My research is failing me. I can’t seem to set my Bulk voltage on my 150/70 solar controller for my LifePo4 Battleborn batteries. Battleborn says Bulk voltage should equal Absorption of 14.4 volts. The controller charges Bulk at 13.6 volts no matter what I try. Any Ideas?

Bulk is just the charger trying to reach Absorption voltage using the maximum available power. If you’re seeing 13.6V in Bulk, it’s likely just because there’s not enough amperage available to reach the 14.4V set for Absorption (possibly because the sun isn’t high enough in the sky, or the batteries…

Hello Travis. Thank you for the reply. Yes, that’s exactly what happens. 13.6 until absorption then 14.4 as I set in the settings. However, I guess I’m old school in dealing with power supplies. I set the voltage as priority and it sends amps as set or up to its amp limit. Battleborn says char…

Ah, I see what you mean about Battleborn recommending a Bulk voltage of 14.4V. I don’t have a ton of experience with LiFePO4 battery banks, but I believe they’ll accept a lot of amperage before the voltage increases beyond that mid-13V figure, unless they’re very near 100%, so I think your scenario…

Battle Born batteries need to see 14.4v for their balancing board to kick in, so Bulk/Absorb should be set to 14.4v and Float around 13.6 to 13.8. Travis is correct - your charger will show less than 14.4v as it’s charging because its output voltage is being dragged down by the load of the battery.…

Thanks Justin I didn’t know about the 14.4V for .5hr for every 100Ahr. I have three 270 Ahr BB, 810Ahr total in my RV. Before leaving home I isolate them and charge one at a time. When they reach 14.4 (my absorption setting) they almost immediately go to the float voltage setting and I stop char…

That sounds like you have the GC3s? Have a look at their manual, they’re pretty explicit about how to charge the battery: https://battlebornbatteries.com/wp-content/uploads/2022/10/BBGC3-Manual-Edition.PIM_BBGC3Rev020_04242024.pdf?srsltid=AfmBOoqqBVNjWXpyut_vmffHkNnMa-TF1XX5D2lwaIvVFVaQ4wYqu1IC Don…

It’s not the GC. It’s the model that came out before. Thanks for all your reply’s BB wants the entire charge cycle at 14.4. Bulk=Absorption. There is no float for the BB. I’ve spent years trying to figure out how to do that.

[image] Dhshammer: BB wants the entire charge cycle at 14.4. Bulk=Absorption. There is no float for the BB. You can only achieve bulk at 14.4 if you have a huge charger. What I believe Battleborn are saying is if your charger has a setting called bulk then set it to 14.4, the same as absorpti…

I have exactly same problem but with a slightly different setup. LiTime 140Ah LiFePo charged thru a Orion XS connected to IN → 95Ah outboard cranking battery GND → 140Ah LiFePo House Battery OUT → 150Ah LiFePo House Battery LiTime states that charging voltage should be 14.4V +/- 0.2V and 28A I…

Bulk charging means constant-current, in ypur case 28A, the voltage lands wherever, mainly based on battery chemistry and SOC, so forget about it. Then as the battery gets full, its voltage will naturally rise, and once it gets to 14.4V the charger will change into absorbtion or constant-voltage mod…

Setting Bulk voltage to 14.4

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Setting Bulk voltage to 14.4

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