Pace BMS - reset to 100% SOC ?

Question

question

4711austria asked Jun 22, '24

Pace BMS - reset to 100% SOC ?

Hello,

how does it reset, if the CVL is not reached and the MP2 does not provide more Voltage?

This is the setting inside the Pace BMS (Gobel Battery SR1 PC200):

CVL 55,2V, under 1A it should reset the SOC to 100%

the MP does 55,2V and not more (DVCC is topped at 55,2V), through losses only 55,12V are measured on the BMS, current gets to zero.

It never reaches the 55,2V to reset, the SOC is completely off through a week and the SOC number is not worth looking at.

So how do I reset the SOC by not manipulating manually each week?

THX

cerbo gx BMS viktron mp2

bildschirmfoto-2024-06-18-um-175651.png (14.6 KiB)

2 |3000

Attachments: Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

pwfarnell answered · Jun 22 at 04:14 PM

Just to put the answer up again as I accidentally deleted it. Hace you tried setting SVS on in the DVCC menu so the MP uses the measured battery voltage to allow for voltage drop.

3

2 |3000

Attachments: Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

4711austria commented · Jun 22 at 02:39 PM

that's it, SVS on and it works (again), perfect, this I was looking for over a week and such a simple solution

perfect! thx.

1 ·

dutchsolarfreak commented · Jun 22 at 04:18 PM

I adjusted this DVCC parameter: Max charge voltage.

My Pace BMS setting are 55.2 1000mA. SOC is set to 100% when BMS reaches 55.2V and current drops below 1A

0 ·

1719072994261.png (57.5 KiB)

4711austria dutchsolarfreak commented · Jun 23 at 05:25 AM

the CVL from the BMS is higher rated as the DVCC Voltage, the MP will not go over the CVL.

0 ·

Modifications Space

Node Red Space

Answer 1 · 2024-06-22T04:53:28Z

Alexandra answered · Jun 22 at 04:53 AM

@4711Austria

Set your pack (trigger) charged voltage slightly lower. This is how it is done on a BMV.

Or adjust the MP2 in its internal settings a little higher to compensate for the V drop.

When you say you capped the voltage in dvcc you mean you capped it manually? Why?

How long is your absorption time set to on the system?

1

2 |3000

Attachments: Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

4711austria commented · Jun 23 at 05:26 AM

This is not possible, the CVL reduces the Voltage output on the MP.

0 ·

Answer 2 · 2024-06-22T05:20:27Z

4711austria answered · Jun 22 at 05:20 AM

If I set the BMS CVL lower, the MP corresponds to this setting on its maximum voltage.

The MP does not go higher then CVL, the DVCC is for a example 1V higher, it does not care the CVL is the limit.

So I cannot set the trigger to 100% SOC lower and I cannot set the MP2 higher.

What do I miss? (7h)

I also have a MPPT RS450/100, shouldn't it go 0,4V higher?

2 |3000

Attachments: Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Answer 3 · 2024-06-22T07:48:09Z

nickdb answered · Jun 22 at 07:48 AM

The system honours the lower of the BMS/DVCC limits so if it is exceeding CVL, either something is off in wiring/setup, or, using settings like keep batteries charged will inherently run a bit higher.

Ultimately the system will do what it is asked to do, the voltage increase is more likely a sign of the BMS not managing the battery charging properly - Pace BMS's are generally pretty poor and their SOC reporting is average at best.

This really seems like questions best suited for your battery supplier.

2

2 |3000

Attachments: Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

4711austria commented · Jun 23 at 05:29 AM

Pace is not the best for my Gobel SR1 PC200, I agree, but only on the SOC calculation as fare as I can see. The balancer ist an external Heltec with 4A active, so the pack does work fine, but the report of the SOC is not usable.

Looking for a better BMS, what is actually the best or is there a ranking out there?

0 ·

nickdb ♦♦ 4711austria commented · Jun 23 at 06:31 AM

I think the generic ones all have their quirks.

You obviously want one that is known to work well with Victron over CAN instead of relying on serial drivers etc.

The ones that get a mention (though still unsupported) are REC, 123/SMART, Boostech - though I cannot vouch for them myself.

You could also look at Orion.

Take your time to do some research.

1 ·

question