I recall reading something about this on the forum, but my search-foo is letting me down.
TLDR: How to swap the sign on the current being reported by the BMS
I have a customer who purchased a SunVolt LiFePO4 battery, these apparently support CAN, and are the flotsam from the shipwreck that was SolarZero in NZ. There are a number of these batteries on TradeMe at the moment, i think usually found on grid-tied systems (as was SolarZero’s primary market).
The customer has been very resourceful, and found that a Victron to Dyness cable (the type where pins 4,5 go to pins 7,8) works, but only with CAN terminators in place. As an aside; We always use the terminators as per the manual, but find that Dyness work without them, as do our own RoarPower batteries, but we always install the terminator. So i suspect that the BMS doesn’t do software termination, but that’s fine.
The primary problem:
The battery is reporting the charge or discharge current, with the wrong sign. So when the battery is discharging, the GX / VRM / etc shows charging, and vice versa.
I’m hoping @lxonline or @nickdb or @alexpescaru will remember the hack that can fix this.
To be clear; the battery has other issues too, such as reporting that there are 1 batteries online, and 26,742 offline, and i’m pretty confident that it doesn’t meet the Victron CAN standard, but the customer would be happy to just get the charge/discharge sorted.
My memory says that someone wrote a custom driver and dropped that into the GX?
Thanks team.