Victron 100-30 or 100-50?

[RMNummi]

I’ve got a 2020 GT 25 FBT. Mounting new Zamp Obsidians on the roof. What’s the difference between the 100/30 and 100/50? Planning on about 470 total watts. Have a single 300ah lifpo. Which MPPT?

[waninae39]

The 100/50 gives you additional capacity if you need to add more panels. If cost is not the issue,go with the larger model

[JeffKim]

The first number is the voltage, the second is the output current. With 420W the maximum output current is 35A, so I'd go with the 100|50 for the $60 difference (get the Smart, of course). There's a Victron calculator, which you get to pick panels or set custom parameters, but it mostly confuses me.

[RMNummi]

Gracias Amigo.

[Mollysdad]

My system looked to be about 30 amps. I went with the 100/50 just because.

[TrvlngTinTin]

Here’s a Helpful solar charge controller calculator

https://explorist.life/solar-charge-...er-calculator/

[switz]

Better to buy over sized once than have to upgrade to it later from an undersized unit.

[uncle_bob]

Hi

If you have a near dead battery at 11V

*and*

Have absolute max sun on your panels

*and*

Everything is 100% efficient

470W / 11V = 42A.

The 35A device isn't big enough.

The 100V vs something lower side depends on how you wire up your panels. With panels in parallel, you don't need 100V. If you decide to do some fun with series connections, it's a good idea to go that way.

The one thing that is for sure: It's way cheaper to buy the 50A device now than to buy the 35A and then replace it with the 50A later.

Bob

[RMNummi]

Yup, 100/50 bought and delivered.

[vanderwielen]

Originally Posted by uncle_bob

Hi

If you have a near dead battery at 11V

*and*

Have absolute max sun on your panels

*and*

Everything is 100% efficient

470W / 11V = 42A.

The 35A device isn't big enough.

The 100V vs something lower side depends on how you wire up your panels. With panels in parallel, you don't need 100V. If you decide to do some fun with series connections, it's a good idea to go that way.

The one thing that is for sure: It's way cheaper to buy the 50A device now than to buy the 35A and then replace it with the 50A later.

Bob

Victron MPPT controller inherently limit current per a setting in the victron connect app / battery / limit current setting. If your solar array's output exceeds the controller's capacity, the MPPT will limit the output to its rated maximum (30A), effectively "clipping" the excess power. This ensures safe operation and protects your system components

[uncle_bob]

Originally Posted by vanderwielen

Victron MPPT controller inherently limit current per a setting in the victron connect app / battery / limit current setting. If your solar array's output exceeds the controller's capacity, the MPPT will limit the output to its rated maximum (30A), effectively "clipping" the excess power. This ensures safe operation and protects your system components

Hi

Actually I believe they limit on power / temperature as well. They have a number of safety features built in.

The point in the post is: If you want the full output of your solar to go to the batteries you would need the bigger controller in the case shown.

Bob

[RMNummi]

Good info. Thanks all. Went with the 100/50. Now to go find the Sunexplorer and swap it out.