How does Victron bluetooth work?

[RayF]

Yes I programmed it about a year ago and it works fine, I'm just trying to add an extra line to it to display battery temperature now I've replaced the AGM with Lithium.

Okay, my apologies, I hadn’t realised and I know nothing about that. I was assuming it was all plug and play components that I’m used to. Hopefully someone who knows more can advise you

 

[andys]

Okay, my apologies, I hadn’t realised and I know nothing about that. I was assuming it was all plug and play components that I’m used to. Hopefully someone who knows more can advise you

No apology needed for trying to help

 

[dav1d]

@andys, looking at the VE.Direct protocol document, the temperature field (T) is only transmitted from BMV-7xx devices, not MPPT devices. I’ve only got a BMV, not a MPPT so can’t test this myself.

Have you tried monitoring the raw VE.Direct output to see if the field is there? E.g. just printing the VE.Direct data on a serial debug output on your computer?

Would also be worth looking on the Victron community forum, but from the document it looks like it’s not possible.

 

[T6Jay]

I agree with dav1d.

Connect your laptop via usb/serial adaptor directly to the MPPT serial port. Open up a serial terminal of some kind (I use the arduino ide one sometimes). Check for a line starting with a 'T'. If it's not there, no amount of arduino programming will read it.

 

[T6Jay]

As you'll notice though, it's not displaying a value even though I'm reading "T" which is the label used for temperature.

Do you mean the arduino can see a 'T' incoming? How do you know?

The MPPT says it's receiving Battery Temperature via the bluetooth network but it's not passing it on through the serial port.

How do you know this? did you check all the serial traffic on a terminal?

 

[andys]

Yes that's exactly what I did first thing this morning. Monitoring the data coming out of the VE port, the label "T" and associated data is not there. So the MPPT can read the temperature data and display it on the app, but it doesn't pass the data through unfortunately, so that's the end of that.
Just a bit annoying as, although I saw when I first set this up that it didn't read the temperature and output it, I thought if it was fed the extra data from another sensor that it would be available to everything else on the network.

Went to get a tree and then used the van to drive to work for the afternoon. During the drive discovered that I'd disturbed the amp wiring so the passenger seat has to come out again

 

[T6Jay]

Sorry I misunderstood, I thought you were looking for arduino help.

It looks like the victron VE wireless can have multiple clients. I wonder if it's possible to have the arduino read the bluetooth data from it?

 

[andys]

Sorry I misunderstood, I thought you were looking for arduino help.

It looks like the victron VE wireless can have multiple clients. I wonder if it's possible to have the arduino read the bluetooth data from it?

Yes we're back to the black art of Victron bluetooth. Shame they're so open about their wired protocol but their bluetooth seems to be locked down to their apps/hardware only.