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steve-french avatar image
steve-french asked

Victron EasySolar configuration with small battery bank

Hi Folks,

I'm looking for advice on the configuration of a Victron EasySolar 3KVA system configured as grid-connected, zero-feed in ESS. I have eight 12v 100AH Hankook DC31MF leisure batteries configured as 4P2S giving me a 48v 200AH bank. The battery SOC seems sit around 95%, occasionally hitting 100% in the summer.

This has been running for a couple of years but I'm finding that most of the time the system seems to be cycling between a few minutes of Inverter On (discharging) until I see a "Low Battery" warning, followed by a few minutes of charging. The other "issue" I have is that whenever the mains power fails there seems to be insufficient battery power available to power the system - this results in an outage.

So, I have a couple of questions:

1. Is the battery capacity "sufficient" to use in this configuration and should it be able to perform as a UPS (albeit in a limited capacity) when mains power fails?

2. Is the discharge/charge cycling to be expected - looking at the system now I have 120W AC load and its cycling every few minutes...?

3. In the absence of any specific data for these batteries, I have them configured as Gel/AGM as this seems to match the only data I manged to get from the manufacturer:

Manufacturers Recommended Battery Voltages
Daily Cycle: 14.4 (57.6)
Float: 13.2 (52.8)
EQ: 15.5 (62)

My Configuration (Note: Float is a little higher than manufacturer recommended):

1610632271926.png


Dynamic Cutoff is also at the default for Gel/AGM - is this ok?

1610632460248.png

Restart Offset:again default for Gel/AGM is this ok?

1610632609865.png

Any help/advice gratefully accepted!!


EasySolar All-in-One
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1610632271926.png (26.4 KiB)
1610632460248.png (3.1 KiB)
1610632609865.png (1.7 KiB)
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3 Answers
dazey77 avatar image
dazey77 answered ·

I think you mean your bank is 4S2P (two parallel circuits of 4x12v in series, so effectivly 2 x 48v in parallel and the 200AH you say)

I would suggest you check each battery and see if one has failed.

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steve-french avatar image steve-french commented ·

Yes, you are correct they are configured as 4S2P (I thought that but typed the opposite - doh!)

Does the behavior indicate a failed battery - ie: should it be able to work with a relatively small (and leisure type) battery bank?

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dazey77 avatar image
dazey77 answered ·

It depends a little on the loads. If its only lasting a few mins and the system is actually pulling 3kw, then its probably performing correctly. If your only pulling a few watts and its lasting a few mins, then its probably got an issue!

if I understand right and your only pulling 120w for a few mins then something is not right. The batterys should be able to support that level of load for a long time.

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marekp avatar image
marekp answered · 
2. Is the discharge/charge cycling to be expected - looking at the 
system now I have 120W AC load and its cycling every few minutes...?

This info suggests that your battery is toasted.

Check voltage of each battery individually during charging and discharging.

Do you have battery balansers?

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