Maybe redundant solar winterizing question

[TWebs46]

Sorry if this has been covered but I want to be sure I've done it right. I have two, 100 amp LifePo lithium batteries in my new E19. (2022). I covered both solar panels with plywood and confirmed no incoming charge. I turned off the battery disconnect switch, flipped the two 15 amp breakers off just to be sure and removed the batteries, storing them inside.



My question: Many have said to disconnect the solar charger as well. Is this still necessary when I've taken these steps?


Thanks


Tom

[Vermilye]

As long as the panels are covered and have no output, you don't need to disconnect them. What you want to avoid is solar input to the controller without it being connected to a battery.

[TWebs46]

Originally Posted by Vermilye

As long as the panels are covered and have no output, you don't need to disconnect them. What you want to avoid is solar input to the controller without it being connected to a battery.

Thanks very much. That's what I suspected but wanted to be sure.



Tom

[alanmalk]

Originally Posted by Vermilye

As long as the panels are covered and have no output, you don't need to disconnect them. What you want to avoid is solar input to the controller without it being connected to a battery.

Perhaps I was trusting too much to luck but last year I disconnected my batteries but left the solar connected. To act as a load I left the main switch in the "on" position and a bunch of led lights in the "on" position. Had some odd flickering lighting when the sun was low but no apparent harm done.

[MarkinVan]

Isn't it when one turns off the battery disconnect switch that prevents any accessory from draining the battery?

Likewise, with the lithium battery, isn't it fine to leave connected and panel will keep battery in a state of charge via the controller and panel.

We have the Escape cover over the trailer for the winter and that seems to still allow the battery to remain in a full charge stay and seemed to work fine over last winter.

[Vermilye]

Originally Posted by MarkinVan

Isn't it when one turns off the battery disconnect switch that prevents any accessory from draining the battery?

Likewise, with the lithium battery, isn't it fine to leave connected and panel will keep battery in a state of charge via the controller and panel.

We have the Escape cover over the trailer for the winter and that seems to still allow the battery to remain in a full charge stay and seemed to work fine over last winter.

The battery disconnect disconnects the trailer loads from the battery. It does not disconnect the solar controller from the battery. If your winter temperatures do not go below 32°F, leaving lithium batteries & the solar panels connected to the solar controller is not a problem, but most lithium batteries should not be charged below 32°F. While the BMS in the batteries should prevent charging at too low a temperature, it is better not to depend on it.

The reason for disconnecting the solar panels from the controller when the batteries are removed is to prevent damage to the solar controller. Most controllers get their operating voltage from the batteries. If there is no operating voltage, input from the solar panels can damage it. You can ofter get away without a problem, but the fine print in the owner's manual often requires disconnecting the panels before disconnecting the panels, and the reverse when reconnecting.

[TWebs46]

Originally Posted by MarkinVan

Isn't it when one turns off the battery disconnect switch that prevents any accessory from draining the battery?

Likewise, with the lithium battery, isn't it fine to leave connected and panel will keep battery in a state of charge via the controller and panel.

We have the Escape cover over the trailer for the winter and that seems to still allow the battery to remain in a full charge stay and seemed to work fine over last winter.

I pulled my batteries because we’ll have plenty of sub-freezing temps over the voting winter here in St Louis. Fir lithium’s it seems to be better that way.

[alanmalk]

Originally Posted by MarkinVan

Isn't it when one turns off the battery disconnect switch that prevents any accessory from draining the battery?

I added a "total disconnect" rotary switch near the battery to remove it from all input and output. (Note! This removes power to the emergency brakes.)

Likewise, with the lithium battery, isn't it fine to leave connected and panel will keep battery in a state of charge via the controller and panel.

No. Note the "32 degree" discussion above. Plus most lithium makers suggest you should not float charge nor do a long term storage above abt. 80% charged.

We have the Escape cover over the trailer for the winter and that seems to still allow the battery to remain in a full charge stay and seemed to work fine over last winter.

Fine for all types of lead-acid.

Some notes added above...

[MarkinVan]

"(Note! This removes power to the emergency brakes.)"

Originally Posted by alanmalk

Some notes added above...

What kind of power emergency brakes do have on your Escape?

[alanmalk]

Originally Posted by MarkinVan

"(Note! This removes power to the emergency brakes.)"


What kind of power emergency brakes do have on your Escape?

The "break-a-way" switch will activate the electric brakes when the pin is pulled. It gets the power from the trailer batteries because presumably the trailer is detached from the tow vehicle. Someone else can confirm if the standard disconnect switch is not controlling the power to the emergency brake circuit?