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Bluetooth problem

NMNeil

Solar Enthusiast
Joined
Mar 14, 2020
Messages
443
I have the overkill BMS with the Bluetooth module on both my battery banks, and they are in an outbuilding about 50 feet from the house.
Problem is that I can only get a weak signal inside my house, and it connects when it feels like it, and disconnects as quickly.
Anyone have any suggestions on how to extend the range, or replace the existing Bluetooth module with something that has a bit more power?
 
I didn't know there was such a thing.
Not sure how I'd connect it to the Overkill module though.
I may buy a spare and have a go at soldering an extension antenna to it, thanks for the ideas.
 
I didn't know there was such a thing.
Not sure how I'd connect it to the Overkill module though.
I may buy a spare and have a go at soldering an extension antenna to it, thanks for the ideas.

Well, the Overkill already has a BT module like that connected to it (at least mine does), it has maybe 6-8" of wire pigtail and a Serial/UART connector on the end where it plugs into the BMS. That's what I was referring to, is maybe you can locate the antenna on that little BT board, and see if you can disconnect the onboard one and soldier on an SMB connector or something, then can install a bigger antenna on it.

Or you could even try to lift the BT module out of where they cram it into, and get it up higher so it doesn't have any obstruction around it. And you might be able to put in one of those BT repeaters closer to the unit if needed?

I always wondered why they didn't give us ethernet modules for BMSs and not use BT, I think BT is kind of a hack for this application... I work with servers where they always have ethernet management BMCs and stuff. BT seemed like not the best idea to me since it has such a short operating distance. It would be easier to setup a wifi bridge to the shop, then have local ethernet inside the shop to plug in infrastructure.


EDIT: Oh ok, I get what you're saying now, you may buy a spare BT module so you can hack it in case you destroy it you still got the original...
 
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Extend the wire between bms and BT so you can place the BT module elsewhere

or go to RS485. With a rPI or eg ESP you can rather easily connect to wifi/ethernet

or go for an industrial RS485-to-ethernet and use the software tools

But honestly: I don't see why this would benefit. I'm not really interested in any cell voltages for daily use. Unless there is an issue the only thing which makes sense is SOC, and that's crappy on the BMSses anyway.

I would go for a seperate shunt. With eg a Victron shunt you can use VE.direct to interface with whatever you want.
 
Extend the wire between bms and BT so you can place the BT module elsewhere

or go to RS485. With a rPI or eg ESP you can rather easily connect to wifi/ethernet

or go for an industrial RS485-to-ethernet and use the software tools

But honestly: I don't see why this would benefit. I'm not really interested in any cell voltages for daily use. Unless there is an issue the only thing which makes sense is SOC, and that's crappy on the BMSses anyway.

I would go for a seperate shunt. With eg a Victron shunt you can use VE.direct to interface with whatever you want.
It would actually benefit immensely; Bluetooth,the darn thing,A L W A Y S falls short!!!(there is a 1 watt long range variety but i never saw it being used);

The cells V, and A,and direction,that is IT;
-- i too am looking for a Bluetooth Range Extender... for a while...but there is no such animal, at least i have not found one yet;
---everybody says "get a BT extender,get this,get that, here is the link", etc... just vain opinions, those are for audio,one way, they do not work ; the one we need,it does not exist,not for the BMS transmissions/ receptions that we need;
And, i think i will state this, the LiFePo4s SOC info on my bms( jk something) is just astonishingly precise; evry day, day in and day out, down to the milliVolts (always better than 0.004 V on my (voltage source compared) 20000 display count IBM/Fluke--35 years old but better than new, and i grab it when i need precision... lol) the BMS SOC thing never ceases to amaze me; i think i know how the trick is done, it takes in the volts plus the Amps in and out, and follows numerous results of lab tests, still it would take me forever and a day to do it,no need,it's been done already.
 
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