Using non-isolated DC/DC converters?

[Arthurc]

How much should I worry about noise put onto my 12v system by a DC to DC voltage converter? I’m using a few of them to both step up to 48v for Poe hubs and down to 5v for usb powered devices but as I went to install one to step up to 19v for my monitors I realized they aren’t isolated, meaning they share a ground with the 12v system.

I haven’t seen any issues yet, is this something that I should worry about or is truly isolating the systems not worth it?

Thanks!
Arthur

 

[twistedtree]

I've never had any issues with them, and am not sure that an isolated output would necessarily reduce noise. I think they are really intended for applications where the input and output need to have different negative potentials.

 

[Arthurc]

Ok thanks, a buddy mentioned it and it made me wonder. I’d assume my n2k network and vhf would have issues first and I haven’t seen any problems.
AC

 

[stevemitchell]

I've used both isolated and non-isolated, but for the reasons @twistedtree mentions. The non-isolated are a bit cheaper, and have one less wire, which is nice.