Hi Just wondered what is best to leave as the charge of the battery so as not to cripple it. Its currently set to 4%; i think i'm just having flash back to bad days of leisure batteries getting too discharged but is that ok or should i increase it?
Matt
Hi Matt, I think the 0% and 100% limits are calibrated on first use and are the minimum and maximum safe levels for the battery type, so at 0% there is still some left for safety. I think there is something about this in the Knowledge Base, I'll see if I can find it.
Cliff
matt
what you see is not what the battery can do. It is topped and tailed a bit to protect the battery but you don't see that as the usable capacity should be whats ont label. So your fears are managed automatically and transparently for you.
It is fine to go all the way to 4%. The time you may wish not to is if you have EPS configured and fear there is a likelihood of a power cut. In that eventuality the battery discharges from the floor you set to 4%
So does that mean the battery is only 100% DOD if we have the EPS circuits connected? 96% for everyone else?
For information to anyone wondering if you had EON install your GivEnergy gear they do not connect the EPS and do not offer or mention it as part of the install.
no, 100% DOD means you should get the capacity you purchased
No batteries will go below 4% unless being recalibrated, but thats factored into the capacity provided
https://kb.givenergy.cloud/article.php?id=10 - does this need to be updated? The brochure says that the 8.2kWh battery has "100% depth of discharge ( Out Now )" but the kb article says it's only 6.56 useable.
So which is it - apologies if I am being thick!
new ones are actually bigger to provide the headroom and avoid the custoemr confusion.
I will request that be updated
MikeJ there are a few KB's that are out of date. My AC3 and battery firmware are not recorded on the firmware changes yet either.
Though I do find it confusing that my battery gets down to 8% then stops discharging. The monitor does not suggest 100% DOD. If the monitor was programmed to show 0% but really there was 4% left I would be non the wiser without looking into the discharge numbers. I expect it does discharge 8.2kw and if I remember I will check this weekend.
THALL Regarding the 8%, you might see if a timed discharge to a lower percentage improves that - my system was only discharging to 7% in mode 1 (and mode 3). I did a timed discharge to 4% - subsequently in mode 1 it's discharging to 5%
andrew_bond I will give that a go. I currently use ECO and timed charge for the 4 hours Go. But can try timed charge and timed discharge and see what happens. Actually I will set that now!
My installer said to me that my 8.2kwh battery is 8.2kwh useable but reading this article makes me feel unsure now . Installed in June 2021 - is there a way to check my firmware / serial numbers or admin check, to confirm my useable capacity? It is a big difference between 96% and potentially 80%. Thankyou.
Griff There might be a better way, but in the 'old' portal you can see the real capacity of the battery by going to System > Actions > View > BAT Cell, then look at the 'Full CAP' value.
In the beta portal you can see:
1) the inverter firmware
"inverter card"-"general tab"
"inverter card" -software tab"
2) the firmware of the battery
"inverter card"-"software tab"
3) design capacity of the storage
"inverter card"-"software tab"
We have not made the actual capacity visible in the beta portal yet ( so I will add that to the backlog ), so as much as it pains me to say
4) actual capacity (Full Cap)
legency portal - "bat Cell" page. You will see Full CAP is higher than Design Cap
simon_swinburne Thankyou - I am just playing catch up (as I have only just discovered the forum this morning!) - my 'General' tab on the beta website shows 320Ah / 16.38kwh (obs 2x8.2s).
Legacy portal - 160/160 design and 202 & 194Ah full CAP - which is around 20.5kwh - and this makes sense as 120% or the design spec of 16.4kwh. Thankyou.
Similar note - not sure if it is just me, but to see my battery go down to 4-5% and then draw from the grid, I think I would rather see it go down to a displayed 0% (but know there is 4-5% in reserve)? Horses for courses but is this something you are thinking of?
Griff I too would like the battery to show 0% rather than 4% (or in my case 8% minimum no matter what I change) seeing 4% gives the impression of not getting the full 8.2kwh discharge
THALL yes, it is just an OCD thing maybe but seems more straight forward and simple for most to prefer. Hopefully simon_swinburne agrees!!??
THALL
The reason its 4% is in case you are off grid for an extended period of time. Apparently that last bit is the 'keep alive' for the battery management system and some other technical reasons. It isn't user accessible.
This is not a reserve like a "storm alert" managed reserve. That is user acessible and managable now. This last bit isn't so you cant bank on using it in any circumstances.
The only time you will see it go lower is if you recalibrate the battery. At that time the system needs to hit the buffers at both ends, so not an everyday occuance
I will take this back to discuss internally as i see the confusion, but do wonder if we would get confusion the other way?
simon_swinburne understood, completely. I think with EVs becoming the norm, people will more understand they don't have access to top and bottom of the battery (home or car alike) and so what people want to see is 0%-100% is what they use (even if it is (which I know is)) just a software tweek to display 0-100%. This is my gut feeling.
Also sorry I have posted a few times this morning - they are topics I am interested in and hopefully aren't time wasting questions for you guys? Thanks again..again!!
simon_swinburne I dunno, as the 4% is technically a system minimum why would an end user need to see it? I would think the end user needs to see their usable capacity only. What they can manage. A lot of people buying these kind of systems will not be interested in the tinkering side of things and would like nice simple settings and visuals. For me that would be the energy flow card updating frequently showing my current battery state of charge (the bit usable to me). A card showing mode 1 to 4, a card for smart tariffs and turning on that mode, so choose Octopus Go automatically sets charge to blah blah dynamic the rest. Simple simple stuff. I am an IT engineer but at home I try not to tinker, I try really hard to set it up once then leave it. It helps reduce the number of funny looks I get from the family :-)
Can I add a vote for showing 0-100% of usable capacity regardless of buffers etc.