diy solar

diy solar

Jaibaida AP20S003S 7~20S

drbytes

New Member
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Oct 21, 2021
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113
It finally arrived.
The batteries are still on their way, is there a way to power this bms and start communicating with it ?

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Wow ..... it came with a banana too ..... LOL Sorry, but couldn't resist.

The BMS will be using the negative and one of the positive cells leads to power the BMS .... but I don't know which positive it uses.
I personally wouldn't partially connect it up without having the whole pack to connect it to .... but I am more cautious that most.

I'll be curious how this BMS works out for you .... and how much current it draws.
 
If anyone orders one and wants to know how to wire it up, I found this :

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Yeh and that's a a large banana :) So it's def. a chunker.
I chose 300A because.. well better over dimension the bms instead of having it being the weakest link.
Also.. what I read online, these are actually very decent management system, very reliable.

The instructions I found aren't actually lining up between the explanation and what is pictured.

"start wiring from the first bc0 on the right, the first wire is connected to the battery negative terminal, and the second wire is connected to the battery negative terminal, which is the first battery positive terminal and so on"

I suppose that should read :


"start wiring from the first bc0 on the right, the MASSIVE BLUE WIRE wire is connected to the overall battery negative terminal, and the first wire on the BC0 connector is connected to the FIRST CELL NEGATIVE , the second wire on the connector is connected to the first cell positive, the third wire is connected to the second cell positive and so on"

.. until you hit the 15th wire on (i guess it's called) BC1, which you combine with the 16th, 17th, 18th and 19th wire and connect it to the 14th cell positive, connect the 20th wire to the 15th cell positive and finally take the 20th and 21st wire and connect it to the 16th cell positive
 
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Thank you so much! I got one of these and of course get what you pay for (no instructions) hahaha I was just searching the internet and figuring out wiring this gives me some releif!
 
Just found this, and am looking at this exact BMS. I emailed the place, but haven't heard back about idle draw of the relay? Did you check it, and if so, would you mind giving me the numbers?

If not, is there a model number on the relay itself I might be able to look up a datasheet for?

Edit: @ jontm was able to get me the info on another thread: Kilovac EV200AAANA, per pic, datasheet and his measurements agree ~1.2W consumed by the relay.
 
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I haven't checked what the draw of it is. I tested the overcurrent, short circuit and over/under voltage and that worked as expected. Then I kicked it into production and haven't looked back.
It does have some issue tracking the SOC. It's pretty good at keeping track between 20 and 80% but anything lower than 20 or higher than 80 it's just spitballing it.
 
Oh and the description above on how to wire it is obviously for a 16 cell battery and I can confirm that works.
Before you actually start using it you might want to remove the HC05 BT module out of it and extend the wires on it so you can free it from being stuffed inside the BMS between those massive metal plates which does otherwise hurt the range.
I stood 2 meters away from this thing and the signal rating was "poor" --> no es bueno.

But I can talk RS485 to it, which sorted that out, have a look at another post I have about monitoring it.
 
Ive since ordered a second one. As a bms it's pretty good tho tracking of the SOC is not good at all. So the second one has no rs485.
In order to track the SOC (and kwhin/out) I installed a victron smartshunt, that thing seems to be pretty reliable.
 
Mine is the previous model without bt. Idle current= 0.040A at 54V. It works great.
 
Can someone post a picture using this BMS wired for 16S please? I think I understand, but a picture would be much appreciated.
 
Can someone post a picture using this BMS wired for 16S please? I think I understand, but a picture would be much appreciated.
The diagram shown in post #3 is very clear. You will end up with the first five wires of the smaller connector attached to the positive post of cell #14, and the last two (red ones) of the smaller connector both attached to the positive post of cell #16.
 
Ive since ordered a second one. As a bms it's pretty good tho tracking of the SOC is not good at all. So the second one has no rs485.
In order to track the SOC (and kwhin/out) I installed a victron smartshunt, that thing seems to be pretty reliable.
Did your second one also come with two 4 gauge wires on each post?

Both of mine (marked V1.2) came with only one 4 ga. cable on each post. My plan is to replace them with 2/0 cable. I managed to get them off despite the red loctite they used on the studs, but I broke two chip capacitors on the first try, so now I need to figure out what value they are....
 
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