Renogy Battery Monitory - Shunt terminals are too big?!

[Dellmassive]

Yes one of those will be a chassis ground.

Most likely the big fat black one.

You can follow the cable back to see where it goes, it won't be very long, and will probably be bolted to a ground stud or bolt.

That's how the 12v system in the van works, that battery has to have a proper ground connect, as does the starter battery.

So how does that battery get charged?...

DC-dc charger?

Split charge relay?

Looks like you have EHU and a charger?

 

[RunDSG]

Yes one of those will be a chassis ground.

Most likely the big fat black one.

You can follow the cable back to see where it goes, it won't be very long, and will probably be bolted to a ground stud or bolt.

That's how the 12v system in the van works, that battery has to have a proper ground connect, as does the starter battery.

So how does that battery get charged?...

DC-dc charger?

Split charge relay?

Looks like you have EHU and a charger?

Ok. Cool. I didn’t know that. I’ll dig around.

I have a DC-DC charger, with 100W of solar as well. And a Victron charger when on hookup.

 

[Dellmassive]

nice setup.

 

[Skyliner33]

So, are you saying one of these existing neg cable is already a ground to the chassis? How do you know?

Does this photo help at all? Boxed in on the left and right. Cavity to the left is empty as far as I know, but impossible to get into. There’s a white panel which mounts on top with a couple centimetres of space underneath. Not sure where to mount busbar and shunt yet. (In front is consumer unit and battery charger, behind is some space with seat belt retractor thing on the right. Back panel is removable with magnets, not fixed.)

View attachment 143229

Ah - I can see now that hole I mentioned isnt metal. Not as bad as I thought lol.

 

[RunDSG]

or, just cut the ring ends off and use a screw down style connection.

https://amzn.to/3r2LCLn

View attachment 143188

So, I really like this option but my cable sizes are all over the place. The smallest one, I think, is smaller than 10 gauge, which is the minimum. And I’m worried the biggest will be larger than 4 gauge.

The wire I plan to run to my shunt is 25mm2, so roughly 3 gauge… so that will work in the ‘input’, but the others may not work in the ‘output’.

Am I getting this right?

 

[RunDSG]

the add any style of basbar to add all your negs too.

Amazon.co.uk : busbar

View attachment 143185View attachment 143186View attachment 143187

I’m trying to pick one of these, but they all seem to be M5 or M6, but I believe my ring terminals are all M8. Is that a problem?

The only busbars with M8 bolts are really big.

Any suggestions?

 

[Dellmassive]

this is my solar shed shunt, as an example . . M8 bolts i think.

edit - 3x M8 7 1x M6 on these busbars

Solar Sheds & Other Non-t6 Solar Projects - How We Done It -

Solar Sheds & Other Non-T6 Solar Projects - How We Done It - @Pete C requested it, so here it is . . . . . Dell, What do the batteries in your shed power ? I too have a solar powered shed - perhaps we should have a separate thread for sheds :) Pete Lets Post here any NON - T6 related ECO...

www.t6forum.com

 

[RunDSG]

@Dellmassive I think I’m going to go with this one. Very simple. I don’t have much room to mount a busbar but I should be able to make this one work. I figure I’ll connect the shunt on one side and the four previous connections on the other, and it’s not far off the existing setup.

Any reason why this wouldn’t work? Or any safety issue here?

Cam

Busbar

 

[Dellmassive]

looks ok.

like a 2way version of my one above.

 

[RunDSG]

Thanks @Dellmassive for all your help and advice on this.

I’ve got a solution I’m happy with.

Bought and fitted this small distribution block. Anchored it with a very carefully placed short screw into the plastic cover of the battery. Tbh, didn’t really require an anchor. The wires are very stiff and it wasn’t really moving. Secured the shunt down the side of the battery. Ordered two lengths of battery cable and learned that you can affordably pick these up with custom selected ring fitting sizes on the ends. Brilliant!

Then decided I still wanted to keep the functionality of the BM2 device. (Eg graph of voltage over time, check from in the house, alerts of low voltage level, etc. Things the Renogy monitor doesn’t do.)

Very happy with the outcome. Now to select a mounting position for the panel. Nervous about cutting into my cupboards!