Panel voltage production VS suggested charge voltage on Ampere time battery.

[OneStudPuppy]

Ok. I am wired up and running, it’s been a long while since I used to electronics geek out. Getting back into the swing of things and reviewing everything running now a debate came into my mind.
Ampere time suggested charge voltage vs panel production. Currently panel is putting out 13.6 volts at 5 amps. Looking at the ampere time charging voltage says 14.2-14.6 under 100 amps. Now average some things are ok lower. But I’m wondering seems panel is more of a float charge capacity.
Some things are ok running lower, but now I debate in my mind will battery ever get to a truly full charge on solar alone with not matching the suggested voltage. (Like I said I’m getting back into electronics and I’ve forgotten a lot) so I’m trying to remember all the little details.

 

[rmaddy]

Post details about the exact panels and charge controller that you have.

 

[OneStudPuppy]

Post details about the exact panels and charge controller that you have.

Good point. Panel is the renogy RSP100D-BK
Renogy 10 amp controller the wanderer Renogy 10 Amp 12V/24V PWM... https://www.amazon.com/dp/B07NPDWZJ7?ref=ppx_pop_mob_ap_share


Renogy 100 Watt 12 Volt... https://www.amazon.com/dp/B096MJHMBY?ref=ppx_pop_mob_ap_share
Total wire run 10 feet from controller to plugs outside trailer. 15 foot from trailer connector to panel with a inline fuse on positive.
From controller to panel connectors 12 gauge wire and solar dedicated used.

 

[rmaddy]

Currently panel is putting out 13.6 volts at 5 amps.

Is the panel putting out those values into the PWM SCC or is the SCC put out those values to the battery?

If that's the output of the SCC then you probably need to adjust the battery charge settings of the SCC to those best suited to your battery.

 

[Bud Martin]

Good point. Panel is the renogy RSP100D-BK
Renogy 10 amp controller the wanderer Renogy 10 Amp 12V/24V PWM... https://www.amazon.com/dp/B07NPDWZJ7?ref=ppx_pop_mob_ap_share


Renogy 100 Watt 12 Volt... https://www.amazon.com/dp/B096MJHMBY?ref=ppx_pop_mob_ap_share
Total wire run 10 feet from controller to plugs outside trailer. 15 foot from trailer connector to panel with a inline fuse on positive.
From controller to panel connectors 12 gauge wire and solar dedicated used.

You have PWM SCC, so the max charging current will be around 5A since that is what the panel can produce when it is used with PWM SCC, if you want to charge at 10A you will need another panel in parallel.

 

[OneStudPuppy]

You have PWM SCC, so the max charging current will be around 5A since that is what the panel can produce when it is used with PWM SCC, if you want to charge at 10A you will need another panel in parallel.

ahh, while getting the basics of it all this is something I didn’t realize. And being a mobile set up wonder if I should have went 200 watt suitcase style panels or similar and a ppt controller..
lots to learn but the draw needs is minimal cpap primary (rated at 80 watts but I won’t be using heat / humidity features)
and lights are laughable 1/2 amp with all on. (May look at alternates brightness on the ones I have now is pretty weak).
Hands on learning sometimes I don’t realize all the differences lol

 

[camelCase]

13.6 is the float voltage, but since your lifepo4 battery has a low internal resistance, it is still able to take 5 amps of current which is still about 68w. Are you sure you have it in lithium mode? Either way, you aren't giving up all that much power. 14.6 X 5 = 73w or a difference of about 7%.

 

[OneStudPuppy]

13.6 is the float voltage, but since your lifepo4 battery has a low internal resistance, it is still able to take 5 amps of current which is still about 68w. Are you sure you have it in lithium mode? Either way, you aren't giving up all that much power. 14.6 X 5 = 73w or a difference of about 7%.

Per the menu of the controller it’s supposed to be in lithium mode. Debating this controller choice though, also the what seems to be a defect or something off when powering up the ports the low power flickering then on. Limited budget so I went with this one but realizing after the fact the renogy pre programmed lithium vs what ampere time says should be set to is a mis match but also not changeable on the controller

 

[camelCase]

Are you sure that there battery is discharged enough to go into bulk charging mode? If it's full then it won't charge at the higher voltage.

 

[OneStudPuppy]

13.6 is the float voltage, but since your lifepo4 battery has a low internal resistance, it is still able to take 5 amps of current which is still about 68w. Are you sure you have it in lithium mode? Either way, you aren't giving up all that much power. 14.6 X 5 = 73w or a difference of about 7%.

Are you sure that there battery is discharged enough to go into bulk charging mode? If it's full then it won't charge at the higher voltage.

I’d guess battery ships at 50% from Ampere time? Not sure how low it was. As of now it’s been on solar for a full day and a half or so, still talking charge wanted to let it get to what the controller reports back as a full charge before setting up a night or two in the trailer. I do need to get a battery monitor as well so I can keep a good eye on charge level.

 

[mikefitz]

The voltage at the terminals of the battery under charge will be at around 13.6 volts most of the time and only rise the target charge volts as the battery reaches full charge. The battery specification charge voltage of 14.2 to 14.6 is the end of charge volts , a target voltage.
With your battery and low charge current once the battery volts rise to over 14.0 volts consider it charged.
Any state of charge reported by your solar controller will not be accutate.
If you use the default setting for lithium the charge target voltage is 14.2, once this is reached the controller does not resume charging until the battery volts drop below 13.2.

Mike

 

[OneStudPuppy]

Appreciate all the replies, I ended up dumping the wanderer as it was defective. Now running a Rover controller 20amp. Now mppt