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TechDirect BYD BMS in pre-built units: Can anyone read this Chinese label?

GVSolar

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Can anyone read this Chinese label? This is on the installed BMS in the TechDirect BYD pre-built units. Thx.TechDirect BYD BMS.JPGTD:BMS CU.JPG
 
Clever human. Thank you Carly. Anyone know what all that means? Or how to/if you can interface with it?
 
I would like to know were to buy those. How do you configure the settings, etc. There is nothing on the google machine about the model number or company.
 
TechDirectClub.com sells them for $150 - spec at their website. They come installed in the pre-built units that are now sold at BigBattery.com. As far as I can tell, there is no way to interface, program or read information from the BMS - hence my question about the translation.
 
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TechDirectClub.com sells them for $150 - spec at their website. They come installed in the pre-built units that are now sold at BigBattery.com. As far as I can tell, there is no way to interface, program or read information from the BMS - hence my question about the translation.

I should clarify,

I would like to know where to buy them standalone. The ones that Techdirect sells are pre-wired and have a bunch of stuff I don't need and therefore are too expensive.

I inquired at Techdirect but they were not able to help.
 
Is there any reason you want this particular BMS?

otherwise, Daly BMS would fit as well
 
It came installed on my TechDirect pre-assembled units - otherwise I'd choose another. I'd have to tear the whole thing apart to replace - just wish I could find a way to interface with it for cell level monitoring.
 
Is there any reason you want this particular BMS?

otherwise, Daly BMS would fit as well

I just want to know if I can source that BMS from other than china. Having major problems getting anything shipped from china...

Still waiting on an ANT bms I purchased 2 months ago... need to get up and running.

Anything other than China source for 8s or 16s daly bms would be welcome too.

Thanks
 
It came installed on my TechDirect pre-assembled units - otherwise I'd choose another. I'd have to tear the whole thing apart to replace - just wish I could find a way to interface with it for cell level monitoring.

So there is no way to configure settings on the techdirect BMS? I wonder how Techdirect set it up originally? Or perhaps it is made specifically for the BYD packs?
 
I just want to know if I can source that BMS from other than china. Having major problems getting anything shipped from china...

Still waiting on an ANT bms I purchased 2 months ago... need to get up and running.

Anything other than China source for 8s or 16s daly bms would be welcome too.

Thanks

at least deligreen on aliexpress said they are beginning to ship stuff on beginning of March, so... I dont think I can get any of the component until the beginning of April (assume corova virus dying down at the time)
 
I'm seeing in other threads that some people are saying that the BMS provided by Tech Direct Club in these enclosures is not doing cell level monitoring. I can't imagine that is true. Can anyone confirm this? Is it doing balancing? Does it have to be over 3.75 in a cell to balance? I'd really rather not tear it apart to check the cells manually.

I have 2 of these units, and I've tried both of them with an MPP Solar LV2424 Hybrid. Both units start to beep at below 23 volts. I assume that this means one of the cells is low. Once charging begins the beeping stops in a few seconds.

Has anyone else had their BYD BMS start to beep?
 
Yes. I did - and I considered that to be the low battery cut-off - and shut down the discharge test on my three TechDirect units. From my point of view, actual usable capacity of these units is from right before the BMS high voltage disconnect (HVD) and right above the BMS low voltage warning (LVD). The lack of cell level monitoring is from the user's point of view (we have no way to access the BMS readings). The BMS settings published by TechDirect indicate that the BMS is monitoring the individual cells (see attached, Chinese version included) - user's simply can't access those readings. If any of the smarter folks on this forum can figure out a way to access those BMS readings I'd surely appreciate any advice...
 

Attachments

  • BYD BMS 8S Program Ch.jpg
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Wow

I saw low voltage cut off is 2.2V, high voltage cut off is 3.75V

balance starts 3.6V but only 40mA

and of course no low temp cut off
 
The low temp is less of a worry than the fact that the balancing starts so high - and that the high cutoff is so close to it - hard to imagine any multi-cell balance happening unless everything is perfectly in balance already. Tightrope city. Unless someone figures out a way to monitor the BMS so the actual cell voltage can be seen - I'll just have to go for conservative charging numbers and hope for the best where longevity/capacity is concerned.
 
...and my units cut-out altogether at 28v on the built in meter - which is below any balancing at all. Urk.
 
These are the pre-built units - no way to access the individual cells without tearing the whole unit apart - or finding a way to access BMS readings or use the built-in adapter connections. It's a quandary.
 
Yes. I did - and I considered that to be the low battery cut-off - and shut down the discharge test on my three TechDirect units. From my point of view, actual usable capacity of these units is from right before the BMS high voltage disconnect (HVD) and right above the BMS low voltage warning (LVD). The lack of cell level monitoring is from the user's point of view (we have no way to access the BMS readings). The BMS settings published by TechDirect indicate that the BMS is monitoring the individual cells (see attached, Chinese version included) - user's simply can't access those readings. If any of the smarter folks on this forum can figure out a way to access those BMS readings I'd surely appreciate any advice...

Why does the english version of that chart have columns "Min, Standard, MAX" if you can't change any of the settings?
 
Beats me... perhaps it is a tolerance issue - or there is some way to communicate with the BMS that I'm not aware of - hence the question/thread.
 
Jus
Wow

I saw low voltage cut off is 2.2V, high voltage cut off is 3.75V

balance starts 3.6V but only 40mA

and of course no low temp cut off

I emailed Techdirectclub this morning asking about cell balancing and recieved this as a reply:

"The do on charge 200 ma"

So it balances when charging at 200ma apparently???
 

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