What is on my Valencia roof? Picture

[cmaxcliff]

There is a picture below that will correct itself when you click it. It was taken from a distance so it is not great. There are solar panels along with the Wineguard, skylight, fan, and 2 AC units.

My question is, is that a solar panel next to the rear AC unit? Since it is by itself I almost thought it was Starlink. Why would there be so much distance between it and the other solar panels?

Also, is that the standard amount of panels for a 2022 Valencia 38RW?

I just bought this and I have a bad house battery to replace as well as a BIM that allows the house power usage to draw on the chassis battery.

We mostly use the RV without hookups at race tracks and our 2010 Newmar Class A did not rely on solar so I need to get up to speed on the solar capabilities to try to be conservative with the generator.


https://www.irv2.com/forums/attachme...1&d=1744671201

[oldenavy]

Looks like another solar panel. Hard to tell from the picture, too far away and not high enough.

Factory solar system on our LE is three panels of 175 or 200 watts each (I forget which), wired in parallel. Controller is a Victron 100V/50A.

What is the ratings on your solar controller? Your solar may be limited by the panels or the controller, it depends on the details.

[Dan-Dekalb]

Looks like it. A lot of times Solar just gets put wherever it fits. There could be something below that prevented all the panels up next to each other. With respect to boondocking, three panels won't take you very far. If you already have a bad house battery, look into replacing it with a pair of big Lithium batteries. Epoch 460's are a good option. Three 200W panels in the real world are only going to produce an average of 300W over a 8 hour period, or 2.4KWh. My refrigerator pulls about 2KWh per day, so 400Wh of power is all that's available for other loads.


We've added solar panels to our Classic, we're up to almost 2KW. I put in 4 300AH Epoch lithium batteries for a total of 1200AH. We can boondock pretty much until we run out of water or have to dump tanks. With relatively mild temperatures, we can even run our back AC with the door closed off of the batteries over night. We did upgrade to dual inverters and the whole RV is run off of the inverters. In your situation, the best bet would be to run the generator towards the end of the day to top off the batteries for overnight. That way you capture as much solar as you can during the day, but don't have to run the generator all the time. Adding more panels just reduces the amount of generator run time.


Best of luck


Dan

[d23haynes57]

"I just bought this and I have a bad house battery to replace as well as a BIM that allows the house power usage to draw on the chassis battery."

If the "Battery Interface Module" is a dual direction voltage controlled set up, (is it?) the combination of fully charged Lithium, (resting voltage 13.6) and the solar will keep the voltage high enough that the battery banks will remain connected. This is due to Lithium being so close to alternator voltage. Most voltage sensing BIMS will maintain the connection until the voltage drops somewhere below 13 volts. If the chassis bank is lead acid this may be as low as 12.6 volts. There are some advantages to this approach. If you want to disable this you will need to add some other control. Having Lithium House and AGM chassis batteries makes this work out really well. Lead Acid and AGM both loose the top 10% or so of charge quickly so this lets those batteries provide some power to use that until the battery voltage drops. In reality, with fully charged Lithium this continues to float, top off the chassis batteries even after the charging source stops.
To get better control my charge controller is the Blue Sea 7622.

https://www.bluesea.com/products/762..._-_12V_DC_500A

Ultimate manual and automatic control with a large indicator light.
And probably the highest capacity, bullet proof "BIM" out there.

[cmaxcliff]

Thank you for the comments/advice.

Sometimes we are able to get a hookup while we are racing which is very nice. That was with our older MH. Otherwise we generally run the generator when using AC because having the windows open is loud with race engines. At night we open windows unless it is very hot.

I have a new BIM coming and will be getting a new 330ah AGM battery. The bad battery is 245ah and it also pulls the chassis battery down as it depletes. I am still uncertain what ah battery was in the rig when new. Renegade is vague but they quoted $2600 for a 330ah AGM, yikes!

There are so many brands of batteries I am not sure which is a quality AGM brand. Opinions?

At the race track we can run the generator without noise being a problem and I doubt we will boondock in a quiet area next to other campers.

[d23haynes57]

300 A/H Lithium batteries are running around $600.
That is now the sweet spot for cost per A/H.

[Dan-Dekalb]

Originally Posted by cmaxcliff

Thank you for the comments/advice.

Sometimes we are able to get a hookup while we are racing which is very nice. That was with our older MH. Otherwise we generally run the generator when using AC because having the windows open is loud with race engines. At night we open windows unless it is very hot.

I have a new BIM coming and will be getting a new 330ah AGM battery. The bad battery is 245ah and it also pulls the chassis battery down as it depletes. I am still uncertain what ah battery was in the rig when new. Renegade is vague but they quoted $2600 for a 330ah AGM, yikes!

There are so many brands of batteries I am not sure which is a quality AGM brand. Opinions?

At the race track we can run the generator without noise being a problem and I doubt we will boondock in a quiet area next to other campers.

Just remember, with AGM, you can really only use 50% of the capacity without drastically shortening the life of the battery. It sounds like Renegade quoted you Lithium at that price. Epoch has a 300Ah with Victron communication for $1,500. (https://www.epochbatteries.com/produ...y-dual-purpose)


This is the drop-in replacement for the BIM that Renegade usually ships. https://www.amazon.com/Battle-Born-Batteries-Lithium-Isolation/dp/B07DY8S815/. An AGM is usually good for about 600 discharge cycles before the capacity drops significantly. That will translate to replacement every 2-3 years in your use case. Lithium is rated for 6,000+ cycles with 80% retention of capacity. Epoch offers an 11 year warranty on their batteries. Long term, when you consider cost and lifetime, Lithium is less expensive.

[cmaxcliff]

This has been helpful for the uneducated me.

1- If an AGM can safely go to 50% before a charge than how low can a lithium battery go? A 330ah AGM delivers 165ah and then needs a charge? If I bought a 460ah Epoch lithium how much ah can I use before charging?

2- Precision Circuits has a special lithium BIM that bolts right in exactly like the original AGM one. What is the difference in function?

3- When asking the Renegade tech department what modifications are needed to install a lithium battery. They said none. That can't be right, right?

4- Does a larger ah battery take proportionally longer to charge due to the greater amount of ah depleted or does the larger amount of storage area give greater speed to the charging?

I don't really want to do any rewiring or other modifications but changing the battery and the BIM seems easy unless I am missing something important. I know that just doing that won't make a big boondocking improvement but it has to help a little.

[MemByTheMile]

Originally Posted by cmaxcliff

This has been helpful for the uneducated me.

1- If an AGM can safely go to 50% before a charge than how low can a lithium battery go? A 330ah AGM delivers 165ah and then needs a charge? If I bought a 460ah Epoch lithium how much ah can I use before charging?

2- Precision Circuits has a special lithium BIM that bolts right in exactly like the original AGM one. What is the difference in function?

3- When asking the Renegade tech department what modifications are needed to install a lithium battery. They said none. That can't be right, right?

4- Does a larger ah battery take proportionally longer to charge due to the greater amount of ah depleted or does the larger amount of storage area give greater speed to the charging?

I don't really want to do any rewiring or other modifications but changing the battery and the BIM seems easy unless I am missing something important. I know that just doing that won't make a big boondocking improvement but it has to help a little.

1) I don’t know the epoch BMS, but most lithium iron phosphate battery systems allow you to go down around 5 to 15% of ah capacity before the BMS shuts it down to protect it self.

2) Key functional difference in the lithium BIM is it does not allow full uninhibited charging of the lithium battery from tht vehicle charger - it does not dial it down but has a timer type function that allows charging for (IIRC) roughly 15 min then opens the circuit to give the alternator a break for 15 min, then closes the circuit to allow charging… Many don’t like this approach but instead opt for a DC to DC charger that has a lower amp rating, putting a lower amp draw on the alternator.

3) The other technical changes that need to be considered; adjusting the converter/charger function to charge the house batteries correctly when on shore power or generator power, and you might want to check cabling to be sure proper gauges were used to handle the lithium amp draw that is possible. Should also consider ensuring you have battery disconnect switches on the lithium batteries for safety purposes that are right by the compartment door for easy reach.

4) Charging time - this will vary. Lithium can take a charge faster than AGM or lead acid, but if your charger isn’t putting out higher amp and if you are putting in a much larger battery, then you can plan on longer charge cycles. All depends on how many watts you are pumping back in and what are the limits of your charger (and cabling).

[SafariBen]

1. AGM or flooded lead acid can go a lot deeper than 50% without dramatically affecting the lifetime Watt Hour output. Li has a very similar life vs depth of discharge curve, just far more cycles at every point in the curve.



When Li goes "0-100%" that is what the BMS allows you "for public consumption" if you will, and is usually extremely close to rated. If one cell reached true 0% it would be instantly ruined, so BMS is mandatory. While lead is protected by a low voltage cut off in most inverters, they are not usually protected from DC loads.

[Dan-Dekalb]

Originally Posted by cmaxcliff

This has been helpful for the uneducated me.

1- If an AGM can safely go to 50% before a charge than how low can a lithium battery go? A 330ah AGM delivers 165ah and then needs a charge? If I bought a 460ah Epoch lithium how much ah can I use before charging?

2- Precision Circuits has a special lithium BIM that bolts right in exactly like the original AGM one. What is the difference in function?

3- When asking the Renegade tech department what modifications are needed to install a lithium battery. They said none. That can't be right, right?

4- Does a larger ah battery take proportionally longer to charge due to the greater amount of ah depleted or does the larger amount of storage area give greater speed to the charging?

I don't really want to do any rewiring or other modifications but changing the battery and the BIM seems easy unless I am missing something important. I know that just doing that won't make a big boondocking improvement but it has to help a little.

As MemByTheMile mentioned, the LiBIM uses timing to reduce load on the alternator. I'm fortunate, in my Classic, I have a 270A alternator. I usually see charge coming in around 175A to my batteries just from the alternator. On a smaller size alternator, it is likely to overheat and cause early failure, especially if you're just idling and not running the RPM's up to help cool it. The LiBIM turning off and on allows the alternator to cool.


I usually try to not go below 80% depth of discharge (20% remaining power) and the BMS will cut out around 7% left. Because the internal resistance of a lithium battery is much lower than an AGM, they will accept a much higher charging current. An AGM will bulk charge relatively quickly to 80%, but then take about the same amount to "absorption" charge to ~95%, then about the same amount of time to float to 100%. Ideally in your situation with solar, you'd use the generator to bulk charge, then turn it off and let the solar do the absorption and float portions. In comparison, the Victron Multiplus will put out 120A of charging current. Let's assume over night you've drawn the 300AH down to 25%. You have to put 225AH back into the battery bank. At 120A from the charger, you're basically running the generator just under two hours a day. That translates to about a gallon of fuel per day and quiet nights.


After swapping out the BIM, the only other significant change is the charge profile. The 300AH specifies a charge voltage of 14.2V. Another nice part of that battery is you can run a Cat5 cable from the battery to the Cerbo and it will communicate with the Victron and show the battery status in your display. You can use what's called DVCC to let the battery dictate charge rates, etc. It's not a necessary item, but nice information to have.


Hope this helps.


Dan

[Bayouownbeer]

There are three solar panels. And just have to change the BIM and change the inverter settings to lithium. Also change your settings on the solar controller.

[cmaxcliff]

The comments here have been very helpful and I am slowly getting comfortable with a plan of attack. Thank you.