Ronski's Solar & battery DIY build with whole house backup

Soldato
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The first Victron parts have arrived.

MPPT-Shunt.jpg
 
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JA Solar JAM54S30-395/MR Black Frame Half Cell Solar Panels x 12
That will be a nice boost to your system.

Tried the cells and BMS yet? my last 8 cells I just bolted together and let the Sun and BMS balance them all out.
10 days of not very good weather and they are all good, 2A balance is a godsend
 
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No, not yet, was planning on testing them, top balancing etc but just not had the time, will end up doing what you have and let the BMS sort it out.

Have you compressed your cells? Would like to do mine with springs, but still need to get my head around that.
 
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No, not yet, was planning on testing them, top balancing etc but just not had the time, will end up doing what you have and let the BMS sort it out.

Have you compressed your cells? Would like to do mine with springs, but still need to get my head around that.

First set I built (8S/105A) I taped up the pack with Kapton tape.

Last two packs (8S/280A) I have not bothered, all I have done bolt the busbars down, and used card to separate the cells.
My packs have an easy life, think they tend to swell/expand if they are charged up too quickly.

I've not had any issues with them not compressed so far.
 
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There seems to be a lot of conflicting advice and opinions, so I'm not really sure. The most my inverter can constantly pull is 160A, which is 0.57C, once I have two packs it will be half that. Maximum charge current is 140A, so 0.5C with one pack, don't know if that would count as an easy life.
 
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Soldato
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Yes, I've sorted the breakers, pretty sure I originally bought the ones you linked to for the battery rack, I'd also bought some smaller ones for other duties, but it transpired that they are not by-directional, and therefore could catch fire in a fault condition with reverse current flow.

I've purchased a complete set from https://www.zjbenysolar.com/ via Alibaba, experience so far has been excellent. SolarEdge actually suggests using ZJ Benny in some of their literature, and their breakers are 'no polarity', so bidirectional which is what we need. They should all arrive next week.

I ended up going with a 160A breaker for each battery, and 250A for the whole rack. Victron states to use a 400A fuse, which I have, but a breaker doesn't trip instantly and will easily handle substantially more for short periods of time, you just need to understand the trip curves. I've also ordered two of their 32A 4 pole DC isolators for the PV strings, electrician said I had to have them, an MCB was not sufficient.
 
Soldato
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My Mega fuses arrived today (still waiting on the t-class fuses).

2 x 200A for the inverter cables
2 x 60A for the MPPT charge controllers

Also my bolts, nuts and washers arrived, still waiting on the copper lock washers, but my Lynx Power In now holds fuses.

Lynx-Power-In-with-fuses.jpg


This also arrived today, its a lot smaller than I thought it would be.

Cebro-GX.jpg


Inverter should be arriving Monday.
 
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Looking good Ron so far, I do love the colour of blue for the Rack.. perfect really.

The best bit is going to put all these parts together mate, please check your serial number of the Cerbo as their is a PSU issue with certain batch's and ONLY affects 48v systems...

Cerbo GX, part number BPP900450100
Serial numbers: HQ2201xxxxx up and including HQ2220xxxx

The fix is put a capacitor across the input power to the unit... I just received my Cerbo yesterday and looking to get it swapped out. Cannot figure out if or how to attach the notice.. I will email it to you mate.
 
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