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stevomyatt avatar image
stevomyatt asked

Lynx Smart BMS Force Absorption/Initiate New Charge Cycle

Hello,

I have a Lynx Smart BMS with 2x 25,6V Victron Smart Lithiums in series + Cerbo + Multi II & MPPT chargers.

Is it possible to manually initiate the (DVCC) absorption CVL aka New Charge Cycle (56.8v)?

I.e. in the situation that the CVL is float (54v) for some time less than the repeated absorption interval and greater than the SoC threshold.


From battery manual:

battery-manual.png

From Lynx BMS manual:

lynx-manual.png


BMSDVCC
battery-manual.png (65.0 KiB)
lynx-manual.png (63.7 KiB)
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2 Answers
Stefanie (Victron Energy Staff) avatar image
Stefanie (Victron Energy Staff) answered ·

Hi @stevomyatt,

for that to happen you need to alter/decrease the State of Charge threshold to a value below the actual SoC via VictronConnect app.

edit: or disconnect one of your DVCC managed MPPTs from the GX device. That will put the MPPT from External Control into normal mode and there MPPT should start charging your batteries just like normal.

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kevgermany avatar image
kevgermany answered ·

Why do you want to do this? Not needed for Lithium, self discharge is negligible.

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stevomyatt avatar image stevomyatt commented ·
Hi @Stefanie , thanks for the reply. I haven't changed the SoC threshold yet, I'll do some testing with that! It would be cool to have a selection on the GX controller under the Lynx BMS device to initiate a new charge cycle, somewhat similar to the Equalization function under the Multiplus Advance menu (not applicable for lithium obviously).

Hi @kevgermany , reason being because my system has been floating for a while, up and down by about 5% SoC every day/night on the solar, and I like the idea of being able to force an absorption when I'm plugged into mains. Essentially just a bit of manual control to keep on top of a well balanced battery rather than waiting for the repeated absorption time interval.

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kevgermany avatar image kevgermany ♦♦ stevomyatt commented ·
Maybe think about forgetting it. All you're doing as adding complications and potentially shortening the battery life. Not sure if you're aware, but ideal SOC for storage is 50%, by letting them drift down a touch you're doing no harm.
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