230VDC to 10VDC Converter Circuit 5 Amp Intermittent

Easiest solution: go buy a 5A 10VDC power supply. Someone makes one.

JReaf is right. If you want 50 Watts of power at 10 volts, you will spend more money trying to do this yourself using individual components. And you will most likely have to waste a lot of excess power to get your 50 Watts. If the voltage difference was much closer like 20 VDC to 10 VDC it becomes more reasonable and might be worth the effort.

With so many products available that have had all the design considerations built in, you would be waisting your time and money to attempt this on your own.

Good idea NotUrOrdinaryJoe.

This is the situation. The only available power supply in such space area of installation is 230VDC which is intermittently turned on and off [75% continuously cycling ...] On this space area is a need to power a device drawing a 5A load at 10VDC. Actually I had one...and another one...but they all burnt because they are not designed for the intermittent factor of being turned on and off...24 hours all week...

any advice is a relief...

Good idea JRaef and NotUrOrdinaryJoe

This is the situation. The only available power supply in such space area of installation is 230VDC which is intermittently turned on and off [75% continuously cycling ...] On this space area is a need to power a device drawing a 5A load at 10VDC. Actually I had one...and another one...but they all burnt because they are not designed for the intermittent factor of being turned on and off...24 hours all week...

any advice is a relief...

Let me see if I have this right. You want to feed continuous power to some device that draws 10 volts at 5 amps, but your only supply is 230 VDC which is only on for 7.5 minutes out of every 32.5 minutes? If that is correct you will need to draw 50 WattHours plus losses from the 230 VDC supply?

How are you doing this now? I would expect that you might have tried a UPS (un-interruptible power supply) and then a 10VDC power supply? If this is what you used, you are wearing out the battery in the UPS. What you need, instead of a battery, is called an ultracapacitor which will out perform a battery. Problem is that not a lot of people make that type of UPS. You may have to do some calling to get what you want, but first you should do a search using the following keywords " UPS ultracapacitor " in the search box.