Module Addressing Failed error after adding new batteries.

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buxtonmarauder
Posts: 7
Joined: Sat Jul 20, 2024 11:05 am

I had 1 x BMS and 4 x HV25 batteries installed and all has been fine for 3 months.

FLush with the joy of "free" electricity, I bought and have now added 3 more HV25 batteries to the system this morning following (this post >> viewtopic.php?t=748)

Now when I boot the system, I get an error which (according to the manual) is a "Module Addressing Failed" error.

I set the BMS switch to 5 when adding the new batteries (n - 2 = 5)

Having googled, and found a few posts discussing the same thing, I've exhausted all the "check this" stuff (e.g. are the data cables plugged in correctly, dips all off, earther correctly)..

I didn't deplete the existing batteries down to match the SOC of the new ones - mainly cos I didn't realise that was important before I plugged em in !

I've also logged a ticket with FoxESS for support and/or an update to firmware but, as yet, no response.. the beeping is quite annoying so I figured I'd ask on here to see if it was a simple fix.

TIA for any help.

Cheers
Dave Foster
Posts: 1111
Joined: Thu Oct 13, 2022 7:21 pm

I’m hoping if you’ve been through checklists that you have checked the battery voltage and it’s now showing around 350V plus or minus a bit depending on state of charge.

But that is a comms problem - most likely one of the inter-connect cables between batteries is faulty, but also make sure that the dip switches on each battery are all set off and that the out comms port(2) of each battery goes to the in port(1) of the next battery in line.

If you have a spare cable try swapping out each of the new cables to see if you can identify which one might be faulty.

In some ways you almost want to go back to your old pack config (4 batteries) and then introduce each ‘new’ battery one at a time - you can keep the DC cables connected just remove the comms cable from the last of the old batteries to the first of the new batteries and set the rotary dip switch back to 2 - shutdown and restart your BMS

Then add each batteries comms cable individually, add one to the rotary dip switch and shutdown / restart the BMS - until you find where the fault is in the chain.
buxtonmarauder
Posts: 7
Joined: Sat Jul 20, 2024 11:05 am

That makes a lot of sense (the triage process).. Will try that tomorrow and report back. Thanks very much :-)
buxtonmarauder
Posts: 7
Joined: Sat Jul 20, 2024 11:05 am

OK.. so had a fiddle this morning...

Went back to 4 batteries and rotated the DIP (on the BMS) back to 2 - booted it all up and got the same error.

So, to try and do the isolation process properly, I'd need to revert to the minimum config which, I think is 1 x BMS and 2 * HV25 modules - correct ?

On the assumption that was correct, I isolated the first 2 modules in the stack, set the BMS DIP to Zero and rebooted resulting in the same error.. When I looked on the FoxESS app it was still showing 1 x Master and 4 x Slaves in the battery device details.

So, I'm a bit stumped now..

What's the minimum number of battery modules I need to have connected to the BMS ?

Obviously, until I can get it to boot without calling a "Module Addressing Failed" error, I don't have a baseline to work from.

TIA
Dave Foster
Posts: 1111
Joined: Thu Oct 13, 2022 7:21 pm

Minimum is 1 bms and 2 batteries, rotary dip switch set to 0

Just to confirm you are powering off and opening the isolater switch on the BMS before restarting it (it only does auto addressing at initial startup).

All the individual battery dip switches are set ‘off’ (note I have seen a battery dip switch installed upside down so check the on arrow on each)

From the BMS the comms cable is connected to the CAN-1 of the first module, then the CAN-2 is connected to the CAN-1 of the next module
buxtonmarauder
Posts: 7
Joined: Sat Jul 20, 2024 11:05 am

If you mean the switch marked "DC Switch" on this picture..

https://photos.app.goo.gl/WGjxG2NdcNh6vm8f7

..then yes

I've triple checked the DIPs on the batteries and they're all "down" with "ON" at the top of the set.

The BMS is connected from MODULE to CAN1 on battery 1 and so on.

If it makes any difference when adding the 3 new batteries I rejigged the previous batteries as follows..

Original Config.
BMS
BAT1
BAT2
BAT3
BAT4

New Config
BAT7
BAT6
BAT5
BAT4
BAT1
BAT2
BAT3
BMS

Is that going to confuse the BMS node allocation or does it wipe and re-allocate after every reboot ?

I moved the BMS to the bottom because the DC leads from the inverter would not be long enough to reach the BMS if placed it on top of the stack.

All images I've seen have the BMS sat on top of the stack but I couldn't see why that would be a problem (other than weight) ?

Thanks for your help so far. :-)
Dave Foster
Posts: 1111
Joined: Thu Oct 13, 2022 7:21 pm

Yes that’s the switch I meant.

It shouldn’t matter that the batteries are in a different order as long as it initiates the re-addressing at startup, that’s usually the rapid flashing you see when you press the BMS power button.

To keep it simple unplug the CAN-2 comms lead from battery 2 (so every battery above it is disconnected from comms) and set the rotary switch to 0 - then try starting up like that so the BMS can only see 2 batteries.

Is it possible you might have used one of the new comms leads on those lower batteries? (i’ve seen a spate of faulty ones recently)
buxtonmarauder
Posts: 7
Joined: Sat Jul 20, 2024 11:05 am

Dave Foster wrote: Sun Jul 21, 2024 3:41 pm Is it possible you might have used one of the new comms leads on those lower batteries? (i’ve seen a spate of faulty ones recently)
Yep... most definitely..

I'm comfortable making my own cables (CAT6 RJ45 etc) so I could make some as an isolator/alternate..

According to this https://github.com/nathanmarlor/foxess_ ... Guidelines it's a single pair connection ?

Unless you have a source for appropriate cables that isn't FoxEss ?

Cheers
Dave Foster
Posts: 1111
Joined: Thu Oct 13, 2022 7:21 pm

For RS485 alone it would be a single pair, but there are other signals in there (Canbus, Power, Gnd and an Inverter connected).

This cable is a through cat5/6 cable with all 8 cores passed straight through pin for pin - so if you have a couple of cat5/6 cables around you could eliminate the inter-connects.
buxtonmarauder
Posts: 7
Joined: Sat Jul 20, 2024 11:05 am

OK.. changed the first two comms cables for CAT5 straight-throughs and it made no difference..

Here's a video of the booting process if that helps..

https://photos.app.goo.gl/fD3iEAUYLq4fjVFbA

and an image of the version nums from the inverter..

https://photos.app.goo.gl/cPEZrbmTJaFjC1jS9

TIA
Dave Foster
Posts: 1111
Joined: Thu Oct 13, 2022 7:21 pm

It's very strange (and I imagine equally frustrating), the slow flashing green 'run' light tells you that the BMS is in boot mode and so is effectively going through it's re-addressing - it looks ok to start but then it starts to error - i'm starting to wonder if Fox have made a recent change in the startup behaviour and it's using the battery voltage to scan 7 batteries instead of reading the rotary switch.

I think the best thing to do now is to re-connect all the comms cables on all batteries, set the rotary dip switch to 5 and then if you could video the start up - but sufficient wide angle for me to see all of the batteries as it starts up.

In theory Fox should be able to get BMS logs which will tell you which module is failing and you'll need all batteries attached for them to determine that - but i'm hoping at startup we might be able to work out after x polls of the batteries before it flashes red to identify which module is the problem.
buxtonmarauder
Posts: 7
Joined: Sat Jul 20, 2024 11:05 am

It annoys me when people ask a question on forums, followed by a flurry of responses and then nothing... because they have solved their problem but not then come back to the forum to explain what the problem was and the subsequent solution.

So here I am, a little later than planned but here nevertheless.

The solution to my problems turned out to be firmware mismatches.

Got my sparky to ring up FoxEss (they wouldn't talk to me) who walked through some diagnostics with an engineer on a video chat. Engineer then remotely upgraded the firmware on the inverter and all the batteries. Once that was done, and the whole thing rebooted it was all working.

All the original cables were retained and no duds were found. So it was firmware all along.

What I don't understand is this, if the inverter is online (and it knows what firmware is in the batteries too) why can't the firmware be updated automatically ? I asked this of the FoxEss engineer and he said it can *only* be triggered remotely by FoxEss. Just seems weird to me..

Thanks @dave foster for your help earlier :-)

Cheers.
Dave Foster
Posts: 1111
Joined: Thu Oct 13, 2022 7:21 pm

Great, glad you got it sorted.

that's a new one to add to the list - mismatched firmware, i've seen it cause instability before but from this it would appear on the HV25's (which share a V2 platform firmware) that it simply doesn't work.

The firmware has to be pushed out by either an installer or Fox themselves (which they are very good at doing when contacted), but we have asked that they add a 'request' firmware upgrade button to the app so you can request it yourself.
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