Please eval my wiring diagram

[Mooncarter]

Right you are JohnnieB. My bad. I see it now.

[Goliath]

Thanks Johnnie. I'm gonna go back and clean up the diagram tonight. I actually already ordered another Blue Sea Systems 6 circuit fuse panel, with neg bus.

I've never worked with 48v as a supply voltage, and just saw that this fuse block is rated to 32v.

For this specific application, do you really think it's an issue? I'm basically using it for relay power distribution, to keep the number of connections on the battery to a minimum. I want to keep the main batt feeds with as much surface area as possible, as these lithium cells only use 1/4" bolts. I'd also like to keep it as clean as possible.

The only high current 48v application is the converter, which I could hook to the batt, but would prefer to use the fuse block as well.

I didn't consider the flash-over scenario with 48v.
If you think it's a problem, I can change it. The converter does have and inline 20A fuse, so if there was a problem, it would pop. I could add 3 inline glass fuses to the relays.

Interestingly, the converter uses an automotive blade fuse on the 48v main.

[JohnnieB]

How long are the main 1/4" studs on the Li batteries? Long enough for a thin nut to tighten down the high current cable to the drive system, then have room the lighter gauge wire to the 48V fuse block and nut on top of the first nut?

Some automotive type blade fuses have a 58V rating. Here's a link to Littelfuse: http://www.littelfuse.com/products/f...ade-fuses.aspx

[Goliath]

They're pretty short, but I think they're long enough for 1 eyelet on top of the 1 gauge cable end.

I bought a few FTZ 1/4" power lugs specifically for this.

Here's 3 pics of the bolt going into one of the cells.

https://drive.google.com/drive/folde...AP?usp=sharing

BTW, I've tried to insert pics from my Google Drive using shareable links. I've tried sharing a link to the pic itself, and the folder, but the post shows up blank. Any suggestion for getting the actual pic in the post? I know it's a basic question, but I've been messing around with it in the "Test Posting" section, and can't seem to get it to work.

[JohnnieB]

Looks like you've got what you need to connect the 48V fuse block wire on top of the high current cables.

I use a desktop computer, so I just copy the pictures from my HDD into the attachment manager. (paperclip icon)

[Goliath]

I was trying to make it harder than it was (adding pics). On a deep sea fishing forum I go to, it's a more convoluted process...

I figured another (better) solution.
I'm just going to take the 48v B+ and B- from the controller, as it has larger bolts anyway.

[JohnnieB]

Originally Posted by Goliath

I was trying to make it harder than it was (adding pics). On a deep sea fishing forum I go to, it's a more convoluted process...

I figured another (better) solution.
I'm just going to take the 48v B+ and B- from the controller, as it has larger bolts anyway.

The controller's B+ terminal only has B+ on it when solenoid is energized. (If there is a pre-charge resistor on the solenoid's large terminal, B+ less a few volts will be present, but won't be a good source for the 12V reducer because it is passing through a 470Ω resistor.) Pick up B+ on the battery side solenoid terminal.

[Goliath]

Must have been tired when I posted that.
Just looked and had it in my notes to avoid that, as it's switched power.

Thanks!

[Goliath]

Hopefully final version.

The only major change is I rerouted the B+ main feed to the 48v fuse box to be switched.

The previous version had the fuse box always live, so the headlamp relay could be left on if the key was shut off with the headlamps on, causing a parasitic draw.

@JohnnieB - Thanks for the link to the higher voltage fuses. Knowing the options available make the job much easier, which is a primary reason boards like this exist!

[sformal]

Just a remark, I did not want to jump on it, but I would use more relays, like with your light bar, etc...

If today, you plan something like 3 to 5 amps, there are plenty of bars 10+ amps, and it would be nothing to add today and really a pain in the a*** later; less than 1$ a Bosh relay (at least here). Just my 2 cents...