Charge controllers

[Shiny16]

I know there are many threads on this topic but I cannot seem to find exactly the info I’m looking for.
I have the Airstream supplied Explorer 2. It starts to charge at about 12.6 volts on the display. It never charges to 100 percent. So if you use just a bit of power all day sometimes it won’t hit the trigger for charging until the sun starts to set. In either case you start the evening off at about 85 percent at least according to the display. Will a mppt controller Bring it to 100 percent?

[BayouBiker]

Yes a controller with a better profile such as MPPT will optimize available solar output and to the extent it is sufficient, it will bring the battery bank to 100% and keep it there.

[gator.bigfoot]

Originally Posted by Shiny16

I know there are many threads on this topic but I cannot seem to find exactly the info I’m looking for.
I have the Airstream supplied Explorer 2. It starts to charge at about 12.6 volts on the display. It never charges to 100 percent. So if you use just a bit of power all day sometimes it won’t hit the trigger for charging until the sun starts to set. In either case you start the evening off at about 85 percent at least according to the display. Will a mppt controller Bring it to 100 percent?

Yes and no. Any good charge controller can bring it 100%. But it depends on the state of your batteries the wiring and your solar system. If don't have enough solar you may be using more than you can make. If your batteries aren't working properly then no amount of charging will bring it to 100%. If your wires aren't sized right for the application then you've wasted your money. MPPT is good, but it doesn't work miracles. With a small solar system you probably won't even see the difference. There are many things that make an efficient system and the charge controller is just part if that equation. It's not the end all and be all.

You'd be better served finding out what your current charge controller is putting out, what you are using and measuring the state of your storage system. Start with a good quality battery monitor and go from there.

[Shiny16]

You can force the controller into charge mode and it will go to 100 percent at least as far as the display is concerned. I understand that does not tell the whole story absent a battery monitor but 100% On the display is certainly mo better then 85% on the display.
Additionally I have two lifeline AGM batteries and 180 watts of solar. It’s enough for my needs. Getting it to 100 percent before sunset leaves some wiggle room.

[Shiny16]

I’m confused here. On my last trailer I installed a system from scratch. This has me confused about swapping the controller for a Victron. There are 8 gauge wires that I don’t think will fit a Victron. I’m also confused about which wire is which.

[ROBERT CROSS]

Do I read 'solar' upside down, on the white tag on the yellow wire?

Bob
🇺🇸

[AirMiles]

Originally Posted by Shiny16

I’m confused here. On my last trailer I installed a system from scratch. This has me confused about swapping the controller for a Victron. There are 8 gauge wires that I don’t think will fit a Victron. I’m also confused about which wire is which.

8 gauge will fit into a Victron 100/30 or 100/50. The yellow wire marked solar is your positive, there is a 8 gauge green wire that is probably connected directly to your negative busbar which is negative. Those two wires get connected directly into your Victron solar controller. These Victron controllers have 6 gauge connections which are thicker than 8 gauge wire. I would suggest increasing the size of the output wires from the Victron solar controller to the busbars ( the red and black wires in your photo). I used 6 gauge wires between the solar controller and the busbars and a breaker that was one size larger than the maximum output of the Victron solar controller (40A breaker for a 100/30 and 60A breaker for a 100/50).

A Victron controller will start charging when the solar panels provide 5 volts more than battery voltage and will keep charging until the input voltage is 1 volt above battery voltage. It will drop to float charging voltage when the batteries get 100% charged. If you configure solar panel pairs in series-parallel, battery voltage plus 5V will happen early in the morning (at sunrise or possibly first light). An MPPT solar controller is required to configure in series-parallel. MPPT controllers are most efficient when operating at higher voltages from larger panels or when smaller panels (100W) are connected in series-parallel. This is all covered in the Victron operations manual.

[KK4YZ]

Originally Posted by Shiny16

You can force the controller into charge mode and it will go to 100 percent at least as far as the display is concerned. I understand that does not tell the whole story absent a battery monitor but 100% On the display is certainly mo better then 85% on the display.
Additionally I have two lifeline AGM batteries and 180 watts of solar. It’s enough for my needs. Getting it to 100 percent before sunset leaves some wiggle room.

Ok, I’ll bite. How do you force the standard controller into charge mode? I have the same factory setup you do.

Thanks,

Jim

[BayouBiker]

Yellow is the positive side of the solar panel array (8AWG may be overkill....). Red goes to the + battery bus, black to the - battery bus. the negative solar array goes directly to the bus or chassis.

Edit: Okay Im late with this, please disregard. What they said ^

[BayouBiker]

Originally Posted by KK4YZ

Ok, I’ll bite. How do you force the standard controller into charge mode? I have the same factory setup you do.

Thanks,

Jim

Looking at the features descriptions on the Atkinson website they say there is a way to do it from the remote panel.... Honestly I'm losing interest so I didn't try to find the manual. good luck.

[Shiny16]

Originally Posted by ROBERT CROSS

Do I read 'solar' upside down, on the white tag on the yellow wire?

Bob
🇺🇸

I knew that is solar. I just could remember if it was neg or pos.

[Shiny16]

Originally Posted by BayouBiker

Yellow is the positive side of the solar panel array (8AWG may be overkill....). Red goes to the + battery bus, black to the - battery bus. the negative solar array goes directly to the bus or chassis.

Edit: Okay Im late with this, please disregard. What they said ^

Thanks for this and your other post. It make a bit more sense now. I’ll take a few days and mull it over.
I had a smaller Victron on my previous trailer which no way would except 8 gauge. I’ll look at the 30.

Thanks again!

[Shiny16]

Originally Posted by KK4YZ

Ok, I’ll bite. How do you force the standard controller into charge mode? I have the same factory setup you do.

Thanks,

Jim

Just select charge then hold the button in for a few seconds.

[KK4YZ]

Originally Posted by Shiny16

Just select charge then hold the button in for a few seconds.

Thanks
👍

[gator.bigfoot]

Those controllers leave something to be desired. But I still left mine in place even after installing another controller. I makes a great volt meter and if left "live" you won't have a readout on the wall of the trailer that is "dead". I just removed the solar wire and wired it to the new controller and ran smaller wire for the positive. In any case you'd be well served to upgrade the charger for the couple hundred bucks it takes.

Victron charge controllers will also work in PWM if the solar input isn't high enough giving you the best of both worlds. So I wouldn't worry about the panel input voltage too much. For small systems like yours and mine PWM will work fine. If you have a much larger system then MPPT makes more sense, but for the difference in money now a days it's almost a wash. Just make sure you don't shade your panels too much in your pair configuration if you go series parallel or you will drastically drop your output. The more pairs you have of course it will better your odds. But with your current 2 panels I would stay in the Parallel configuration you currently have.