DC-DC buck converter to reduce voltage to loads. was : I'll share this with you

[Rover]

Yes, they claim 98% efficiencies like solar charge controllers take that with a grain of salt. I trust your opinions but you are talking in hundred of volts I'm talking 1 to 3VDC. Voltage converters are made to step up or down voltages if you step down 14.3 VDC to 12.3 VDC they are very efficient as opposed to 27 VDC to 12 VDC but still very little loss when compared to hundreds of volts. If you have a small load on a 36 VDC or 48 VDC system a voltage converter will run the loads with little fuss and very little loss.

They claim 98% efficient for a 24 VDC to 12 VDC voltage converter for the 36 VDC and 48 VDC models a little less but used in the proper design they can be useful.

My reason for sharing this with the group is to share information with them. Voltage converters can step up voltage (12 VDC to 48 VDC) or step down (24 VDC to 12 VDC) or what ever you need. 12 VDC models are cheaper because they are used the most.

[Rover]

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[Mike90250]

So, Rover - I'd like you to post a link to this magic part that is going to save you power/heat. I want to look at the data sheet and see how they do it.

Then I'll explain that you are simply moving the losses around from the LED drivers to the DC-DC converters. Yes it works. But you are not saving anything and in fact, most likely increasing losses by adding a redundant converter into the system.

[Rover]

Yes, they claim 98% efficiencies like solar charge controllers take that with a grain of salt. I trust your opinions but you are talking in hundred of volts I'm talking 1 to 3VDC. Voltage converters are made to step up or down voltages if you step down 14.3 VDC to 12.3 VDC they are very efficient as opposed to 27 VDC to 12 VDC but still very little loss when compared to hundreds of volts. If you have a small load on a 36 VDC or 48 VDC system a voltage converter will run the loads with little fuss and very little loss.

They claim 98% efficient for a 24 VDC to 12 VDC voltage converter for the 36 VDC and 48 VDC models a little less but used in the proper design they can be useful.

My reason for sharing this with the group is to share information with them. Voltage converters can step up voltage (12 VDC to 48 VDC) or step down (24 VDC to 12 VDC) or what ever you need. 12 VDC models are cheaper because they are used the most.

[bob-n]

Thank you for the tips. I think we all agree with what you're saying, but may have some misunderstandings about taking it to various specific situations.

We agree that switching converters can be very efficient. We agree that switching from 14V to 12V is more efficient than switching from 24V to 12V. We agree that you can convert from virtually any voltage to any other voltage with a switching converter, both up convert, down convert, and buck/boost if you're not sure about the input range or need to deal with a wide range.

When people quote 98% efficiency, I get skeptical. I've measured quite a few and they may have efficiency peak near that level, but 95% is much more prevalent, especially when you run the converter over a wide load range. Here's an example of efficiency vs current for a converter running 12V in, 5V out or 9V out:
efficiency.jpg
The real point of contention is whether adding a switching converter to an existing system will make the system better. That is very dependent on the existing system. I think Mike is already dealing with very efficient systems, and is skeptical that adding another converter will help.

But yes, there are many situations where adding a converter solves the problem for very little money and with very low loss. Is that what you're saying?