Solar Panel Causes Lower Shore Power Charging Amps

[jlhog]

I have the following installed. My camper was prewired from the factory.
When all components are connected and hooked to shore power my battery shows at 4+ amps charging.
When I disconnect the solar panel it goes to 19+ amps charging.
Renogy Wanderer Li 30A
Renogy Flexible Solar Panel 100 Watt,
WFCO WF-8735-AD Power Center
Lion Adventure BT Lithium battery

Should it be charging at the higher rate even with the solar panel connected? My son suggested putting a switch in so I can turn the solar panel off when connected to shore power, but I think it should happen automatically. What am I missing?

 

[Mark_K5LXP]

Where are you reading the indicated charge amps from?

Mark B.
Albuquerque, NM

 

[jlhog]

Where are you reading the indicated charge amps from?

Mark B.
Albuquerque, NM

The battery is Bluetooth enabled. So I read that in the app. Proabably not the most accurate, but should not be that much difference.

 

[Mr Lars]

If you unplug from shore power at night, what does the gauge indicate?

 

[Gary RV_Wizard]

The only thing I can think of is that the solar panel is producing a high enough voltage to fool the WFCO into thinking the battery is fully charged, causing it to drop back to a float charge mode (a modest constant voltage for maintaining the battery). When you eliminate the solar charging source, the WFCO detects a relatively low battery SOC and engages its bulk or absorption mode. That's something that can happen in certain combinations of solar and converter/charger battery management. Each of the chargers tries to optimize the battery amp flow without realizing that another charger is attempting the same thing.

 

[Vic Harder]

Be aware that when you disconnect the solar panel, that you do so between the panel and the Renogy Wanderer. Solar controllers don't like to be disconnected from the battery if a solar panel is still attached.

 

[jlhog]

The only thing I can think of is that the solar panel is producing a high enough voltage to fool the WFCO into thinking the battery is fully charged, causing it to drop back to a float charge mode (a modest constant voltage for maintaining the battery). When you eliminate the solar charging source, the WFCO detects a relatively low battery SOC and engages its bulk or absorption mode. That's something that can happen in certain combinations of solar and converter/charger battery management. Each of the chargers tries to optimize the battery amp flow without realizing that another charger is attempting the same thing.

I did test the panel before installing and it showed 24 volts in full sun. Would installing a switch between the panel and controller so I can turn off the solar panel when connected to shore power be an issue with anything?

 

[jlhog]

If you unplug from shore power at night, what does the gauge indicate?

I did not try that. Maybe this weekend.

 

[jlhog]

Be aware that when you disconnect the solar panel, that you do so between the panel and the Renogy Wanderer. Solar controllers don't like to be disconnected from the battery if a solar panel is still attached.

I did disconnect on the panel side. The directions for the controller said to have the battery side connected first, so I figured that was the way to disconnect the solar from the system.

 

[John From Detroit]

I did disconnect on the panel side. The directions for the controller said to have the battery side connected first, so I figured that was the way to disconnect the solar from the system.

You would be amazed at the number of folks who can't figure that out .
Or other things like that.