it charges and then goes into absorption mode, never goes to float. what setting do i have not set right?
tom
rec bms and victron multiplus 3000 12v and cerbo gx will not go into float mode
-
-
Rick OGM Support Staff
REC and victron have been working closely over this past year and updates are being released to take advantage of these emerging complementary technologies with more data being shared, more alarming integration and enhanced charging.
Updates released last fall started this and more are expected this year.
-
Thanks rick
Are you saying that it does not work with my 2.9.3 firmware bu t does with any newer firmware?
Tom
-
Rick OGM Support Staff
There have been quite a few advancements in LFP battery charging since firmware 2.9.3 but REC does not always share the details of the new features
-
i am still not able to get it into float mode. it stays in absorbsion can someone help me please figure out what setting to use? i have gotten some help from tine, but it didnt work.
tom
-
Rick OGM Support Staff
Are you using DVCC control so that it's rhe BMS that's controlling the charger?
-
yes
-
Rick OGM Support Staff
I will check to see with REC to see what the status on the latest release is.
-
tine sent me the latest firmware, but i am hesitant to use it after your comments the others experience.
tom
-
Rick OGM Support Staff
We now have 2.9.5 in house and will be doing some final testing and if all goes well we will release it in 1-2 weeks
-
can you tell me what the Charge Float Voltage Coefficient should be set at? it is a 0 to1 setting. i currently have it at .5, but i am still not going into float mode ever.
-
Rick OGM Support Staff
We just found a potential issue, so it could me a couple of weeks before we can release 2.9.5
-
Rick OGM Support Staff
@tom 0.5 is typical but you might want to experiment with setting it to zero. Here is the logic overview for 2.9.4. 2.9.5 may have a few tweaks.
Rick
Maximum Cell Float Voltage Coefficient (CFVC):
Maximum Cell Float Voltage Coefficient CFVC has been introduced into the charging algorithm to
enable cell float voltage change after the full charge. It may be set from 0.0 to 1.0 of the End of
Charging Hysteresis CHIS. When End of Charging Hysteresis CHIS and End of Charging SOC hysteresis
SOCH have been met, full charge is enabled again. 50 % of maximum charging current is allowed to
supply DC loads from MPPTs directly without discharging the battery pack below End of Charging
Hysteresis CHIS and End of Charging SOC hysteresis SOCH if CFVC is set > 0.0
-
BenPro user
@tom
Try these settings:
Settings:
Balancing end 3,55
Balancing start 3,45
max allow delta 0,25
end off charge 3,52
end off charge hysteresis 0,19
max allow voltage 3,65
max allow voltage hysteresis 0,1
min allowed Voltage 2,8
Min allow voltage hysteresis 0,1
min Vcel discharge 2,9
CFVC 0,9
SOCH 0,05
Which give:
Max charge 14,18V
float 13,4V
recharge if below 13,28 AND lower as 95%soc
Start with this, see how it works, and make changes to your personal wishes
-
BenPro user
@tom can you post your actual settings also.
This tell straight away or the suggested settings will help you.
-
@Ben
for some reason i cant cut and paste.
Balancing end 3.5
Balancing start 3.4
Max allowed delta .5
end of charge 3.55
end of charge hysteresis .25
max allowed voltage per cell 3.8
max allowed voltage hysteresis .25
min allowed voltage 2.8
min allowed voltage hystersis .1
min vcel discharge 2.95
cfvc .5
i do not see a place to read or set the soch (state of charge hystersis) so i do not know where to set this.
where do i set that?
my system is one i just built. 1100 amp hours of calb ca100 cells at 12v. everything else is working great. i have a vitron multiplus 3000 12v, 2 lynx distributors, rec abms, rec wifi, rec precharge. i also have cerbo gx with touch 70. wired in but not hooked up yet is two victron solar controllers and i also have the victron orion 50a dc to dc to charge my lithium off of of the freighliner cummins isx15 engine alternator. i just need to learn what i have not set up right yet. thanks
-
i see now where to check it. under firmware and the SOCH? it returns 5 e minus 2 which i think is .05 or 5 percent. is that right?
tom
-
BenPro user
@tom is correct.
It is factory setting, if you didn't change it before , it is set ok.
-
Any comments on my settings?
Tom
-
BenPro user
@tom one parameter is missing in suggestion
UBDI 0.025
UBDI, factory set at 0.008, accept a slightly bigger unbalance, which will result in a quicker switch to float.
Remember if cells are not in balance, system don't go in float.
Your setting gives a float from 13.7.
And restart to bulk if below, 13.16V AND below SOC 95%
-
i assume this is in balance enough. it is currently at 13.69v and still in absorbsion charge.
i am puzzled.
tom
cell 1 3.444v
cell 2 3.452
cell 3 3.450
cell 4 3.451
-
so a question. how do you determine my float should be at 3.7 from the settings i have? also, my victron multiplus has setting for absorbsion and float but i am assumming that the rec bms overrides that. is that correct? thanks tom
ben, i used to go to asia alot. china, malaysia, singapore, hong kong, korea, taiwan, japan and israel. since i retired i dont go anymore....thankfully.
-
BenPro user
@tom your system goes to float when battery reach the voltage 14 -14.2. If voltage dont go higher as 13.69, the system will not go to float.
You need to find out why voltage dont go higher, maybe batteries not full?
in VRM, you can select CVL?CCL, cell voltage / battery voltage/current. select last 2days in vrm. psot the 3 widgets here. this 3 widgets will show the information needed to trouble shoot
calculation float from settings, is a formula in the manual.
-
BenPro user
@tom did you make the new settings?
After that, switch BMS off and on, to start a new recharge cycle.
-
I will make the changes later today. It is 440am right now. Thank you
Soc shows 100 now before I make any changes. Thanks
Tom
-
BenPro user
@Ben I though you had the suggested settings already, seams not yet.
That explains you see 13.69, your system is in float, with a wrong , a bit high float programmed.
I have sent a pm also.
-
another question about float. is it even necessary to float lithium batteries? online it says it is not necessary. so staying in absorbtion is not an issue or not?
tom
Please login to reply this topic!
Search
Latest topics
Latest posts
Forum statistics
- Page views (24h):
- 200
- Page views (30d):
- 8,372
- Topics:
- 363
- Posts:
- 2,069
- Members:
- 1,053
