Inverter Solar Battery upgrades to 22MLE

[howson]

My intention/ plan is to seperate the leveling jacks and associated controls from the new batteries, basically leave them untouched.

Can you elaborate on why you're planning on wiring your new system in this manner? (I'm also curious!)

Howard

[jackbefus]

Jack,
We have joined the GD family last yea (2023) in October with a 278BH.
Perviously, we had converted a skoolie.
On the skoolie project, I had 1800W solar on the roof, 2-400amph batteries.
The only time we ever ran the batteries down were on the beach in TX at night.
Once the su came up, we had full batteries within a few hours.

On the new rig, I am in the initial stages of adding roughly he same set up to the 5th wheel.
The plan will be 1800w, adding an additional 400 amphrs to the battery bank( we have 2 roof ac units and I would have more than not enough to keep everyone cool), the Multiplus II (capable of 50 amp service aka 2X120V).
The one question that I did not see answered is relating to the OEM 12v system.
My intention/ plan is to seperate the leveling jacks and associated controls from the new batteries, basically leave them untouched.
Have you addressed that concept?
Just curious.

Thanks for the question, Mr. Curious :--) -- I am working with a GD 22MLE, which is a 'couples trailer, or couples camper', 26 ft long overall. I don't have those systems, so I'm not familiar with how they work or how you would integrate their power into this sort of system.

Thanks,

Jack

[jackbefus]

One more question to anyone with an opinion: what is the prevailing wisdom regarding 48 volt Battery/inverter systems vs 12 volt. I understand there are some tradeoffs, but would be interested in any comments.

[Country Campers]

One more question to anyone with an opinion: what is the prevailing wisdom regarding 48 volt Battery/inverter systems vs 12 volt. I understand there are some tradeoffs, but would be interested in any comments.

My only comment would be that you will need to convert down to 12 v dc, another part for the puzzle.

Brian

[howson]

One more question to anyone with an opinion: what is the prevailing wisdom regarding 48 volt Battery/inverter systems vs 12 volt. I understand there are some tradeoffs, but would be interested in any comments.

In brief, it complicates the accessories used in conjunction with a solar setup since the MPPT operating voltage and the open voltage of the panels will (by necessity) be much higher than 48V. Any component between the panels and the input of the MPPT will have to have a voltage rating that can handle the highest potential from the panels.

Most individuals have found that a 24V system is a good compromise to allow for smaller wires but yet have a maximum voltage within the range of the accessories commonly used.

acoleman43 (Allen's) thread may be informative: https://gdrvowners.com/forum/solar/8...l-momentum-21g

Bottom line: IMHO for most owners a 12v system is a good option. 24v and 48v are for advanced user/installers with specific system requirements.

Howard

[acoleman43]

One more question to anyone with an opinion: what is the prevailing wisdom regarding 48 volt Battery/inverter systems vs 12 volt. I understand there are some tradeoffs, but would be interested in any comments.

I have a 24V system. The advantages, in my opinion, of 24v over 12v are: More efficient, smaller wire sizes. Basically, if you have a "larger" system (10KWH+ battery bank, 1600W+ solar array) a 24v system might be worth it.

But, be warned, there are some disadvantages. You will need to convert 24v to 12v for your 12v system. If you have large 12v loads (basically over about 70 amps), the DC-DC converter (24v to 12v) becomes very large, expensive, hot and inefficient. If you have an onboard generator, the starter is 12v. You will not have a big enough converter for this and will either have to carry a 12v battery just to start your generator, or pay almost $1000 to replace the 12v starter with a 24v starter.

A 48v system exaggerates the issues (and advantages) of a 24v system. It is very difficult finding 48v to 12v DC-DC converters. With a 48v system, you will probably do best having 2 DC systems...one 48v system (with your 48v battery bank for the main 48v inverter for your AC/120v system) and a 12v system for your 12v DC side. You would likely want to set up a charger in your main AC panel to charge your 12v batteries/system.

Anyway, it is always easier going with a 12v system. Much less complicated.

[jackbefus]

I have a 24V system. The advantages, in my opinion, of 24v over 12v are: More efficient, smaller wire sizes. Basically, if you have a "larger" system (10KWH+ battery bank, 1600W+ solar array) a 24v system might be worth it.

But, be warned, there are some disadvantages. You will need to convert 24v to 12v for your 12v system. If you have large 12v loads (basically over about 70 amps), the DC-DC converter (24v to 12v) becomes very large, expensive, hot and inefficient. If you have an onboard generator, the starter is 12v. You will not have a big enough converter for this and will either have to carry a 12v battery just to start your generator, or pay almost $1000 to replace the 12v starter with a 24v starter.

A 48v system exaggerates the issues (and advantages) of a 24v system. It is very difficult finding 48v to 12v DC-DC converters. With a 48v system, you will probably do best having 2 DC systems...one 48v system (with your 48v battery bank for the main 48v inverter for your AC/120v system) and a 12v system for your 12v DC side. You would likely want to set up a charger in your main AC panel to charge your 12v batteries/system.

Anyway, it is always easier going with a 12v system. Much less complicated.

Greatly appreciate your counsel, Brian, Howard and Allen. Will stick with 12v.
Jack