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diy solar

diy solar

NW OH DIY Roof Mount Solar

I couldn't help myself...

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32 more EVE 304 cells. Two cases coming. The batteries showed up in 2 days, I was blown away! The cases are on the slow boat, it'll be 3-4 weeks before they're here. That'll give me around 1800 AH.
 
I both pity and envy you..

Good deal. Did you get them from the 18650 store? What did you pay for them?

Yep, they were $90 ea. When I first budgeted for them they were $105, the price difference basically covered shipping.
 
Yep, they were $90 ea. When I first budgeted for them they were $105, the price difference basically covered shipping.
Wow that's a steal. It's amazing how cheap cells have gotten in just a year, even. What's the advertised cycle life on these cells? Will you be compressing them, and have you compressed your other banks?
 
The 304 cells are rated at 4000 cycles but my 280's were 6000. All the 280's tested over 300AH. I haven't tested any of the 304's yet.

My first 4 packs are not compressed. I had 2 built before I really started researching it. The next 2 packs will in pre-fab cases from Shenzhen Yixiang New Energy Co. (https://www.alibaba.com/product-det...j8oj9l&bm=cps&src=saf&productId=1601123768920) The cases have compression built in.

I built my battery based off what a friend of mine did and he didn't use compression. His design was based off Andy from Offgrid Graage's build.
 
Woot! SolarAssistant did an update and now I can see all 4 of my batteries off one cable!!
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Been reading this thread. Very nice setup!! Excellent work!!
You’re using JK inverter BMS and have multiple JK’s in parallel with direct RS485/CAN communication with Sol-Ark.
My question:
1) How difficult to get JK and Sol-Ark to communicate in closed loop?
2) How many JK’s can be paralleled and when paralleled, where do the paralleled JK’s connect to? I know slave #1 RS485 back to master, but what if there 2 or more slaves?
Does pack #2 etc RS485 directly back to the master BMS, or does each JK in parallel daisy chain to each other and only slave #1 connects to master?

I have Sol-Ark with four LiFePo4 DIY 16s packs and about to add two more packs. Interested in the new Jk inverter BMS, thinking to add these if the communication works good between all these and I’m sure how to hook up that many BMS’s. So I’d be paralleling six total JK BMS’s.
My current setup works great, but really like the balance feature of JK.
Any help or advice/experiences are appreciated.
 
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Thank you! It's been a lot of fun doing all this.

1. Extremely easy - configured the JK and got it communicating with the others, connected it to the Sol-Ark, enabled sol-ark battery coms.
2. From what I've seen you can have a max of 16. Each JK connects to the next in a daisy chain fashion on the right hand side ports. The master JK (Set to ID 0 - this is important otherwise parallel doesn't work.) connects CAN to the Sol-Ark.

On the sol-ark side, there is a single port for CAN / RS485. I wanted to buy a nice breakout cable from the solar assistant folks but they were out of stock and I'm impatient so I built my own. Other than that, you just make sure the CAN pins match up.

Here's more detail for what I did.
1. Configured my JK BMS settings the way I wanted with ID 1 and did a firmware update. Made sure the CAN protocol was set to 002 - PYLON
2. Set the ID on the master to 0.
3. Configured the slave JK's with the same settings and updated the firmware, each time setting the ID to 1 to do it then changing to their position.
4. After each one was done, I connected a single RS485 on the farthest grouped RS485 ports.
5. Connected the CAN port on the Master JK to the CAN port on the sol-ark with the proper pin,
6. Turned on Activate Battery

Once that was done, the Sol-Ark just saw it and has worked ever since. I made sure I had all the settings in place as if I was doing open loop as a precaution.

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I thought I posted a pic with my splice box and didn't see one. Here's what I have for the RS485/CAN. It's just a surface mount CAT5e with 2 keystones, each wired with the proper pins so I could use the cables that were included.

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Thank you! It's been a lot of fun doing all this.

1. Extremely easy - configured the JK and got it communicating with the others, connected it to the Sol-Ark, enabled sol-ark battery coms.
2. From what I've seen you can have a max of 16. Each JK connects to the next in a daisy chain fashion on the right hand side ports. The master JK (Set to ID 0 - this is important otherwise parallel doesn't work.) connects CAN to the Sol-Ark.

On the sol-ark side, there is a single port for CAN / RS485. I wanted to buy a nice breakout cable from the solar assistant folks but they were out of stock and I'm impatient so I built my own. Other than that, you just make sure the CAN pins match up.

Here's more detail for what I did.
1. Configured my JK BMS settings the way I wanted with ID 1 and did a firmware update. Made sure the CAN protocol was set to 002 - PYLON
2. Set the ID on the master to 0.
3. Configured the slave JK's with the same settings and updated the firmware, each time setting the ID to 1 to do it then changing to their position.
4. After each one was done, I connected a single RS485 on the farthest grouped RS485 ports.
5. Connected the CAN port on the Master JK to the CAN port on the sol-ark with the proper pin,
6. Turned on Activate Battery

Once that was done, the Sol-Ark just saw it and has worked ever since. I made sure I had all the settings in place as if I was doing open loop as a precaution.

Awesome, that’s very good information and greatly, greatly appreciate it. I’m definitely gonna look into this and decide if I want to change my entire BMS set up an install JK BMS’s instead.

Where did you buy/order your JK BMS’s from?

Currently using Batrium and absolutely love it. The only drawback is I do not have the balance capacity that JK offers. Batrium is passive balance, JK’s active balance.
However, I have not really needed any balancing. Now, after several years of use, I can see a slight deviation in my batteries from initial startup. However, everything still works just fine.

I built a 12 V 4S battery set up for a chicken coop earlier this year and used a JK BMS on that setup. It runs an electric fence, automatic chicken door and two 12vdc lights.
I’m very pleased with its operation and balance feature. That was my first and so far, only JK BMS.
 
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They're built! I thought I had more terminals left to make the cables but had to order some so they're not connected yet. I'm very happy with the build quality but there was one minor with one of the circuit boards. The temp sensor threw an alarm. It turns out there was a small solder bridge on the connector. Once that was fixed the alarm was gone.
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