Personally, I ground one side of every power supply. In this case, you would be fine grounding the – OUT of the RSD.
Most DC-DC converters have floating outputs. I have used a Traco TCL 060-124 DC to do what you want. If you are going from 24 to 48, there are fewer choices. From: Jason McKemie Sent: Wednesday, August 19, 2015 4:11 PM To: af@afmug.com Subject: Re: [AFMUG] Mixing +48v and -48v I'll probably just float the ground. On Wednesday, August 19, 2015, Josh Baird <joshba...@gmail.com> wrote: They are hard to find. Where will you ground the MT in this type of scenario (with an RSD in between your -48V rectifier and MT)? Josh On Tue, Aug 18, 2015 at 11:31 PM, Jason McKemie <javascript:_e(%7B%7D,'cvml','j.mcke...@veloxinetbroadband.com');> wrote: It actually looks like the RSD-100C-24 should do the trick (I'm dropping to 24v, so I guess my subject line wasn't exactly correct). My normal source is out of those, according to their website they have some RSD-200C-48 units though. On Tue, Aug 18, 2015 at 7:58 PM, George Skorup <javascript:_e(%7B%7D,'cvml','geo...@cbcast.com');> wrote: The Mean Well RSD gives 4kV i/o isolation and will work perfectly this, no grounding issues. I think the smallest you can get in 48/48 is 200W, the RSD-200C-48. Good luck finding some. On 8/18/2015 7:20 PM, Jason McKemie wrote: I'm wanting to power a mikrotik switch off of a -48v rectifier setup that already has some -48v equipment running on it. I'll be using a Meanwell DC/DC converter, which appears to not bond anything with the ground. The mikrotik, however, does bond the negative with ground. Do I need to keep the mikrotik's ground isolated from the main ground? Or is the DC/DC converter going to keep things from going boom?