Lithium Batteries and Factory Charge Controller

[Jumbo Mug]

I installed two 200AH LifeBlue LiFePO4 batteries and the factory charger works fine. As stated does not provide the higher voltage charging profile of say a Victron Multiplus but it works. I have had Battle Borns in the past and chose the LifeBlue Low Temp batteries because in CO where I live I would have to add heat mats or somehow otherwise heat the battery area, but the LifeBlue LTs have built in heaters.

I also added 1320W of solar on the roof and replaced the GoPower charge controller with a Victron MPPT and it works great. Also rewired the 120 AC outlet near the stove so can make coffee without running the generator (wired the microwave but the inverter throws an 03 code so still working to fix that). With the new solar setup I get down to maybe 60% of the 400AH battery bank state of charge and with any sunshine it's back to 99% by afternoon. We do almost 100% dry camping so this setup works much better for us than the factory setup.

[Bob Denman]

Welcome to the Forum!
I've got a question for you about charge controllers:
My RV is pre-wired for a Go-Power controller; but I'd rather use a controller from a different source.
Are they interchangeable when you plug them in; or will I need to start clipping wires?

[DavidEM]

Bob:

I suspect the Gopower is a PWM controller and a MPPT one like the Victron will provide 15% or so more power. You should just connect the wires from the solar panels to the input and the wires to the battery to the output.

The prewiring to the panels can be 12 to 10 gauge and if you have a two or four 12V nominal panels consider wiring them in series as discussed in the article. The prewiring to the batteries should be at least 10 gauge. If you have 2-100 watt panels, there will be a voltage drop of about 0.3 volts if the batteries are within 10 feet and is 10 gauge which is marginal. Definitely increase this wire size if you have more than 200 watts of panels.

Here is a brief article on selecting and installing a solar controller attached.

David

[Bob Denman]

Thanks!

[Jumbo Mug]

Originally Posted by Bob Denman

Welcome to the Forum!
I've got a question for you about charge controllers:
My RV is pre-wired for a Go-Power controller; but I'd rather use a controller from a different source.
Are they interchangeable when you plug them in; or will I need to start clipping wires?

Hi Bob, per the docs the factory GoPower charge controller (which is PWM) is either a 10A or 30A, mine (Magnitude XG32) was a 10A, and the wiring to the panels is 10 gauge. Unscrew the GoPower from the left side of the entry (just below the closet in mine) and you will see the four wires that go to it. The solid orange and white go to the battery and the orange with black stripe and white with black stripe go to the gland on the roof and connects the solar panels via two MC4 connectors. Carefully pry up the floor to the shallow closet to gain better access to the wiring.

I mounted my Victron MPPT charge controller inside the bay that had the hydraulic unit for the jacks, on the right side (plan to weather-proof this better soon). Then extended the wires that go to the gland on the roof so they would reach the charge controller. I removed the 20A fuse inside the battery area under the steps and replaced the run from the charge controller to the batteries with beefier wiring (8 gauge thin stranded marine wire) with the positive going thru a Bussman 150A DC breaker (https://www.solar-electric.com/mrcb-...t-breaker.html) as close to the battery connection as could.

I bought everything but my LiFePO4 batteries from Northern Arizona Wind and Sun who I've bought from over the years and highly recommend (https://www.solar-electric.com/). They have experts that will help spec what you need. For the amount of solar I wanted, NAWS recommended I wire the panels in parallel and spec'ed the Victron 250/100 charge controller (https://www.solar-electric.com/victr...ontroller.html). It's pricey but will handle the high voltage from the parallel setup.

With 400AH of LiFePO4 and 1320W of solar (I bought the REC 330w panels, just over $200 per), on a day with decent sun the state of charge on the battery bank only goes down to ~65% per the built in bluetooth SoC of the LifeBlues. I also rewired some of the AC outlets to run off the Xantrex inverter so can make coffee w/o running the generator. Plan to do same with microwave as soon as figure out an issue I'm having with that. The four 33w panels are overkill but that's what I like.

PM me with your email if want me to send pics...

Mike

[DavidEM]

Mike:

Your solar installation sounds good but with one big problem and a couple of questions and some possible problems:

The problem:

The beefier 8 gauge wire you installed is only good to 80 amps and the fuse/breaker protecting it should be no bigger than that value. Also the amps from the controller can be as high as 110, so you need #4 wire to carry that much current and stay within the breaker's rating. It will also help with voltage drop which will probably be too high for best results with the
8 gauge wire.

The questions:

I am a little confused about your statement that parallel wiring of the panels increases the voltage. I think you meant series wiring increases the voltage.

In one place you say 1320 watts of panels (a huge amount btw) and in another you say 33 watts each and in another 330 watts. I am sure you meant 330 watts each. If that is correct then those are usually 24V nominal panels and their Voc the maximum voltage that they can produce is about 34. If you wired them all in series then that is 128 volts which is ok for the charge controller but requires high voltage wiring techniques which I doubt you have. I am not sure that is a real safety problem but it doesn't meet electrical codes. At the very least put some tape over the panel input connections to the controller to keep prying fingers away.

Also the maximum current output of the controller that might be expected is 1320/12=110 amps, a little more than the Victron's rating. You will only see this current when the batteries are very low requiring low voltage and high current to charge them.

I am attaching a short article about How Solar Controllers Work which covers most of these issues.

David

[Jumbo Mug]

Originally Posted by DavidEM

Mike:

Your solar installation sounds good but with one big problem and a couple of questions and some possible problems:

The problem:

The beefier 8 gauge wire you installed is only good to 80 amps and the fuse/breaker protecting it should be no bigger than that value. Also the amps from the controller can be as high as 110, so you need #4 wire to carry that much current and stay within the breaker's rating. It will also help with voltage drop which will probably be too high for best results with the
8 gauge wire.

The questions:

I am a little confused about your statement that parallel wiring of the panels increases the voltage. I think you meant series wiring increases the voltage.

In one place you say 1320 watts of panels (a huge amount btw) and in another you say 33 watts each and in another 330 watts. I am sure you meant 330 watts each. If that is correct then those are usually 24V nominal panels and their Voc the maximum voltage that they can produce is about 34. If you wired them all in series then that is 128 volts which is ok for the charge controller but requires high voltage wiring techniques which I doubt you have. I am not sure that is a real safety problem but it doesn't meet electrical codes. At the very least put some tape over the panel input connections to the controller to keep prying fingers away.

Also the maximum current output of the controller that might be expected is 1320/12=110 amps, a little more than the Victron's rating. You will only see this current when the batteries are very low requiring low voltage and high current to charge them.

I am attaching a short article about How Solar Controllers Work which covers most of these issues.

David

Hi David,

You’re right I meant series not parallel. The 330w panels are vmp 34.6v and imp 9.55a (details here: https://www.solar-electric.com/rec-s...-module.html); 33 was a typo.

I’ll look into the wiring but I’m sure 4 gauge won’t work because NAWS told me the biggest the Victron will take is 6. Just looked and the 8 gauge is rated for 600v.

I’ll call NAWS on Monday and go over the wiring and breaker but they spec’ed the breaker at 150a and also ask about the high voltage wiring to mentioned.

Thanks for the input.

Mike

[Jumbo Mug]

Originally Posted by DavidEM

Mike:

Your solar installation sounds good but with one big problem and a couple of questions and some possible problems:

The problem:

The beefier 8 gauge wire you installed is only good to 80 amps and the fuse/breaker protecting it should be no bigger than that value. Also the amps from the controller can be as high as 110, so you need #4 wire to carry that much current and stay within the breaker's rating. It will also help with voltage drop which will probably be too high for best results with the
8 gauge wire.

The questions:

I am a little confused about your statement that parallel wiring of the panels increases the voltage. I think you meant series wiring increases the voltage.

In one place you say 1320 watts of panels (a huge amount btw) and in another you say 33 watts each and in another 330 watts. I am sure you meant 330 watts each. If that is correct then those are usually 24V nominal panels and their Voc the maximum voltage that they can produce is about 34. If you wired them all in series then that is 128 volts which is ok for the charge controller but requires high voltage wiring techniques which I doubt you have. I am not sure that is a real safety problem but it doesn't meet electrical codes. At the very least put some tape over the panel input connections to the controller to keep prying fingers away.

Also the maximum current output of the controller that might be expected is 1320/12=110 amps, a little more than the Victron's rating. You will only see this current when the batteries are very low requiring low voltage and high current to charge them.

I am attaching a short article about How Solar Controllers Work which covers most of these issues.

David

Hi David,

I went ahead and called NAWS and they said you are right about #8 wire being too small, so will redo with #2 when get home.

They said the 150a breaker was correct and that the Victron is rated for up to 1450w so it’s ok too even though it says 100a.

Thanks

Mike

[DavidEM]

Originally Posted by Jumbo Mug

Hi David,

I went ahead and called NAWS and they said you are right about #8 wire being too small, so will redo with #2 when get home.

They said the 150a breaker was correct and that the Victron is rated for up to 1450w so it’s ok too even though it says 100a.

Thanks

Mike

Be careful about what people tell you. The Victron may be rated for both 100 amps and 1450 watts, WHICHEVER IS LESS. I would prefer to hear that from Victron, not a dealer. In any case you are operating on the edge.

Your 150A breaker will work fine with #2 gauge wire.

Did they say anything about the high voltage in the input wiring?

David

[Jumbo Mug]

Originally Posted by DavidEM

Be careful about what people tell you. The Victron may be rated for both 100 amps and 1450 watts, WHICHEVER IS LESS. I would prefer to hear that from Victron, not a dealer. In any case you are operating on the edge.

Your 150A breaker will work fine with #2 gauge wire.

Did they say anything about the high voltage in the input wiring?

David

They assured me it would handle my setup and I’ve used them for many builds over the years so I trust them.

They said I could put another breaker between the panels and the charge controller but I’m just going to use Bluetooth on the Victron to cut the connection if ever need to.

Mike

[The_Breeze]

Originally Posted by Jumbo Mug

I installed two 200AH LifeBlue LiFePO4 batteries and the factory charger works fine. As stated does not provide the higher voltage charging profile of say a Victron Multiplus but it works. I have had Battle Borns in the past and chose the LifeBlue Low Temp batteries because in CO where I live I would have to add heat mats or somehow otherwise heat the battery area, but the LifeBlue LTs have built in heaters.

I also added 1320W of solar on the roof and replaced the GoPower charge controller with a Victron MPPT and it works great. Also rewired the 120 AC outlet near the stove so can make coffee without running the generator (wired the microwave but the inverter throws an 03 code so still working to fix that). With the new solar setup I get down to maybe 60% of the 400AH battery bank state of charge and with any sunshine it's back to 99% by afternoon. We do almost 100% dry camping so this setup works much better for us than the factory setup.

What panels did you use to gain 1320. you don't cite your coach model, so wondering where you found the room and/or what panels you used?

Thanks.

[Jumbo Mug]

These:
https://www.solar-electric.com/rec-s...tt-module.html

Magnitude XG32. Had room for a 5th but don’t need that much. PM me your email and I’ll send you a pic.

[The_Breeze]

Originally Posted by Jumbo Mug

Hi David,

I went ahead and called NAWS and they said you are right about #8 wire being too small, so will redo with #2 when get home.

They said the 150a breaker was correct and that the Victron is rated for up to 1450w so it’s ok too even though it says 100a.

Thanks

Mike

NAWS = Northern Arizona Wind & Solar?

[Jumbo Mug]

Yes that’s them

[The_Breeze]

Originally Posted by DavidEM

Be careful about what people tell you. The Victron may be rated for both 100 amps and 1450 watts, WHICHEVER IS LESS. I would prefer to hear that from Victron, not a dealer. In any case you are operating on the edge.

Your 150A breaker will work fine with #2 gauge wire.

Did they say anything about the high voltage in the input wiring?

David

Would like to get your feedback on my setup to make sure I'm using the right stuff - particularly the wiring. Let me know where you picked up this thread and I'll try to fill in any gaps of previous info. It's ok to call things out that aren't correct or outwardly wrong.

[paulwadley]

Hi Bob
On my go power controller, the wires are mounted below the controller and are Orange Color Wire Solar +, White Color Wire Solar -, Orange Wire Battery + and White Wire Battery -. The Go Power Controller I have is a 12 volt 10 watt. I will send you a photo of it.

Paul

[Jumbo Mug]

Pic of my roof.

[The_Breeze]

This popped up in the top banner pics so including for those that want the info, including me.

[The_Breeze]

Originally Posted by Jumbo Mug

Pic of my roof.

4 panels generating 1320? What brand and type of panel please to get 330/panel?

[Jumbo Mug]

Four 330w panels = 1320w