Battery Charge Prioritization with 2 Solar Units and Controllers?

johnfconway

Wanted to test wiring for Renogy 200W Suitcase installation completed yesterday. Today is muted sunshine and windy. Because of the wind, I did not try to cover up rooftop panels, so both panel sources are sending power to respective controllers, both Victron SmartSolar 75/15s. Thankfully I must have gotten the wiring and fusing right!

Light on the rooftop controller is green. On suitcase it's amber. I turned on refrigerator to create some draw. Rooftop is on float. Suitcase is on absorption. I've read that with more than one controller they kind of work together. I doubt the suitcase controller told the rooftop controller to take the day off. Is it random or could the controller receiving the most power becomes the one adding charge?

Sharon_is_SAM

Which controllers - Victron?  Renogy?

johnfconway

Victron 75/15s

Denny16

From what I have prevread, when the two Victron controllers are networked together, they set the best charging situation.  If the portable panels are generating enough power to provide the required charge level, based on battery charge status, that solar panel set, will charge, whist the other one is set to idle.   If the battery charge is low enough, both sets of panels can start changing the battery/batteries.  It is very situational, depending on the sun, and the battery state of charge.  I haven’t had both the roof and portable panels in sun at the same time with a low charge battery, to test this.  

Cheers 

Grumpy_G

I suspect you're seeing the effect of the two charge controllers being at different times in the charge curve. The roof controller has been powered on for some time and reached float state. The suitcase controller starts its cycle when you plug it in, then it sees the voltage being high enough to go into absorption. After whatever time is programmed into the controller it will also reach float. 

pthomas745

What do the flashing lights mean?  (I would confirm this with what the manual says.)

https://www.pysystems.ca/resources/boating-tech-talk/what-do-the-flashing-lights-mean-on-my-victron-75-15-mppt-solar-controller/

This is the manual's page, but I don't know how they might react in a "networked" situation.

https://www.victronenergy.com/media/pg/Manual_BlueSolar_MPPT_75-10_up_to_100-20/en/monitoring.html#UUID-25a585c6-9f5a-0ece-be2b-f72769bcc5cd

johnfconway

I put everything away, so next observation will be at campsite. I had forgotten to add the suitcase controller to the network. It's in there now. I think we're good!

subkron

Once you create the network in the app and add both controllers you will be able to see the individual contribution and total network solar energy.

johnfconway

subkron said:

Once you create the network in the app and add both controllers you will be able to see the individual contribution and total network solar energy.

Looking forward to parking trailer in shade, setting suitcase panels at least part of day in sun, keeping cabin temperature below 85 degrees during the day and letting the Isotherm 2-way fridge keep the food safe. Enough of a dork that I'll be calling up the bluetooth and watching panel activity. When parked in what looked like heavy shade on past trips, sunlight almost always got through to the roof panel.