diy solar

diy solar

BYD BMS

jasonhc73

Cat herder, and dog toy tosser.
Joined
Oct 1, 2019
Messages
1,921
Location
Wichita, Kansas
A no cut, no splice, plug-n-play.
It has a screen, Bluetooth, and more settings in the app than we know what to do with.

IMG_20200104_195834705.jpg

Will already reviewed this BMS.

The Inside wires:
IMG_20200125_211048192.jpg IMG_20200125_211058490.jpg
IMG_20200125_211110994.jpgIMG_20200125_211116809.jpg
IMG_20200125_211123362.jpgIMG_20200125_211137568.jpg

The Outside Wires:
IMG_20200112_100127974.jpg IMG_20200112_100451606.jpg IMG_20200112_100345578.jpg

Conclusion:

Molex Micro-Fit 3.0
430251000 10POS 3mm Molex Micro-Fit 3.0
or
1729521001 Micro-Fit TPA Receptacle Housing WITH Micro-Fit Terminal Position Assurance (TPA) Retainer

Molex
4303000001 12" PRE-CRIMPED Molex Jumper Wires
or Crimp your own wires
Micro-Fit 3.0 Crimp Terminal, Female


TE Connectivity AMP Connectors
1318772-2 12POS 2.2MM Tyco Electronics Header
1318745-2 32POS 2.2MM Tyco Electronics Header

Dupont Wires
Female to Female Jumper Cables

Green Mountain DIY Guy revealed a little secret about getting to the BMS on the BYD. (Sorry, no you can't use the BYD BMS, just have another way to get the connects to the cells)
 
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This is the BMS I chose for my system as well...

I got two without screens, and one with the screen.

I am WAITING PATIENTLY ... still not arrived yet...

tracking says it is here in Charlotte as of the 3rd... but nothing as for delivery.
 
  1. Open the cover and disconnect the 12 pin connector from the OEM BMS, set the cover aside.
    IMG_20200105_200800586.jpg
  2. Disconnect the 32 pin BMS and remove the BMS, stack it up with the rest, maybe one of your cats can figure out how to code it! (none of mine could)
    IMG_20200105_200803434.jpg
  3. Connect the 32pin adapter
    IMG_20200105_200817949.jpg
  4. Connect the 12pin adapter
    IMG_20200105_200917321.jpg IMG_20200105_200929491.jpg
  5. Close the back cover
    IMG_20200105_200948690.jpg
  6. Connect the 10pin connect.
    IMG_20200105_201047722.jpg
  7. Look at all the pretty numbers
    IMG_20200105_201429934.jpg
    Even through BlueTooth.
    Screenshot_20200105-210651.png
 
That will save a ton of time!

Do you use the 8S version of the bms from Ebay?

Can we purchase the 8 pin to 32 pin adapter cable someplace? If so please post a link.

Thanks
 
That will save a ton of time!

Do you use the 8S version of the bms from Ebay?

Can we purchase the 8 pin to 32 pin adapter cable someplace? If so please post a link.

Thanks

I dig your user name!
download.jpg
 
Give a few days for the parts list. I do not recommend doing it with this set that I used. I spent more than I should have and realized there is a much much simpler way to get the same result.

V1.0 parts list
  • 0430251000 10POS 3mm Molex Micro-Fit 3.0
    • I do not recommend this fully, it's for a machine to insert the wires and is difficult to do by hand, possible but an easier option is available.
    • I have the 1729521001 housing with the 1729531001 on order and should be here today or tomorrow. These have the same end that connects to the BYD battery the Molex Micro-Fit 3.0 10 POS, but the wire side is designed for human hands to insert and has two plastic locks to hold the wires in. I have a complete set of pre-crimped leads to make the process much easier, especially if you don't have the proper crimper to work on such small wires.
  • 0430300001 20-24AWG Sockets crimp tin
    • WM1837CT-ND at Digi-Key
    • This is what you have to use to insert into the Molex connector. It requires a special crimper (Like a Hozan P-706)
      • I think I can do the same thing in the V2.0 parts list without this, using pre-crimped leads.
      • 04303000001 12" PRE-CRIMPED Molex Jumper Wires.
        • 0430300001-12-R0-ND at Digi-Key
  • 1318772-2 12POS 2.2MM Tyco Electronics Header
    • This is the OEM connector on the BYD BMS
      • I think I can do the same thing in the V2.0 parts list without this, using breadboard jumper wires.
  • 1318745-2 32POS 2.2MM Tyco Electronics Header
    • This is the OEM connector on the BYD BMS
      • I think I can do the same thing in the V2.0 parts list without this, using breadboard jumper wires.
  • USB 1.1 9pin header connecting the 12POS to the 32POS
    • If breadboard jumper wires work, this won't be necessary either. (I'll know as soon as the jumper wires get here)
Everything is availabe for 2 or 3 day delivery from Dig-Key. If you can wait a long while for a slow shipment from China, you will save by buying on Alibaba/Aliexpress.
 
Yes - inside each BYD pack is 8 cells. Which makes 16 cells, in series. (and it's you are! (y):ROFLMAO:)
Hi Jason,
Watching your progress with great interest. I am considering purchasing several BYD 24v pack pre-configured enclosures from TechDirect for use in my off-grid system.
Would your BMS setup work as a "plug and play" replacement for their system - as an 8S? If not can you suggest another unit with the same features?
There is no cell monitoring or connectivity on the TechDirect BMS - but it does connect directly to the original wiring.
Also - are you charging using the original BYD trace wiring connections to the cells?
Thanks so much.
 
Hi Jason,
Watching your progress with great interest. I am considering purchasing several BYD 24v pack pre-configured enclosures from TechDirect for use in my off-grid system.
Would your BMS setup work as a "plug and play" replacement for their system - as an 8S? If not can you suggest another unit with the same features?
There is no cell monitoring or connectivity on the TechDirect BMS - but it does connect directly to the original wiring.
Also - are you charging using the original BYD trace wiring connections to the cells?
Thanks so much.

The trace wiring is plenty for cell balancing. A 24 awg wire is capable of 3.4 ish amps dc. The 16S BMS does cell balancing at only 200 milliamps.

The BMS that I bought will work on ANY configuration of 2 to 16 cells. It is pretty complicated in it's configuration though, but I am no expert and fumble farted around through it to make it work.

(Ebay link)
Techdirect made a very nice setup, and it is a true plug and play setup for the end-user. But they get to standby their work.
Don't forget where we are "here", DIY. :)

As it turns out the parts list to my DIY harness is not very expensive at all. I didn't do the math yet, but here are the preliminaries. The BMS that I bought is the 320amp version with the display. (Yea, sure 320amps, whatever) but that's what the nice China man said it is. (LOL) I am very impressed with its build quality, and it is extremely easy to install. They did a very good job at designing it making the connectors idiot-proof. (Poka Yoke design)

I spent a few more $ than I probably should have with the parts list I sourced, and will post the parts lists on this Plug-N-Play thread later this week, and basically have 3 options. I am hoping the least expensive option actually works! Because it's also the fastest way to make it work.

PS - When I saw that video from Techdirect with their connector It put me on the hunt to find that connector. If they can source it, so can I! But what they charge $195, I did for basically $110. $94 is BMS. For example, the 12POS header is $4.7 for the TE (Tyco) OEM connector here or 40 cents from Alibaba for a Chinese copy!
 
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hey gvsolar-do you have those 24V 5 kwh 200 Ah battery pack?
if so,where did you purchase the cables for that?from techdirect?

Thank you.
 
Still analyzing the units, on this and about a half dozen other threads. Right now my biggest concerns are:
a. no comms from the BMS - individual cell voltage are an ongoing mystery. And why I inquired about a replacement...
b. the website BMS lists 90C as the high temperature cutoff - everything I've read says 60C is already too hot.
c. vertical mounting of the battery - with the fan removed. See b. above. I'd probably add it back.
So far, TechDirect has been forthcoming with feedback - so the beat goes on.
 
Give a few days for the parts list. I do not recommend doing it with this set that I used. I spent more than I should have and realized there is a much much simpler way to get the same result.

V1.0 parts list
  • 0430251000 10POS 3mm Molex Micro-Fit 3.0
    • I do not recommend this fully, it's for a machine to insert the wires and is difficult to do by hand, possible but an easier option is available.
    • I have the 1729521001 housing with the 1729531001 on order and should be here today or tomorrow. These have the same end that connects to the BYD battery the Molex Micro-Fit 3.0 10 POS, but the wire side is designed for human hands to insert and has two plastic locks to hold the wires in. I have a complete set of pre-crimped leads to make the process much easier, especially if you don't have the proper crimper to work on such small wires.
  • 0430300001 20-24AWG Sockets crimp tin
    • WM1837CT-ND at Digi-Key
    • This is what you have to use to insert into the Molex connector. It requires a special crimper (Like a Hozan P-706)
      • I think I can do the same thing in the V2.0 parts list without this, using pre-crimped leads.
      • 04303000001 12" PRE-CRIMPED Molex Jumper Wires.
        • 0430300001-12-R0-ND at Digi-Key
  • 1318772-2 12POS 2.2MM Tyco Electronics Header
    • This is the OEM connector on the BYD BMS
      • I think I can do the same thing in the V2.0 parts list without this, using breadboard jumper wires.
  • 1318745-2 32POS 2.2MM Tyco Electronics Header
    • This is the OEM connector on the BYD BMS
      • I think I can do the same thing in the V2.0 parts list without this, using breadboard jumper wires.
  • USB 1.1 9pin header connecting the 12POS to the 32POS
    • If breadboard jumper wires work, this won't be necessary either. (I'll know as soon as the jumper wires get here)
Everything is availabe for 2 or 3 day delivery from Dig-Key. If you can wait a long while for a slow shipment from China, you will save by buying on Alibaba/Aliexpress.

i am trying to understand this process. i think when you say no cut means you are just diverting the connection via a different connector to the factory connector on the front plate?
i ordered
43025-1000 (https://www.molex.com/molex/products/datasheet.jsp?part=active/0430251000_CRIMP_HOUSINGS.xml)
43030-0001 (https://www.molex.com/molex/products/datasheet.jsp?part=active/0430300001_CRIMP_TERMINALS.xml)
43020-1001 (https://www.molex.com/molex/products/datasheet.jsp?part=active/0430201001_CRIMP_HOUSINGS.xml) thinking i will solder the battery terminal output and get it outside and use the other connector end to mate with 16S active balancer. obviously this seems to be the wrong connector or i missed ordering the terminal for this.
 
Still analyzing the units, on this and about a half dozen other threads. Right now my biggest concerns are:
a. no comms from the BMS - individual cell voltage are an ongoing mystery. And why I inquired about a replacement...
b. the website BMS lists 90C as the high temperature cutoff - everything I've read says 60C is already too hot.
c. vertical mounting of the battery - with the fan removed. See b. above. I'd probably add it back.
So far, TechDirect has been forthcoming with feedback - so the beat goes on.
have you used those batteries yet?
and if so-are they what they claim to be?
 
i just talked to a tech at techdirect,battery adapters come with it-you make your own cable length for it.
shipping takes 7-10 days,shipping company will call 2 days ahead for delivery.
 
have you used those batteries yet?
and if so-are they what they claim to be?
i have not but working on wiring up the setup soon maybe in a week or two. i was trying to get pointers from @jasonhc73 to see if i need to keep anything in mind as my setup will be similar but with 2 batteries to start with and 2 more coming in a few weeks.
 
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