Raj35

Hi All
Removed 
 
 

So this is my DIY box 32 EVE 280amp 20mm shutter ply

So this is my DIY box 32 EVE 280amp 20mm shutter ply

So this is my DIY box 32 EVE 280amp 20mm shutter ply

https://x.alibaba.com/Av9reZ

So this is my DIY box 32 EVE 280amp 20mm shutter ply

@DeonBez it's the JBD 20S 500amp. On the BMS 3.5 full cell voltage 56v pack voltage. 2.8V cut off voltage and 44.8 pack cut off. Inverter 54.5v on all but i think 54v is the sweet spot.

So this is my DIY box 32 EVE 280amp 20mm shutter ply

So this is my DIY box 32 EVE 280amp 20mm shutter ply

Just my 2c DIY is great and cheaper when I started of cells were alot cheaper but not readily available my first batch i almost lost my R16K on Alibaba. Them tried Shenzhen Basen with provided me with 48 x Leshen 272amp. Also have 32 EVE280 which is running quite well no active balancer and my latest experiment 16 x 184amp svolt blades which seem pretty good aswell. ALL cell using a JBD bms's coupled with a SunSynk 8kw.

So this is my DIY box 32 EVE 280amp 20mm shutter ply

"The BMS should really be able to take the punch & not allow higher than required voltage/ amps."
Yes , that's my point exactly.  My take on this is that the BMS is pre-configured in order to serve its mandate , that is to protect the battery chemistry from critical over charging and over voltage.  If you even have the intention to 'hammer' your battery , then the BMS must be able to protect the chemistry from the 'hammering' . If a number of protection states have been recorded in succession , the BMS should passify and allow no more until the user is made aware of it  . 
In the end , the only way a owner should be able to 'hammer' a lithium battery , is to use up cycles quickly , but that should be it ! If cells become swollen , the BMS has not done its work , thats it.

Item: Svolt 184Amps 
Age: New
Price: R26000 Each
Payment Method Accepted: EFT
Warranty: None
Packaging: Yes Original 
Condition: New
Location: Durban 
Reason: Not in use
Shipping: Yes at buyer cost 
Collection: Yes

I have had a number of request for a BMS tie-up between a JBD BMS and the SunSynk inverters after I have created one for @Steve87 a couple of months ago. Our friend there in Durban , @Raj35 , has subsequently built two units  with success , but only after I have resolved some issues I have created in order to support the module remotely.
The module allows to connect with the JBD BMS via standard RS485 communications and also to Sunsynk inverters via a can bus connection . The module reads important BMS metrics from the JBD and converts this to a PylonTech based can bus protocol . The metrics involved are , amongst others  :
(a) Battery Charge Voltage Limit 
(b) Battery Charge Current Limit
(c) Battery Discharge current Limit
(d) Battery Voltage Measurement
(e) Battery Current measurement 
(f) Battery SOC measurement
The module has an on-module led indicator which  flashes at various rates in order to declare the healthiness of RS485 and canbus comms , amongst other. It also facilitates a board connection to wire a remote led onto.
Currently I have not designed a PCB yet , as I would like to introduce additional RS485 and canbus drivers in order to entertain bms communications with Axperts as well via the LIB protocol.
The module is open source in terms of hardware and software .
Below is an image of a Vero board rendition of the module , and you can see it is very simple and as a result low cost:

The actual circuit diagram refers down below :

 
I will ask @Raj35 to help me to create a detailed bill of materials , including preffered sources , e.g. Mantech . Apart from the Mornsun DC-DC converter , the parts are reasonable easy to obtain. The DC-DC converter is available from Mantech.
The main reason for choosing the Raspberry Pico over the ESP32 , is mainly due to cost , ease of flashing firmware and ease of communicating with Laptop Serial Terminal without the need of addition RS232 dongle.
I am currently developing a C Shell Command Line interface for the gateway in order to debug the RS485 and canbus . It will also allow you to set parameters according to your own needs. But more about that on another day.
 
EDIT : Credit goes to @JustinSchoeman for inspiring me with both his suggestion to employ a software based canbus library  , as well as work he has performed already on his own BMS gateway , if memory serves , Arduino based.
EDIT2: Credit also to @Raj35 for being very patient with me while resolving some issues regarding both hardware and software. And in addition his valuable inputs.
 
 
 
 

@BritishRacingGreen @Steve87
Just and update we have successfully built the JBD gateway communication between JBD and Sunsynk 8Kw @BritishRacingGreen thanks for all your assistance and expertise on this build much appreciated.

@BritishRacingGreen @Steve87
Just and update we have successfully built the JBD gateway communication between JBD and Sunsynk 8Kw @BritishRacingGreen thanks for all your assistance and expertise on this build much appreciated.

@BritishRacingGreen @Steve87
Just and update we have successfully built the JBD gateway communication between JBD and Sunsynk 8Kw @BritishRacingGreen thanks for all your assistance and expertise on this build much appreciated.

@BritishRacingGreen @Steve87
Just and update we have successfully built the JBD gateway communication between JBD and Sunsynk 8Kw @BritishRacingGreen thanks for all your assistance and expertise on this build much appreciated.

Busbar drilled and tapped for bms positive. 3x20 copper bar.

@NoordSolar cupolar trading they sell copper products. They aslo cut aswell in Durban they have branches aswell.

Busbar drilled and tapped for bms positive. 3x20 copper bar.

I would get some copper flatbar. Cut to length and drill. Then have them nickel plated. 

Hi @Raj35
I have been working in the film and television industry for longer than I care to admit and I can tell you quality Lithium batteries are worth every penny. Right now I'm sitting with 7 camera batteries, 4 X genuine Sony batteries and 3 X generic. All 3 generic are swollen in just 3 years. 
Perhaps we as consumers need to take a much closer look at the quality of the lithium that goes into the battery as well as the ins and outs of the warranty provided.

After a disco show from those indicator lamps, the Vestwood bank is balancing nicely:

But I think I can conclusively say that the Heltec on my Daly bank is toast:

Hi All
Just a guide when sizing busbar and wire. 
Ī