VE Bus BMS Mk2 is no longer being found and so our Multiplus also no longer appears. I have disconnected the multiplus from the BMS module and connected it to the cerbo GX. Then disconencted the BMS module fom the cerbo GX.
Using Mk3 interface connected to the multiplus, turned off the ‘connection to VE Bus’. This config allowed the multiplus to function again and also show up on both remote and local displays, obviously with no BMS this was just a sanity check and not a fix.
This problem occured around the same time that the cerbo firmware was upgraded along with the VE Bus MK2 BMS. I have put the cerbo back to formal release 3.54 and multiplus is version 508 to see if I can clear the error code15 but no luck.
Ok. Have you tried to shut everything down and bring it all back online in sequence?
Try step through all the inverter and GX settings just to be sure nothing was lost.
Failing that, double check nothing else might have happened, like a loose connection etc.
Yes, tried re-start in squence several times and no luck. All wiring is fine and the LAN interconnection cables have been tested with a LAN indicator and all good.
Inverter settings on the ‘charger page’ of ‘VE CONNECT’ program are set for’Lithium Batteries’ , ‘LiFePo4’ and ‘configured for VE Bus BMS’ with various voltages set for the 24V batteries we use. No assistant is used because its VE Bus and in any event it warns that it is not required.
Under the ‘Usage’ page I have that set to ‘Do not use VS’
From my understanding because the BMS is connected directly to the cerbo GX and the multiplus is connected to the BMS via the mains detect controller if the BMS has an issue then the cerbo GX will not see it or/and the multiplus, which is the result I am getting. However because the Cerbo GX is connected directly to the BMS then if the BMS was ok it would appear in both the local and remote displays?
So next question is can the BMS V2 firmware be uploaded directly into it in case its corrupt using just the MK2 or MK3 interface and say VE Flash? According to Victron the latest firmware for the BMS is:- v113 – 13 October 2022
Managed to get the multiplus and BMS V2 back in the ‘firmware update’ list by re-flashing the BMS via the multiplus with firmware 1146113. The multiplus is running 2612552. Unfortunatly still no luck with error code 15.
If I put the multiplus in ‘stand alone mode’ it works fine so assume that the BMS is faulty.
Its quite frustrating and did not see these issues with the previous BMS so think simplest solution is replace the BMS V2 with the old one. Progress, hmm …
Still agonising over this and hate to admit defeat so had another go today. Put the multiplus firmware back to its original ‘out of the box’ version 2612490 and again reflashed the BMS Mk2 with 1146113 through the multiplus as directed.
With multiplus connected direct to VE bus on cerbo, BMS mk2 disconnected and settings made on the multiplus using VEConfig but ensuring that the ‘BMS VE control’ is disabled. The multiplus appeared on VEConnect with no error and inverter mode or charge mode could be selected.
Changing the wiring to accomodate the BMS Mk2 as described by Victron and error 15 appeared after couple of minutes and the multiplus and BMS Mk2 was no longer present when the - Device - Firmware was selected.
So disconnecting the multiplus from the BMS MK2 and connecting it directly to the cerbo GX VE port resulted in them both appearing again in the Device-Firmware scan. Firmware update to version 556 was suggested so allowed the update but it made difference and still had error 15,
You have removed the MK3 and ONLY the bms and multi is connected to the ve.bus? Is the cerbo powered direct from the battery? How long is the rj45 cable between the bms and multiplus as it should be kept as short as possible.
With the Multiplus connected to the BMS Mk2 and then the BMS connected to the Cerbo GX neither are ‘seen’ in the firmware update list.
With the Multiplus connected to VE Bus port 1 and the BMS Mk2 to VE Bus port 2 and I know this is not correct both are ‘seen’ in the firmware update list but still error 15.
Network cable length is approx 500mm from the multiplus to BMS and BMS to Cerbo GX approx 300mm so would assume no ‘refelections’ would be seen due to low data rate.
My conclusion is that some data from the multiplus to BMS or vice versa is conflicting when directly connected together?
