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If it is visible, it’ll be on the end on that temp probe and outside of the nice metal box.
No, need to open.

Just a wire coming out of the enclosure.

I thought that is what it might look like.
It will be a pair of wires with a thermistor on the far end, but may indeed appear as a single wire.

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Mine is 2 wire

Methinks, if I talk to them again, is to ask for the same length external NTC wire, as what the balancing wires are, and see what they say.

Re.extending the balancing wires, I have tried before to extend them with thicker wires at the end, the thin ones close to the plug, short as is comfortable.

These temp sensors are for the cells. Just stick them on the cells with tape.
You set the BMS temp limits in the bluetooth app and the BMS will then decide.
I just publish the temp values the the GX and you can look at them in VRM, but only the BMS does something with that data. It’s used the same way as the min/max cell voltages.

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Tried that logic, if you are using the same supplier as me, no joy.

Now this is where I would be careful, this doesn’t follow the same argument as the temperature probes. Here you could cause problems.
This is where you want mV accuracy, and for that small resistance changes can make the difference.
Let’s look at it in a bit more detail. These BMS’s won’t be individually calibrated, what they will have is a standard calibration for 0.4m cables or 0.8m cables or whatever they sell as standard.
If I want 3m cables I will have to use the app and re-calibrate.
How would I do that?
I’d bolt all the +'s together and then all the -'s together, apply a known exact 3.3V to them all simultaneously, and then go into the app and adjust all the readings to 3.3V.
Easy enough, but once done those cables stay 3m long.
This is fine and this will be the basis of why they sell standard cable lengths from the factory.

Now if you shorten some cables, put joint resistances and extra lengths in other.
You are adjusting things by an extra quarter of an ohm in a wire where only a quarter of an ohm existed. This is not the same thing at all as adding a quarter of an ohm to an existing 50kohm wire like with the temperature probe.

If you want to do this make your individually spec’d cables and then re-calibrate as a I described above.

I tried … and chucked the project even before connecting anything.
Thank snot I did … cause now I know why NOT! :laughing:

Info embedded for the future.

I don’t know this to be true, a good design would be agnostic to cable distance because the input impedance was extremely high. Although at times those wires take 260mA, and that means at other times that circuit is around 12 ohms. This may or may not throw things a wobbler, but as you say that’s all things that happen in the “nice metal box”.

What I do note is they take two discrete wires to the same battery terminal. (The positive of one cell connected by a thick copper busbar to negative on the next cell is electrically really the same place).
If the volt drop didn’t bother the BMS they would only take one wire. So obviously the volt drop does bother the BMS when one cell is balancing and the adjacent cell is not.
So it’s very sensitive.

So don’t think about just taking one wire and then just splitting into two inputs at the BMS end.

Here, hold my beer … :laughing:

I REALLY like that saying. Anyone who knows me in person would agree with me being like that … T&C’s apply obviously! My battery box proof of my wife’s perspective.

I will try … If I get it right, awesome. Will ask for exact details before the time.

My motto: Asking is free (hold my beer) … so is the No.

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@Phil.g00 the pic you asked for?

Remove the glue and the cable unplugs, it appears.

Re. the temp discussion. Don’t know why the differ …

Main screen:

Active BMS temp sensors, one external:

Options to switch on in the software:

Venus Temp sensor:

Inverter battery temp - presume it is same as Venus but I did have both connected:

Venus BMS Temp:

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I inquired about the price of 3m long balance leads.
I have to order a batch of 50.
My inquiry was for sufficient leads for 50 BMS’s, there are two leads/BMS, so I don’t know if this is for 100 actual leads or for 50 leads.
I am going to pass on this anyway so I am not going to inquire more, because it takes 2 days for this rep to respond.
Anyway for what its worth, here is what I was told: 50 @1.92$ each = $96

Go similar replies. Who did you speak to?

Ms F. Xiao

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Ek werk met selle dame. :raised_hand: :+1:

The importer for the BMS’s, found out he was talking direct to her too, so I took “over” the talks on what we want to order, so he can relax and just pay her, as I already paid him.

Ordering these for the Venus connection, having added a RS485 port extra:

For these BMS’s that already has a UART/Bluetooth connection:

The JBD-AP20S003’s, comes with a enclosure and can do 24v and 48v, are simply out of stock.
So therefor we opted for the JBD-AP20S004, seeing as they do have stock now.

Cause methinks this semiconductor shortage is going to cause even more drama going forward, so waiting longer is not an option.

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We paid same, also airfreight, just 13 x JBD-AP20S004 and 1 x 24v 100amp BMS.

Titbit: The VAT and import duties gets added to the $ price paid, for those who don’t know.

The next cell order, we can import the BMS’s with the cells. Amy can arrange that she said.

Am seriously considering that option, as then the BMS’s become SO much cheaper.

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Well, I fully intend to be in on the next order and I don’t really need the BMS’s before I have the cells, and I also have to take the BMS’s to South Africa. I already have other gear up to my eyeballs to take.
If you are going to include BMS’s in your next order I don’t think I am going to order them separately now. I’d rather get them sent straight to SA.

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If you need a address in SA, you can use mine?