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Why has nobody made a 3-in-one?

Dzl

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For vans, rv's and boat, 3 power sources are common (Solar, Alternator, AC). There are many 2-in-one's available to accomplish two of three tasks.

I am aware of at least 4 MPPT + B2B/alternator combos
And there are a plethora of Inverter/Charger + MPPT combo's

I wonder why no company has found it worthwhile to come out with something that combine all this functionality into one unit.
 
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Cool I had not heard of this before. I really should get around to looking into Redarc. They are one of those companies taht has been on my radar for a long time but I have never actually looked into.
 
For some stuff, it makes sense to combine functions as it saves components. For example inverters and shore power chargers can be made to share ~80% of their components.

For DC-DC charging, such as solar/PV and alternator sources there isn't a whole lot of shared components. There are however inverter/chargers with solar charge controller integrated. Though I have yet to see one which accepts sub 18V input (alternator 12V) sources.
 
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For some stuff, it makes sense to combine functions as it saves components. For example inverters and shore power chargers can be made to share ~80% of their components.

For DC-DC charging, such as solar/PV and alternator sources there isn't a whole lot of shared components. There are however inverter/chargers with solar charge controller integrated. Though I have yet to see one which accepts sub 18V input (alternator 12V) sources.
While I think you are correct (from the POV of the manufacturer) the advantage to the installer or end use is #1 convenience, potentially compactness, potentially better integration, and potentially savings in time/stress/screwups for the inexperienced builder.

Of course this comes at the cost of flexibility/modularity and potentialyl more $$

As you mention with the inverter/charger model they share a lot of components in common so its a no brainer. Victron for instance charges only ~10% more for their inverter/chargers (multiplus) compared with similar spec inverters (phoenix). But on the other hand, products like the MPP or Growatt AIO's or the Victron Easysolar are wildly popular, and these functions (MPPT + Inverter/charger) would share like 0% of their components I would think. To drive this last point home, the Victron Easysolar literally just installs a Smartsolar SCC inside the easysolar, case and all.

I hadn't realized there wasn't a lot of shared components for DC-DC + MPPT. I suppose this shows there is a market for this though since they do exist (Renogy, Kisae, Redarc, and CTEK are the companies I am aware of). So it seems natural to go just one step further and combine the functions of inverter/charger + MPPT + DC-DC. Redarc almost got there (with the product Joey linked to above, with the exception of inverter functionality)
 
I meant to say a DC-DC doesn't share a lot of components with an inverter, I should have been clearer.

But also note there are a couple different design types for PV and DC-DC controllers. For example PWM PV controllers are pretty simple, just a bank of FETs typically. The MPPT controllers are more complicated, typically converting DC to AC and back to DC. Most MPPT designs need an input voltage substantially higher than the output. DC-DC chargers for alternator charging are often required to output a higher voltage than the input. Its tough to optimize such a design, because solar panels are current limited, but have a max power point below their open circuit voltage. While an alternator is not current limited (at the rate most DCDCs operate at). So there is no need for complex logic. In addition the switching speed and behavior of the input side of a solar charger isn't always ideal for an alternator, where the loading can cause odd behavior or electrical noise.

The main reason you don't see all-in-ones as often, is due to replacement and repair costs. Lets say you upgrade your solar array, or change its voltage. Does that mean you need to replace your all-in-one ($$$$)? What about about failure, for marine applications, failure tolerance is reduced when a single point of failure exists for all these critical systems.

The other reason in my view is all-in-ones are okay at a lot of things, but rarely perfect at them. Being able to select a solar controller and DC-DC charger specifically for your usage case presents more configurability.

That doesn't mean that I wouldn't use an all-in-one if the specs and pricing were good. Especially if it reduced end user configuration, and had a convenient control/programming interface. Victron with there easy end user firmware upgrades is a great example.
 
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Alternator-Inverter-charger method works well and is cheap but isn't the most optimal. I have done a install where we used a 24v mpp all in one and used a 12v 1000w inverter from the van battery with a ignition switch remote. It ran the charger of the mpp. It also solved the issue of going to a 24v house battery without spending more money since they already had a inverter. The one major downside is the efficiency loss from going from 12v to 120 then back down to 24 for the charger...

However at least you can run smaller iso cable (extension cord) to where your system is rather then expensive large gauge welding wire. The owner I did it for has been using it for over a year without a problem last I saw. Its kind of a dummy proof charging system once you setup the mpp settings and make sure to use a inverter you can auto off and on through your ignition so I you don't forget and create a flat starter battery.
 
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