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recommend a good 48v mppt switching charger

Prof Chill

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Apr 11, 2022
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Hi - I'm setting up a solar system on a boat with a 280ah 48v battery made up of eve cells. I'll have two 435w panels putting out about 80v each, running in parallel. I'm trying to decide if it would be better to run an all-in-one inverter charger, like the growatt or MPP, or if I'd be better off with individual charging and inverting components. One of the things that's pushing me away from the all-in-one is the heavy idle watt consumption on these boxes. What I'm wondering is if there is a good charger that can use both shore power or solar, and can automatically switch from one to the other. Any thoughts?

Thanks-
 
Victron is used a lot in the marine industry and have what you are looking for. Their inverters are also much lower idle current (they specify no load usage directly on their spec sheets).
 
What I'm wondering is if there is a good charger that can use both shore power or solar, and can automatically switch from one to the other.
That is an all-in-one (inverter, charger, transfer switch, solar charge controller).

Keep in mind that there's no need to automatically switch between shore power and solar. You can use both at the same time.

Having an inverter/charger (which will include a transfer switch) and a separate solar charge controller is basically the same as an all-in-one. But it has the advantages of buying separate components that both meet your exact needs and will typically have lower idle usage. It's just slightly more involved due to extra wiring and fuses over an all-in-one.
 
That is an all-in-one (inverter, charger, transfer switch, solar charge controller).

Keep in mind that there's no need to automatically switch between shore power and solar. You can use both at the same time.

Having an inverter/charger (which will include a transfer switch) and a separate solar charge controller is basically the same as an all-in-one. But it has the advantages of buying separate components that both meet your exact needs and will typically have lower idle usage. It's just slightly more involved due to extra wiring and fuses over an all-in-one.
I didn't realize that one could charge from shore and solar at the same time. Isn't that kind of dangerous for the lifepo batteries? Wouldn't the two chargers interfere with each other's charging profiles?
 
I didn't realize that one could charge from shore and solar at the same time. Isn't that kind of dangerous for the lifepo batteries? Wouldn't the two chargers interfere with each other's charging profiles?
Both charging profiles would be setup the same.

It's not uncommon for people to have multiple charge controllers all working at the same time.

The only potential issue is that you need to make sure the combined charge current isn't higher than what the batteries can take. Most decent charge controllers and chargers let you set the max charge current. So if you expect to use solar and shore power together regularly then you can set them as needed to avoid sending too much charge current to the batteries.

This would be one small advantage, I think, of an all-in-one. Since the charge controller and charger are in one unit it should be trivial to set a single max charge current and then the all-in-one will ensure it only sends that much current to the battery even when using both solar and shore power at the same time. At least that's what I would expect an all-in-one to be able to do.
 
Forgot to mention, The Digital Mermaid is documenting her journey making a 48V 280Ah system for a sailboat she purchased and is using Victron equipment.

That is one big heavy DIY battery bank (6 x 48 VDC x 280 Ah = 80.6 KWh).

I hope her boat still floats !!!

Digital Mermaid LIFEPO4 Battery.jpg


 
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Hi - I'm setting up a solar system on a boat with a 280ah 48v battery made up of eve cells. I'll have two 435w panels putting out about 80v each, running in parallel. I'm trying to decide if it would be better to run an all-in-one inverter charger, like the growatt or MPP, or if I'd be better off with individual charging and inverting components. One of the things that's pushing me away from the all-in-one is the heavy idle watt consumption on these boxes. What I'm wondering is if there is a good charger that can use both shore power or solar, and can automatically switch from one to the other. Any thoughts?

Thanks-
what do you think of Victron Energy BlueSolar MPPT 100V 20 amp 48-Volt Solar Charge Controller?


specification sheet says 1160W max solar with 48V battery

max 100V PV input, max 960W charging (48V*20A)

435W * 2 = 870W

in the victronconnect app, 59.56V is the max charge voltage it seems to support, which is plenty more than 3.65*16= 58.4V
 
the charger above is solar only, no AC

maybe the victron easysolar might be an option, that is all in one inverter ac charger and solar charger.

if you've already built, no problem ?
 
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