Almost every ESS battery compatibility page notes that old VE.CAN BlueSolar (150/85 & 150/70) with the rectangular metal case does NOT support external BMSes, because the firmware does not implement the required control instructions.
On the face of it, this makes sense.
However, after a couple of years of this being the case, WHY has the feature not been implemented?
I currently have some of these devices, and they are essentially useless now.
I understand that firmware "space" might be an issue to add this feature, but would it not be possible to build a cut-down firmware that contains ONLY this feature and none of the standalone charging features? That way a "BMS-compatible" firmware can be flashed, since none of the other features matter then.
It really is a shame that these excellent chargers have basically been abandoned now, especially since they were marketed as the top-of-range models initially.