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jacques-2 asked

Batteries not charging from grid in ESS "Keep batteries charged"

Hi. I've just upgraded my gel batteries to 2 x Pylontech UP5000 and have had my local installer configure. With ESS set to "Optimized with battery life" and minimum SOC set to 100% the batteries only recharge when there is solar, which I am happy with. When we have cloudy days and sustained load shedding and the ESS is set to "Keep batteries charged" then they do not recharge even though there is grid power, in fact the batteries discharge even tough there is grid power and solar. I though it might be the BMV700 conflicting with the Pylontech BMS, but powering off the BMV yields the same results

victron.jpg

My system:

Multiplus 48/5000/70-100 with Firmware 497

Colour control GX with v2.87

MPPT 150/70 with v1.59

Pylontech UP5000 x 2

BMV700 with v3.11

Any ideas on how to resolve this would be greatly appreciated.

ESSPylontech
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Alexandra avatar image Alexandra ♦ commented ·

@jacques@demaplastech.co.za

Check what the gx is set to use as the SOC of the system.

Settings - system setup -battery monitor.

Are the Pylontecs actually setup to talk to the system?

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3 Answers
Rob Duthie avatar image
Rob Duthie answered ·

Turn this off (Optimized with battery life), not required. for Pylontechs. without battery life.


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jacques-2 avatar image jacques-2 commented ·
Hi Rob. No sure you fully understood my question. The only way to charge the batteries is with Solar no matter which ESS i choose, look at the right hand screen shot... with ESS set to "keep batteries charged" the grid input falls away and the loads are fed from the battery, even tough there is Grid and PV.
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nickdb avatar image
nickdb answered ·

And toss the BMV.

Edit: based on battery specs, that isn't enough battery for a 5kVA inverter, the discharge limits on the UP5000 isn't wonderful.

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jacques-2 avatar image jacques-2 commented ·

Hi Nick,

According to Victron as from the shot below, you need 4 x US2000 for the Multiplus 48/5000/70 which is the same or even less than 2 x US5000... so the batteries are not the issue. capture.jpg

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nickdb avatar image nickdb ♦♦ jacques-2 commented ·

It's not about capacity, the UP5000 has a low-ish discharge current, which is not far off the 3000.

So while you have more capacity, you actually have less current per kWh and are beneath that provided by 4 modules. The packs can't discharge sufficiently under load and may well have an issue sinking power from larger load disconnects with ESS.

All this causes BMS issues and unexpected behaviour.

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jacques-2 avatar image jacques-2 nickdb ♦♦ commented ·
Thanks Nick - I see what you mean. My issue is not on the load side though. When I have grid available and ESS is set to keep batteries charged, then I would expect the batteries to get recharged from the grid but they actually keep discharging themselves. The only way to recharge the batteries is with ESS on "Optimised with battery life" and then the solar recharges them no problem, my worry is that when its overcast and we have no PV but we have grid available, then they wont recharge.
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lifeingalicia answered ·
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