Victron Controller Unusual Trend

[RyGuy]

Can anybody explain the trend occurring on my solar wattage? Newb here. Got it all wired up last weekend and it’s working, but this has me scratching my head. 200 ah lifepo4 battery, 200 watt panel, 30 amp controller, smart shunt, dc to dc charger.

 

[RyGuy]

Can anybody explain the trend occurring on my solar wattage? Newb here. Got it all wired up last weekend and it’s working, but this has me scratching my head. 200 ah lifepo4 battery, 200 watt panel, 30 amp controller, smart shunt, dc to dc charger. View attachment 66981

I should add it was a clear HOT day today. No clouds at all. Found it unusual that it tapered off near the time it should be peak sunlight.

 

[PaulT]

More info would be useful. The power dropping while the volts stayed high might be the battery charger entering a different phase of the charge profile. Was the SOC (State Of Charge) of the battery near full when the power dropped?

Paul

 

[RyGuy]

More info would be useful. The power dropping while the volts stayed high might be the battery charger entering a different phase of the charge profile. Was the SOC (State Of Charge) of the battery near full when the power dropped?

Paul

Hi Paul -

Great question. Looking at the trend screen comparing battery voltage/solar power it does appear there is an inverse relationship. It seems the battery “over charged” causing the controller to limit its power supply? Like I said, I am extremely green with all this. Is there any risk of damaging my battery? Should I be adjusting any settings to prevent this? Thanks for the reply!

 

[PaulT]

You may want to contact your charge controller’s tech support. They would have information on what you should see in the app & be able to evaluate your configuration settings. I’m not familiar with HQST’s products. I didn’t see a manual listed on their website. Most manufacturers want their customers to be successful using their products.

Paul

 

[pods8]

Does your battery have a Bluetooth connection to review its state of charge and internal info? It’s seems very likely your battery just got charged.

 

[RyGuy]

Does your battery have a Bluetooth connection to review its state of charge and internal info? It’s seems very likely your battery just got charged.

Hi Pod my battery doesn’t but I installed a smart shunt to be able to track that. It does appear that my battery is becoming fully charged and then it drops the controller voltage accordingly. I have lowered the input voltage on the controller. We will see if that cures my issue otherwise I will reach out to Victron. Thanks for the reply!

 

[pods8]

Hi Pod my battery doesn’t but I installed a smart shunt to be able to track that. It does appear that my battery is becoming fully charged and then it drops the controller voltage accordingly. I have lowered the input voltage on the controller. We will see if that cures my issue otherwise I will reach out to Victron. Thanks for the reply!

You shouldn't need to change the controller or contact Victron if the battery is fully charging and then solar output drops, that is exactly what happens. If nothing is consuming the wattage hypothetically available then then the controller won't produce that wattage despite being in full sun during the day, you don't need to change anything, its doing exactly what it should in that situation.

Lithium batteries have a BMS (battery management system) in them and when they are full they literally stop accepting current in, they don't "float" like a lead acid battery. Once the battery is full and turned off charging then the only thing drawing off your solar is the stuff in the camper (fridge, co/propane monitor, etc). Let me guess, you have a DC compressor fridge? Which is what likely corresponds to the wattage bouncing in the afternoon from ~0-10w to ~40-50w as it turned on and off.

You need somewhere for that 140-150w to go if you expect the panel to keep producing it vs dropping off.

 

[Vic Harder]

+1 to what others have said... your batteries are likely full and the controller is limiting charging current.