Fuse and distribution for 48v loads (inc 48-12 converter)


New Member
Jul 30, 2021
I am planning a 48v battery system that includes a few 48v loads. I'm trying to understand the options for fuse to protect the wires to the 48v loads.

The loads are:
1. 48v-12v 30amp Orion converter (draws 10amp at 48v)
2. A 48v HVAC system (draws max 30amp at 48v)
3. Possibly a 48v hot water element (drawing, say, 15amp at 48v)

So looking for fuse options similar to 12v loads, but it seems that fuses are voltage sensitive (learning stuff all the time :). Options found so far:

0. Victron Lynx Distribution (not an option because only MEGA fuses at high amps, or DIY make Midi fuses fit, but unit is massive and not needed for the smaller wires in a 48v system).
1. MBRF terminal fuses (but only go down to 30amps). e.g., https://www.bluesea.com/products/5196/MRBF_Surface_Mount_Fuse_Block_-_Common_Source
2. Victron MIDI fuses (but only go down to 30amps, shown in the price list as "MIDI-fuse 30A/58V for 48V products")
3. Auto "58v" MINI fuses (good range of smaller sizes up to 30amps). e.g., https://www.littelfuse.com/products/fuses/automotive-passenger-car/blade-fuses/997.aspx

Each requires a different kind of holder. I was hoping for a "power distribution" bus bar approach (like the MBRF one above and the Victron Lynx Distribution. There seem to be those options for the MBRF, but I'm particularly confused about the MINI 58v fuses. Can those 58v MINI fuses fit in the MINI fuse distribution panels? ie something like this: https://ceautoelectricsupply.com/wp-content/uploads/2016/06/MINI_Fuse_Block_with_Cover.jpg Does anyone know a high quality option (Bussman, EATON, Blue Sea etc)?

Failing that should I just use a bus bar with multiple inline fuse holders. e.g., The littelfuse FHM2 https://www.littelfuse.com/media?re...=littelfuse-fuse-holder-inline-mini-datasheet

Or should I go with the MBRF or MIDI fuses and just use larger cable than needed (ie use the minimum size fuses at 30amp and match the cable to that?).