JBD/Overkill vs JK/Heltec BMS

[Sanwizard]

confuse manufacturers with resellers, the producers in this case are JBD and JK, the others rebrand and sell

Actually, in this case we may both be wrong. Looks like the guys who make the software (Enjpower.com) also did the R&D on the hardware for JK/Heltec.
This is from 2019:

E&J technology group developed and produced high quality bluetooth active balancer for lithium-ion batteries, lifepo4 batteries, lifeypo4 batteries, lithium titanate batteries, NMC batteries, 2V single cell lead acid/agm/vrla battery. http://www.ejbattery.com/productview_35.htm The balance current with 1A(JK-B1AS) and 2A(JK-B2AS) widely exported to all over the world and got good reputation,and 10A balancing current version(JK-B10AS) which is under testing and can be ready to sale soon in end of May. And our R&D team also designed the active balancer BMS which will be available soon.

 

[Globo]

Actually, in this case we may both be wrong. Looks like the guys who make the software (Enjpower.com) also did the R&D on the hardware for JK/Heltec.
This is from 2019:

E&J technology group developed and produced high quality bluetooth active balancer for lithium-ion batteries, lifepo4 batteries, lifeypo4 batteries, lithium titanate batteries, NMC batteries, 2V single cell lead acid/agm/vrla battery. http://www.ejbattery.com/productview_35.htm The balance current with 1A(JK-B1AS) and 2A(JK-B2AS) widely exported to all over the world and got good reputation,and 10A balancing current version(JK-B10AS) which is under testing and can be ready to sale soon in end of May. And our R&D team also designed the active balancer BMS which will be available soon.

I'm not mistaken at all Jk and JBD are producers, the others are not

 

[Sanwizard]

I'm not mistaken at all Jk and JBD are producers, the others are not

So E&J are lying?

 

[Globo]

So E&J are lying?

it is not a matter of lying, a development company may be external to the company that makes and sells the boards, a software collaboration is not the decisive thing. For example, many companies take finished products, vary the apps and resell them with their own brand, often you pay for the brand and not the product (this applies to almost all famous companies in the green energy field)

 

[Sanwizard]

I took a spare JK/Heltec apart today and took some pictures. Attached to this post. This is the 100A version (0.6A balancing current).
The MOSFETs are Chinese, a G035N10N from Huayi Microelectronics. Surprisingly, the datasheet is available in plain English:

http://www.szhxmos.com/uploads/soft/2101/HYG035N10NS2P.pdf

Continuous current of 180A at 25C and 127A at 100C. Seems they're not pushing this one.
The micro-controller is an STM, in particular the STM32F103C8T6. I somehow would have expected there to be a Chinese micro-controller on it since the other components are. The Bluetooth module is based on an RTL8762C.

There is one bodge on the board as far as I can see. Not a big deal. This is version 6.0 of the board though. Temperature sensor is well glued in place. Soldering job on the cabling is good.

Interesting that there are no manufacturers markings on the circuit board. I saw E&J saying (enjpower.com) saying on their site they developed the JK modules with their R&D. Wonder if thats true.

 

[Nepakima]

I bought all 4 of my JK's directly from Heltec. I have two unopened 200amp versions I most likely will not use, as I have 2 Seplos BMS's on the way.
I have two 13KW banks running, another being top balanced, and 4 more coming. The Seplos will be for two of the other banks, so I will no longer need the two I bought from Heltec. (The two running will stay in service).
I paid $195 each plus shipping, so $415 for both. They are in NY.
PM me if you need one or both.

Could you enlighten us why you're preferring the Seplos over the JK's, after all the Seplos don't have 2A balance current, nor BT (I presume)?

 

[Sanwizard]

Could you enlighten us why you're preferring the Seplos over the JK's, after all the Seplos don't have 2A balance current, nor BT (I presume)?

They work with the Pylontech protocol, as do my inverters. So my hope is to have them directly connected, so the inverters get direct and true state of charge for the batteries. Their BMS's also comminucate together when placed in parallel, so the soc of multiple battieries can be reported to the inverters, and they more intelligently share the load.
I love my Jk's though, and they have been perfect so far, but I bought 4 of the Seplos Mason kits, so having a common BMS across all banks was preferrable.

 

[Nepakima]

They work with the Pylontech protocol, as do my inverters. So my hope is to have them directly connected, so the inverters get direct and true state of charge for the batteries. Their BMS's also comminucate together when placed in parallel, so the soc of multiple battieries can be reported to the inverters, and they more intelligently share the load.
I love my Jk's though, and they have been perfect so far, but I bought 4 of the Seplos Mason kits, so having a common BMS across all banks was preferrable.

Great. Yes, I've actually been torn between Seplos and JK. My setup will be a simple one, so I seem to be leaning towards JK for the Bluetooth and 2A active balancer.

 

[Sanwizard]

Great. Yes, I've actually been torn between Seplos and JK. My setup will be a simple one, so I seem to be leaning towards JK for the Bluetooth and 2A active balancer.

You cannot go wrong with either in my opinion.

 

[gray webber]

I bought all 4 of my JK's directly from Heltec. I have two unopened 200amp versions I most likely will not use, as I have 2 Seplos BMS's on the way.
I have two 13KW banks running, another being top balanced, and 4 more coming. The Seplos will be for two of the other banks, so I will no longer need the two I bought from Heltec. (The two running will stay in service).
I paid $195 each plus shipping, so $415 for both. They are in NY.
PM me if you need one or both.

What is the reason for not using the JK? I just ordered one for my 24volt 280a pack. I’m nervous. You have two in service so you must know if they are working good for you?
Thanks!

 

[Sanwizard]

What is the reason for not using the JK? I just ordered one for my 24volt 280a pack. I’m nervous. You have two in service so you must know if they are working good for you?
Thanks!

Direct communication with my MPP LV6548's were not supported by JK, as they only had CANBUS communications. (I believe they now do have RS485 in their new versions.)
I also bought the 6.9KW Seplos Mason kits when they first came out for $1000 each, so I also purchased new Seplos BMS's for my existing DIY 280ah batteries, so all would have the same BMS. The Seplos BMS's also support communication between each other to assure load balancing, which I think is a nice feature.
I have nothing but good things to say about JK/Heltec though, as they have been flawless, and have served me well. Even without communication with the Inverters, the batteries have stayed within a few mV of each other, and the cells balance to about .008mV. (Grade B Lishen and CATL 280ah).

 

[gray webber]

Direct communication with my MPP LV6548's were not supported by JK, as they only had CANBUS communications. (I believe they now do have RS485 in their new versions.)
I also bought the 6.9KW Seplos Mason kits when they first came out for $1000 each, so I also purchased new Seplos BMS's for my existing DIY 280ah batteries, so all would have the same BMS. The Seplos BMS's also support communication between each other to assure load balancing, which I think is a nice feature.
I have nothing but good things to say about JK/Heltec though, as they have been flawless, and have served me well. Even without communication with the Inverters, the batteries have stayed within a few mV of each other, and the cells balance to about .008mV. (Grade B Lishen and CATL 280ah).

Super good to hear! I will not have any MPPT communication needs I hope. Simple set and forget level of system. I’m very happy to hear the JK has done well for you and feel much relieved for my needs. I just too balanced and strapped my 8s pack together.
Tomorrow I plan to finish the insulated and heated box build around it then install the BMS when it arrives. The low temperature charge shut off really makes me feel safe. I am in a very cold and snowy zone where one never knows if the battery heat system will hold up and then “poof”. Cells toasted.
All good! Thanks again! I will post pictures of the finished build when done.

 

[JaVid]

What is the reason for not using the JK? I just ordered one for my 24volt 280a pack. I’m nervous. You have two in service so you must know if they are working good for you?
Thanks!

Can you give me a link for the one you ordered please?

 

[gray webber]

I’ll try?

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Having trouble linking? No good at this stuff.
I got it from Banggood. Google it with hi BMS and they have choices.

 

[gray webber]

Can you give me a link for the one you ordered please?

I will attach screen shot?

 

[Bob B]

I’ll try?

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Having trouble linking? No good at this stuff.
I got it from Banggood. Google it with hi BMS and they have choices.

There is more than one way to insert a link into your post ... but here is how I do it most of the time.

At the top of your browser window is what is called the URL address ... starts with http
1. Move you cursor to anywhere on that line and click once ... this should highlight the address.
2. Now, hold down the CTRL key on the keyboard and press the C key once.
3. Then, put the cursor in you post where you want to insert the link ....
4. Hold down the CTRL key again and press the V key once .... The link is now inserted

Those are the "hot keys" for copy and paste.

This may be a little weird if you have never done it, but once you get used to it it will become 2nd nature.
If, for some reason, the URL address doesn't highlight when you click it .... move the cursor somewhere else and click ... then go back and click it again ... then on to step 2.

 

[gray webber]

I will attach screen shot?

The model number is JK-B2A8S20P
2amp balancing, 8 cell, 200amp discharge.

 

[gray webber]

I’m doing all this on my iPhone so the actions you detail are not possible. I’ll figure it out some day soon if I want to share as I do.
Thanks for you affords.

 

[gray webber]

Can you give me a link for the one you ordered please?

I took a screen shot of the actual model
It’s. JK. 2amp 8cell 200amp unit. They offer about 20 models on this sight. I think the first pic had a different model shown?

 

[gray webber]

Found the listing on eBay for Canadian Solar 390 watt bi-facial panels. Screen shot posted. I like they will ship 5+ units when most only ship 10+. Their shipping is about 30% less then others I have looked into.