If I don't want to fully charge (to 14.6 to extend battery life)

Terrapin

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What happens to excess power when a overkill BMS's max charge is set to 14.5v and the power supply is from these sources:
(For the sake of this question lets assume all the sources shut down at 14.6v)

1. A Progressive Dynamics 45a multi stage trailer converter set to the lithium with the included jumper ?
2. A desktop variable 30w 10a power supply set higher than the 14.5*
3. A 120w folding panel with the included cheapo PWM set for solar.

I am probably overthinking but will it harm any of the devises If their own shut off limits are not reached and they remain inline attempting to charge beyond the BMS limit?

4. * Can the desktop supply just be set to 14.5 and the BMS be left at the factory 14.6 setting to limit the top battery voltage for long term storage? Or will can the voltage in the battery ever exceed the voltage of a charging source?.
(If I do this for storage I can let the Trailer fully charge the battery to 14.6 when we are using it. That would actually be cool for max capacity when it's in use.)

I just don't understand how the interplay works.

I will ask how the chargers amperage plays into this as well later.....
 

snoobler

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1. once 14.5 is reached, BMS opens the circuit, and the charger stops sending current because it can't. It's like you disconnected one of the charger leads.
2. See #1
3. Assuming set to above 14.5, see #1
4. Once 14.5 is reached, the PS lowers the current to maintain 14.5 until current stops flowing and the voltage stays at 14.5.

Harm can occur depending on the device, but those you list shouldn't have an issue.
 

snoobler

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At least you're asking before doing. I've paid some stupid tax in my process... to the tune of over $1000 in incorrect or redundant equipment.

And I'm not counting the $2700 in SanTan panels I purchased thinking I could go grid-tie before doing my research. I will use those bastids though, so not wasted!
 

Terrapin

Solar Enthusiast
Joined
Jan 4, 2021
Messages
315
Location
New England, USA
At least you're asking before doing. I've paid some stupid tax in my process... to the tune of over $1000 in incorrect or redundant equipment.

And I'm not counting the $2700 in SanTan panels I purchased thinking I could go grid-tie before doing my research. I will use those bastids though, so not wasted!
Freakin' so cool to know it's not "just me". But yeah I did just cancel a alibaba order, so Maybe not so much.... But seriously though, you and certain unofficial librarians are the heartbeat here. It matters! TY!
 
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