LIFEPO4 Battery discussion thread

[denmendez65]

and one of these:
View attachment 1909429View attachment 1909430View attachment 1909431

For what? He can already see that info. Only useful for LA batteries really

 

[denmendez65]

You need the main disconnector switch.

View attachment 1909436

part d is what DTBA was talking about from the other forum.

 

[wingnut771]

For what? He can already see that info. Only useful for LA batteries really

That info is lying though.

 

[denmendez65]

I am being dumb. Its a 2 pole already.

So just get 3 of these. Wire positive and negative through these to the busbars.

 

[DTBA]

I have a one from the busbar to the inverter as well. yes

 

[wingnut771]

I have a one from the busbar to the inverter as well. yes

Makes sense to protect the cable becoming its own hypothetical fuse.

 

[cavedog]

All positive and negative cables have equal length from the battery terminals to the busbars. Positive side cables of a similar length to the negative, including the fuse disconnect. If you want to be fancy, measure the ohms of the positive (including fuse holder) and cut it till you match the negative.

Equal length on the outgoing cable from the busbar to the inverter. Can throw in the main disconnector if you want, between the busbar and inverter (I have to check if it is a requirement for both positive and negative cables to be disconnected from the inverter in the event of isolation, I can't remember, mine is like that, it isolates both legs).

Thats how I would do it.


View attachment 1909424

I have a one from the busbar to the inverter as well. yes

So I modified @denmendez65 sketch just to include my fuse disconnect between the inverter and the busbars.

Do this sketch look corrtect?

 

[cavedog]

The only thing is cable length on the positive side will increase by 20cm for each battery because I need to add a link from the fuse holder to the busbar.

Cleversolarpower By Nick on YT suggest that won't have a big impact on current sharing between the banks so I think I will be good then I have 3 x batteries

Once that is done I want to get the Victron mppt installed and then someone must COC it for me again after the changes.

 

[wingnut771]

The only thing is cable length on the positive side will increase by 20cm for each battery because I need to add a link from the fuse holder to the busbar.

Cleversolarpower By Nick on YT suggest that won't have a big impact on current sharing between the banks so I think I will be good then I have 3 x batteries

Once that is done I want to get the Victron mppt installed and then someone must COC it for me again after the changes.

I dont think that matters.

Also, cant you just use your old CoC? What info does a CoC have?

 

[denmendez65]

So I modified @denmendez65 sketch just to include my fuse disconnect between the inverter and the busbars.

Do this sketch look corrtect?

View attachment 1909454

Just use 2 pole fuse holders. Thats the easiest.

Or as you drew it but it must be a 2 pole between battery and inverter that breaks positive and negative. The others can be single pole on the positive legs.

The choice is yours. Same same but different. But still same

 

[denmendez65]

I dont think that matters.

Also, cant you just use your old CoC? What info does a CoC have?

COC doesn’t care about equal length what what.

And it’s done on what you have. He didn’t have more than 1 battery

 

[wingnut771]

COC doesn’t care about equal length what what.

And it’s done on what you have. He didn’t have more than 1 battery

So it says 1 battery on CoC?

 

[cavedog]

So it says 1 battery on CoC?

Yes 1 battery and 1 inverter with the fuse sizes, inverter and battery serial numbers on it and with that he gave me a report of voltages at various points ground etc. Its a whole list. He signed it and its his department of labour paper not a generic thing and I signed. He keeps a copy and I keep a copy.

 

[denmendez65]

So it says 1 battery on CoC?

It will specify what you have

 

[DTBA]

Bought new batteries with zero series numbers on them.

Do they just make up numbers then?

 

[denmendez65]

Bought new batteries with zero series numbers on them.

Do they just make up numbers then?

How does factory know info about them? Nothing on the BMS?

 

[wingnut771]

Bought new batteries with zero series numbers on them.

Do they just make up numbers then?

Its Chyna. They dont follow any rules:

 

[wingnut771]

How does factory know info about them? Nothing on the BMS?

Why would they care? You have to pay shipping to China for warranty so people give up at that point.

 

[denmendez65]

Why would they care? You have to pay shipping to China for warranty so people give up at that point.

I guess so. I wonder what brand he has.

For stock keeping and tracking serial numbers are useful.

 

[DTBA]

I guess so. I wonder what brand he has.

For stock keeping and tracking serial numbers are useful.

yea the bms has one. how many people that gives COC login into the battery

Photon batteries