that can work with your device.
Common Power Supply Customizations and Additional Considerations
Outputs
Most commonly, cable connectors and lengths on ATX and SFX power supplies can be easily customized to fit your needs. The best place to find help with this is through a medical-grade manufacturer who makes power supplies to order. At RAM Technologies, we have a range of standard output harnesses, but we also customize short-run orders for customers. In fact, most of the units we’ve produced have “non-standard” output harnesses. While most PSU companies don’t accommodate 5-volt or 12-volt barrel jacks as part of their standard offerings, for example, RAM has fulfilled these two requests recently.
Cable Lengths
Custom lengths for cables can also be important when your medical device is in an environment with specific spatial needs. Most cables that RAM Technologies offers, for instance, have 3 or 4 standard length variations. However, we can further customize this to meet needs that fall outside of what is included on the product sheets. Lengths are measured starting at the exit point of the power supply and running to the base of the connector housing, so there is a give or take of 1 inch on these measurements.
Reliability
Many companies that offer medical-grade PSUs also focus on other industries and power supply types. While they’re certified to meet medical standards, their design is still focused primarily on the commercial PC market. This means that the power supplies tend to have a lower mean time between failures (MTBF) of around 100,000 to 200,000 hours, while RAM PSUs have demonstrated MTBF of over 500,000 hours, even consistently calculating at close to one million hours. So, even with ISO9001 certification and strict adherence to UL60601-1, IEC 60601-1, and EN 60601-1 regulations, you may find differences in MTBF between companies focused on more than one industry and one that is focused solely on the medical field.
Another important factor to consider alongside customization is reliability. A medical-grade PSU manufacturer should be focused on high MTBF and the redundancies necessary to make this possible. Our power supplies have two fans to improve airflow and add redundancy in case one fan fails.
Guarantees
If you use a PSU in your medical device and it’s no longer being produced when you want to create more devices, you’ll have to take your device through the approval process again in the markets where you are looking to sell – FDA for the US, for example. This can be even more difficult when you’ve worked on a customized power supply, because you’ll have to find the customization you need again and then go through the approval process. Because RAM Technologies is focused only on medical-grade PC-based power supplies, we guarantee that the PSU we make for you will be available through the lifetime of your product.
RAM PFC275-48 – Our Custom 275-Watt Power Supply
In addition to creating custom outputs and cables, RAM Technologies has also partnered with a customer to make the PFC275-48, a 48 Vdc, 275-watt medical-grade ATX power supply. This PSU was specifically designed to deliver power at long distances, through distribution cables as long as 100 feet. The PFC275-48 boasts tight point-of-load regulation, thanks to its remote sense lines. This means the voltage remains consistent even with cable resistance, ensuring your devices receive the precise power they need to function correctly. It also has dual fans with Smart Fan technology. This system automatically adjusts fan speed based on temperature, providing optimal cooling while minimizing noise distraction.
If you’re in the mode of deciding whether to build or buy a power supply, or you’re weighing your customization options with vendors, we can help you get to the next step. Contact us and we’ll go over the options that will suit you best.
RAM Technologies’ power supplies are 60601-1 3.2 certified. When you’re designing your medical device and need help with a PSU, contact us for details.
More Resources:
Custom Medical Power Supplies
Custom Power Supply Cables for Medical Devices
Buy vs. Build: Power Supply Options
