B2B Charger -VE Out...To Where?

[1Pearman]

Hi ,
I've just finishing up wiring in my Renogy B2B charger. It has a -VE out which i'm planning on taking to the negative on the leisure battery. Is this OK or does it need to go to chassis earth? The Renogy wiring diagram does not specify and just connects it into the -VE 'circuit'. Hoping the -VE on the leisure battery is OK as the cable run is much shorter than taking it to chassis earth.
Thanks

 

[Skyliner33]

Is there any battery monitoring on the leisure battery?

Or is the leisure battery connected directly to a chassis earth, or via a bus bar?

More information and perhaps pictures would be helpful.

 

[Loz]

It all depends on whether you have a shunt connected to the battery for monitoring. If you do then it's chassis, if not direct to battery negative or negative busbar.

 

[1Pearman]

Ok thanks guys, I’ve got battery monitoring via the B2B charger. It has a Bluetooth connection to app that will give me leisure battery status.
set up is van battery to b2b and solar to b2b. Then +ve out to leisure battery, and +ve cable to second leisure battery from first. The two leisure batteries are connected together at -ve and then the second one to chassis earth (batteries in parallel balanced method).
I've then got leisure battery +ve to fuse box and fuse box -ve back to chassis earth

 

[Dellmassive]

as above.

it can go to either . . . . provided its also connected to chassis ground.

ie: DC-DC -VE to Battery NEG post >then battery NEG post to Chassis GOUND.

the 20/40A Renogy DC-DC (blue unit) has TWO grounds - both need to be chassis ground -0v.

the 30A/50A DC-DC + MPPT (black) has only ONE ground.

blue unit below.

 

[1Pearman]

Spot on. Thanks for confirmation @Dellmassive
I’ve got a 2 battery set up under the passenger double bench. I’ll add some info and images to your thread on that very subject when I’m done.