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Which MPPT is easiest to reconfigure?

Aphers

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I'm going to be running two systems on my boat- 200w at 12v feeding a lead-acid bank, and a 600w, 32v PV array feeding the LFP.
The smaller system is primarily equipment that is only used when actually sailing, e.g. autopilot, instruments.
Once I am anchored up I may want to tap in to that extra 200w to help charge the LFP bank. I'm pretty sure I can run two charge controllers in to the same bank without any problem, so the question is, which brand/model of MPPT would be easiest to re-program?

I'm aware that this is a complicated setup with some potential for disaster. I would only be doing the swap every few weeks, not every other day.

I will also have a Sterling 30A B2B charger, which will let me send power from lead-acid side to the LFP- especially useful when using the engine. So I guess I could just use that, but it's presumably not a very efficiency way of doing it.
 
I would say Victron SmartSolar MPPT equipment.

With their app on a phone or tablet you can make changes in less than a minute.
 
Thanks both.
200w in to a 12v system, I know in theory that's about 17A, but I also know that a) the voltage will be higher, and b) the panels won't actually reach full output often if at all. So I guess 15A would be fine. In reality, if I went 10A, would I actually be losing any power? Boat would be cruising in the tropics.
 
Thanks both.
200w in to a 12v system, I know in theory that's about 17A, but I also know that a) the voltage will be higher, and b) the panels won't actually reach full output often if at all. So I guess 15A would be fine. In reality, if I went 10A, would I actually be losing any power? Boat would be cruising in the tropics.
There is almost negligible price difference (~ $10) between the Victron Smartsolar 10A and 15A, go with the 15A and you won't have to worry about your controller being a significant bottleneck.

Also, if you want to see how easy it is to use the Victron App you can download it, it has a demo mode where you can test it out with various devices before you buy.

https://external-content.duckduckgo.com/iu/?u=https%3A%2F%2Fwww.victronenergy.com%2Flive%2F_media%2Fvictronconnect%3Avc5_iphone_bluesolar_live.png&f=1&nofb=1
 
Yes it’s much cheaper to buy the bigger one to start with rather than starting smaller and having to still buy it later.

A number of us have “been there done that “ ?
 
Here is another idea (but it costs more)
Install 2 mppt’s one to each battery
Then get a switch and switch the solar power to the mppt that you want.
Then there is no issues of messing something up.
 
Another option would be to feed all the solar to your house bank, and then use a current limiting DC-DC converter or charger or something along those lines to trickle current to the starting battery (some chargers are even setup to do this out of the box, unfortunately usually they are shorepower chargers, not solar chargers)
 
Dzl. That’s a good idea and it just reminded me of a YouTube I just saw.
Beginning from this morning just put a Victron 75/15(?) mppt controller between their big 50v lithium battery (I.e. acts as solar) and their 12v starting battery. It keeps their starting battery charged. So that’s probably a better idea than switching.

wait... I was remembering the original poster had two different voltages for the batteries. If they are both 12v - this won’t work.
 
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Dzl. That’s a good idea and it just reminded me of a YouTube I just saw.
Beginning from this morning just put a Victron 75/15(?) mppt controller between their big 50v lithium battery (I.e. acts as solar) and their 12v starting battery. It keeps their starting battery charged. So that’s probably a better idea than switching.

wait... I was remembering the original poster had two different voltages for the batteries. If they are both 12v - this won’t work.
You can get a 12v to 12v dc-dc converter (like the Victron Orion) it can take an input from 10-17V and output 10-15V (adjustable, and current limiting I think)
 
Dzl. That’s a good idea and it just reminded me of a YouTube I just saw.
Beginning from this morning just put a Victron 75/15(?) mppt controller between their big 50v lithium battery (I.e. acts as solar) and their 12v starting battery. It keeps their starting battery charged. So that’s probably a better idea than switching.

wait... I was remembering the original poster had two different voltages for the batteries. If they are both 12v - this won’t work.

I was toying with running both 12v and 24v systems, but I've decided to stick with 12v throughout.
Have just been offered a good deal on a B2B so that might be the way to go, rather than reconfiguring the MPPT.
 
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