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Tex

New member
Joined
Jun 5, 2022
Messages
14
Taken me 2 years to establish an account, but finally here I am, :rolleyes:
Ok, Like to dabble in 18650 batteries, making small packs for power tools etc., got an excellent spot welder and some other gear.
I have also built a cell prismatic 200 amp battery for our caravan, with mostly Victron control gear.
Always eager to learn.
Added a divider under bed where the inverter lives, and a hatch outside, think I might need an incoming vent to outside in the inverter side now?
Got em on the inside.
 

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Korishan

Moderator
Joined
Jan 7, 2017
Messages
6,886
Welcome to the club! 😎
 

OffGridInTheCity

Active member
Joined
Dec 15, 2018
Messages
2,079
Yes, it can take a while! but the systems you create have the potential to operating for long time - very satisfying for me. It's not like a model rocket that you spend weeks building and then destroys itself in one afternoon :)
Welcome to the forum!
 

floydR

Member
Joined
Aug 23, 2017
Messages
1,468
Perhaps Copy and paste request your guidance from Andy's "Off Grid Garage" channel forum?
Later floyd
 

Tex

New member
Joined
Jun 5, 2022
Messages
14
Ok, here's todays comments to Andys videos from me, (yes it's long). and I have attached the files here as well.

Greetings.
Firstly a word of warning to all.
As a result of watching this mornings video I decided to review my settings in my backed up Victron settings folder (did anybody realise you can save/backup your settings)? And guess what? good old Victron tells me I cannot open any of the backups (or restore them to the device) as "they were created in a previous version".
So, I suggest each time Victron enforce a firmware update (which seems to be often), back up your settings again and delete the old version.

BTW way there was no discussion about backing up the MPPT settings file in this mornings video.

Oh Andy! I was so excited about this mornings video, but I must admit a little disappointed at the end.
Firstly thank you for explaining several things that I have been unable to confirm from any Victron dealer, I love your application of good old German logic.
However, once again we are talking about stationery systems, in fact mostly DIY stationery systems.
The fact is the vast majority of solar battery systems in sunny hot Australia are MOBILE!
You could probably count the off grid DIY stationery battery systems in Oz in the thousands, you can multiply that by several hundred at least for mobile systems, mostly RV's of various kinds.

So all of us folks with mobile systems really do have different requirements. Yes we may actually run our battery down to 60% during the day, and yes we may need to start re bulk again.
And that may or may not involve tail current, who knows really?
I have two other issues I would like Andy to cover.
The first is Separate Port BMS's. In an RV you really want the BMS only to cut the charger and not the load when you are in the middle of making a coffee.
You can forget all the comments about separate port BMS having low amperage charging rates, firstly you can order them to spec, secondly considering the battery (weight) and solar (dimensions) limitations on an RV you are hardly likely to overload it.

Secondly is the Victron BMV-712. As anyone who has one (or an earlier version) they will be networked to (and overriding/controlling) the MPPT regulator.
In this situation all the important settings are set in the BMV-712 and there are HEAPS of them!
I found it useless to consult Victron regarding any clarifications on these settings as every dealer just refers you to their YouTube video on the device, which is generic at best.
So p[ease Andy lets give a leg up to the many thousands of guys building DIY RV LiFePO4 battery systems, especially the recommended BMV-712 settings (for mobile applications).

Hope you enjoy your $10 worth of SPATS, I have emailed you my currents settings and the network screen shot as I cannot upload them here.
Stay charged everyone.
 

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Dr. Dickie

Member
Joined
Sep 23, 2020
Messages
341
I think (and remember I am an idiot) Andy's point was. After achieving the bulk voltage 3.45 per cell and adsorption, the input should hold the cells at float voltage (3.35 V per cell) once you drop down to that level. As you drawing more, float should increase the current coming in to maintain 3.35 V per cell. IF you are drawing more than what is coming in, going to bulk again will not make any difference-as you have 100% coming in already to maintain float. There is just no reason to go back to 3.45V per cell once you hit it once that day (that should be high enough to top balance the cells--right at the cliff of the curve). At least that is my understanding, I could be wrong. Will be interested to see what Andy says.
 
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