Probing around for a powerful 48vdc supply solution I landed on a fair priced Eltek Flatpack2 rack unit. I know, it is an overkill for HAM shack use with its 8kw of DC output power. But as Jeremy Clarkson says; quote “Power and speed solves many things”  🙂
Anyways, this really is a part of a telecom UPS system, and telecom 48vdc system has negative distribution with positive common return rail. This is the opposite of what we HAM usual needs, so it has to be rewired, or re-bared rather.
This is a 2U rack module with a smartpack2 controller and 4 x Flatpack2 2000w HE rectifier units. You can run a single rectifier without the controller but it will default to about 53,5 volts. In order to change the operating output voltage, you need the smartpack2 controller.
With the factory access password, you can with the controller permanently write new settings down to the rectifier, and it will default to any valid voltage value. Of course it is possible to hack and reverse engineer the eltek CAN-bus protocol with other tools. I know the e-bike community has done it.

Here are some pix:

Smartpack2 rack without load fuses cover panel.

Smartpack2 rack unit

Original common positive (+) return bar.

Rewired to common (-) negative return bar.

Load fuses

Complete unit

PowerSuite for M$ windows config and monitoring tool.