24v to 12v converter in 24v system.

[crccrkc1995]

I need 24v to 12v converter for my shuttle bus conversion. I have 800w solar, 2 SOK 12.8v batteries that I'm putting in series, 2000w 24v inverter charger, 50amp mppt a Victron 1000 DC Lynx Distributor and a 110 and 12v distribution box.
I've been following plans from others and learning as much as possible but want to make sure I get these connections correct. I have a 40A converter
Can anyone tell me the correct location and connections for this? Thank you!

 

[HRTKD]

I would hazard a guess that your 24v-12v DC-DC converter would hang off of the Linx Distributor.

 

[chrisski]

I’d not use the lynx distributor and use a separate busbar, fused of course with the main input and all output also fused.

So this kind of bugs me about the lynx distributor which uses mega fuses. A google search shows the smallest they come in is a 100 amps, so ensure your wire is rated for that. My favorite ampacity chart shows 100 amps to be 4 AWG, but the same chart shows 40 amps to be 8 AWG. Use your own favorite ampacity chart, but better is to see the manufacture spec of the wire you’re using.

That leads to other things like, if you are fusing to protect 100 amps, will the DC converter take a 4 AWG or thicker wire? In my solar build when I oversized for voltage loss with wire, I found it was too thick to insert into a piece of equipment. I found at a lot of equipment that was 30 amp rated could not take thicker than a 10 AWG wire.

I may be getting the lynx distributor wrong, but to me if it uses mega fuses, makes installing a leg with a fuse of less than 100 amps difficult. Seems to me you only want to fuse 100 amps and above through a lynx distributor. For my build, the only item in excess of 100 amps is my inverter, but those tend to list Class T fuses as requirements in the owners manual.

 

[Dantheman]

i may be facing a similar step down requirement, what 24v-12v converter did you use for your builds?