Do Solar panels also charge the starter battery

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CaliforniaCylus

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T6.1 Ocean 204
I appreciate that hooking our T6.1 to an EHU will charge both the leisure and starter battery but what happens with a solar setup

Once the leisure batteries are full does charge go to the starter battery also.

Thinking that would be useful because of the current draw of the dash cams...
 
I appreciate that hooking our T6.1 to an EHU will charge both the leisure and starter battery but what happens with a solar setup

Once the leisure batteries are full does charge go to the starter battery also.

Thinking that would be useful because of the current draw of the dash cams...
No. But it can be wired up to do that.
 
Not intentionally, however some Calis do receive a small trickle charge from the solar (to the starter) once the house batteries are full and on "float" similarly the hook up may provide a very small charge to the starter when the house batteries are on float
 
Last edited:
I appreciate that hooking our T6.1 to an EHU will charge both the leisure and starter battery but what happens with a solar setup

Once the leisure batteries are full does charge go to the starter battery also.

Thinking that would be useful because of the current draw of the dash cams...
As WG says - maybe.

My understanding of the trickle charge on EHU is it is controlled by the EHU controller which is a box of tricks that sits above the battery. That takes the power in and sends to your leisures and, like an MPPT convertor, will/can send a 1A charge to your Starter under certain conditions. It's not amazing, but enough to (hopefully) stop you getting a flat starter.

If you are using Solar you are bypassing that box of tricks, because your MPPT is connected directly to your batteries. Because there is no control from it, it (the box 'o tricks) wont send a trickle to the battery.

If you want the MPPT to do that you need an MPPT with a second battery connector (so not Victron) and then connect a wire from that all the way to the split charge relay, which is the same as essentially wiring it directly to the starter battery. Then, the same as the Cali, you get, under certain conditions, a 1A charge back to the leisures. Not enough to power a dashcam full time unfortunately. Been there, got that T-Shirt, failed. Roger did warn me.

Without this setup I'm not aware that solar just to leisures does anything at all to your starter.
 
I appreciate that hooking our T6.1 to an EHU will charge both the leisure and starter battery but what happens with a solar setup

Once the leisure batteries are full does charge go to the starter battery also.

Thinking that would be useful because of the current draw of the dash cams...
Hi,
As said previously the solar is connected directly to leisure batteries so no charge goes to the engine battery.
If it helps when I installed my solar using a Victron controller. To enable me to top the engine battery up should it ever get a bit low,
I added a break before make rotary switch as can be seen in the picture. The output of this switch goes either to the leisure or engine battery. A connection to the engine battery can be found on the split charge relay under the passenger seat on the T6(not sure if it’s the same on the 6.1)

IMG_0832.jpegI
 
Hi,
As said previously the solar is connected directly to leisure batteries so no charge goes to the engine battery.
If it helps when I installed my solar using a Victron controller. To enable me to top the engine battery up should it ever get a bit low,
I added a break before make rotary switch as can be seen in the picture. The output of this switch goes either to the leisure or engine battery. A connection to the engine battery can be found on the split charge relay under the passenger seat on the T6(not sure if it’s the same on the 6.1)

View attachment 134409I
I have often wondered about doing this actually as it seems an obvious solution. I assume the Victron unit doesn’t get confused by the sudden switch in battery capacity (ie one vs two in parallel) and charge state?
 
I have often wondered about doing this actually as it seems an obvious solution. I assume the Victron unit doesn’t get confused by the sudden switch in battery capacity (ie one vs two in parallel) and charge state?
Before switching over, I would switch the Victron off via the phone app. I probably wouldn’t need to do that as it’s a break before make switch.
To be honest I have never had the need to switch over as the 9 year old engine starter battery is still pretty healthy (beginning to wish I never said that)

If I do switch to starter, the main reason to power off for me is to change the charge profile within the app. My leisure batteries I recently changed to a big Lithium which uses a different profile to that of the lead acid starter battery.
The Victron app is a very useful and easy to use tool, to keep an eye charge rates etc. The different charge profiles for the different battery types are built in and you just need to select the one you want.
 
Hi,
As said previously the solar is connected directly to leisure batteries so no charge goes to the engine battery.
If it helps when I installed my solar using a Victron controller. To enable me to top the engine battery up should it ever get a bit low,
I added a break before make rotary switch as can be seen in the picture. The output of this switch goes either to the leisure or engine battery. A connection to the engine battery can be found on the split charge relay under the passenger seat on the T6(not sure if it’s the same on the 6.1)

View attachment 134409I

I have just reread my post here and I should have added;

It is important to remove the negative connections from ALL batteries (including the starter) before adding a wire to the engine side of the split charge relay. My apologies if this seems an obvious first step to take.
 
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