Hello everybody!
I read through multiple articles and also Victron's documentation about cable length, but I am still not 100% sure, so I decided you bother you here with my questions :-)
I use a setup with 3x Multiplus II, 3x Skylla-i Chargers, 2x MPPT, 4x SmartLithium. Everything by Victron.
Everything (except the batteries) is connected to a generic bus bar and then connected to a Lynx BMS + Lynx Distributor. The batteries are connected to "the other" side of the Lynx distributor - all in parallel.
CerboGX:
I am using a CerboGX for managing everything. Everything is connected together. In the "System Setup" I use as "battery monitor" the "Lynx BMS". In "DVCC" I set "SVS - Shared voltage sense" to "Forced on". My idea behind that the voltage at the BMS is the "real" voltage that all the devices (Multiplus, MPPT, Skylla-i) should adjust to.
Batteries:
All batteries have the same cable length (plus and minus). Each of them are connected to the Lynx Distributor. I think this is okay, since the cable length is as it should be.
Multiplus:
I currently use a parallel single phase system, but will change it to a three phase system soon. However, they are running as one "cluster". Currently I have the same cable length, but it is pretty messy. I only have about 0.5 meters of length. The cables have 50 mm².
Question #1: Is it possible to have different plus and minus cable lengths between the Multiplus? Example: MP 1: 0.3m, MP 2: 0.5m, MP 3: 0.7m
Question #2: Is it possible to have different length of plus and minus cable? For example: plus cable: 0.5m and minus 0.7m?
Skylla-i:
The Skylla-i chargers are connected to a small busbar and then connected via a 2.5m cable to the "central" busbar. The three Skylla-i also run in a parallel cluster.
More or less I have the same questions as for the Multiplus, but the main question is: I have a way longer cable to the central busbar, than the Multiplus. More or less the Multiplus and the Skylla show the same battery voltage.
General question:
I currently also have the issue, that the Skylla-i is not charging, when the Multiplus is charging. Right now the Multiplus is Inverting and the Skylla is in Storage mode. I would like them to work in parallel mode. Is this because they see a slightly different voltage?
Sorry for that long explaination and thank you in advance for your ideas/experiences!
Best regards
Alex