New off grid 48v build

Bigfillly

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Aug 20, 2017
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112
Hello everyone,
Im new to all this but I like a challenge,
Ive been watching hbpowerwall on YouTube for the past 3-4months and thought Id go the way he has,
Im getting through the testing of 18650s but its a very long process, Ive built 12 pack up to now,Here what else Ive gathered together so far:-

3x285w solar panels
PIP-5048HS mpp solar
2000+ 18650s

I should be able to make over x24 80 battery packs (like hbpowerwalls ?) do I need 12 pack for 48v as Ive seen people use 14 packs?

My plan was to buildx12 80 battery packsto start with (for the 48v)thats why I only got the x3 solar panels, Im now building 24 packs so will get another 11 solar panels in a few months,
still got a lot of batteries to test,

image_rbhcfa.jpg

Any advice would be great,
Thanks,
Phil.
 

DarkRaven

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To fit the 48V system you need 14 packs in series. 12s would be ~36.0V to 50.4V, that's too low for 48V.
 

Bigfillly

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Aug 20, 2017
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Thanks for that, I did wonder, I should have enough batteries for 28 packs or very close anyway,
Ill keep everyone posted,
Thanks,
Phil.
 

daromer

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Yeah going that PIP you should go 14s as said.

You can always do the 2nd string smaller in terms of cells per packs or you just wait :)
Thought about BMS?
 

Bigfillly

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Hmm not sure about a bms, Ive not thought that far ahead yet, what do you suggest?
 

daromer

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You ask the Batrium guy now :) So I would say Batrium and if you search the forum my name + Batrium will show up everywhere hehe
 

Bigfillly

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ha ha, I should have known really, Ive watched enough of yours and hbpowerwalls videos to know you would say the batrium system, What other cheaper ones is there available?
 

daromer

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No cheaper one that do the same things no. So what function do you want/need? How reliable do you want it to be? I did take a look at a cheap Chinese version for around 50-60 USD piece. Only 50mA balancing and buggy and you need 1 per string but it works.

I dont get anything for promoting that product though since I cant affiliate link it :p
 

Bigfillly

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:D :D :D
Ill have a look as Ill be needing it soon enough, in the mean time Ill be testing, testing, testing them batteries :dodgy:
 

Bigfillly

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Hi,
As I only have the 3 solar panels at the minute, I may as well mount them, will it be ok to use them in series,
Like this but with 3 panels

image_tpseyy.jpg


This is the spec of the panels

image_pckihq.jpg


and also with the PIP-5048HS inverter be ok with them in series?
Thanks
Phil.
 

DarkRaven

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Take the specs of the panels, voltage times three and compare with the specs of the inverter. If it matches then it won't be a problem.
 

Bigfillly

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Thanks very much DarkRaven ;)


image_skiqyo.jpg


All look so good to me but can someone explaine what appliance mode and ups mode is please,
Thanks,
Phil.
 

DarkRaven

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That is the AC input from the grid, you have to look at the bottom where it says "Solar Charger" since the solar panels are your solar input, obviously :)
 

Bigfillly

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Aug 20, 2017
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Ha ha, what a novice I am :D
I see from the panels they are 38.78 voc and 31.15 vmp so either way the VP input will be greater that the 90v the inverter allows, so I cant do them in series,
Ill use the 3 into 1 plugs to bring all 3 panels into 2 leads for the inverter,
Thanks very much again for your help DarkRaven ;)
 

Bigfillly

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Aug 20, 2017
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Quick update:-
Ive found a place to put it all, its going in the conservatory, I know its cold here in the U.K. at the moment and I realise in the summer it will be hotter in there but I will tackle that when Summer gets here,

Ive been doing a little work over a few days and it looks like this at the moment:-


image_czfhni.jpg


As you can see there is enough room on the left for the inverter, fuses, trip switches and Isolators,
I plan on having doors covering everything apart from the batteries which I will make a feature with LEDs,
on the top right (where the window is behind the blind) Ill put a screen on that door for monitoring the batrium system,
Ill use the windo for venting the heat, maybe with fans,
Please let me know what you think,

Oh and please be kind :D
 

daromer

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UPS mode switches in 10ms meanwhile appliance mode switches takes up to 20ms. The difference is if the inverter is up and running all the time or it starts up when switching. Can be compared to online-ups vs cold (Dont remember the name)

The Appliance mode tend to work fine for most users.
 

Bigfillly

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Aug 20, 2017
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A little over my head without having the inverter here (not delivered yet) but I think I get the idea, Ill be leaving it in appliance mode,
Thanks very much once again DAROMER (the master) for straightening things out :D
 

wim

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Apr 6, 2017
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Bigfillly said:
...
on the top right (where the window is behind the blind) Ill put a screen on that door for monitoring the batrium system,
Ill use the windo for venting the heat, maybe with fans,
Please let me know what you think,

Oh and please be kind :D

Onlykind people here... ;)

Nice setup and it is smart to go for a decent bmslike Batrium...

Only concern i have is on the fire-proofing of things... the 18650 are pretty stable and will not burstinto flames without a reason.
Mostly the reasonis human error, and since this is a diy build... andwe all make a stupid mistake soon or later.
So if you have no way of putting the cells outdoors away of livingspace, then you have to think of making the inclosure fire resistant... use metal instead of wood, with a decent door to close the compartment.
If wood is the only option, atleast apply a coating of some fire retarding stuff (forget the name, but it turns ino a glass-like finish).
There are alot of things you can do to make it safer..
A fire detector and a extinguisher at handywould be nice. :idea:

Just some things to think about.
 

Bigfillly

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Aug 20, 2017
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Hi wim,
Thanks for the kind reply :D
I did think about If a cell caught fire and it all being wood, they dont really mix do they,
Its a long way off finished, so Ill look into the paint and give it a coating, thanks for that,
The conservatory has patio doors separating it from the house, so if it did go up, it would hopefully be contained,
oh and I always have an extinguisher very close to hand ;)
 
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Bigfillly

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Aug 20, 2017
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I have a few quick questions about the isolator switches needed,

1, what amp isolator switch would I need for 14 x 285w solar panels, each are just over 31v and just over 9 amps?

2, do I need 32amp isolator switches for the 240v in and outlets on the inverter/charger?

Thanks very much,
Phil.
 
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