I would like someone from Victron to answer my question on the above title. I Like Victron equipment in general as the feedback via remote console & VRM is far superior to any other product I have tried. Over the past several years I have spent considerable money switching to a complete Victron setup. My RS 450/100 is the latest addition.
But, why on earth would Victron release a controller RS 450 series that DERATES the charging current severely once the voltage rises above 57V ??? I have a 48V traction FLA deep cycle battery which requires a 60V absorption charge. Whilst the RS 450 is in Bulk mode with the voltage well below 57V I see around 3000W on each tracker (100A total) but the moment the voltage approaches & exceeds 57V the charging current is SEVERELY throttled down. By the time the battery voltage reaches the actual absorption point (this morning that is 61V as the battery is quite cold) the charge current produced by the RS 450 is only about 1200W on each tracker. THAT IS A LOSS OF 60% !!! This means the absorption set point takes much longer to reach due to the throttling down of the charge current whilst stll supposedly bulk charging.
I find this problem unacceptable. I have been trying to figure out why they would release such a product then I see that the charging routine on their Lithium 48V batteries is around 56 - 57V so, is this a ploy to coherse everyone to purchase VERY EXPENSIVE Lithium batteries ??? those of us who choose to remain with a much cheaper 'proven' technology like FLA get a controller that simply will not charge these batteries as it should. There is absolutely no mention of the 57V derate in any of the manuals for the RS 450 series (unless it has been added recently) or I would have seen it before my purchase. What Next?? will we see firmware updates on other controllers that will also derate them above 57V... it could be happening already I do not know. Personally, I only bought the HV controller because my latest arrays are 60 meters away from the control room so a higher voltage controller seemed the right choice... how wrong I was, the RS 450 sucks!!
I hope Victron is listening to these posts you should not be manipulating software in your products to coherse people in to buying only a certain type of very expensive battery. For example my FLA 48v 1000AH battery cost me 5K Euro brand new and will last 10+ years cycling 70 - 80% SOC daily. An equivalent Victron Lithium battery 600AH cost 30K Euro and will last ?? years cycling 20 - 80% SOC daily. I bet the unknown figure for the Lithium is not x6 longer as is the cost comparison - even if it were true, a battery that lasts 60+ years is a pontless investment for a retired electrical engineer at 60 years old, even if I had the money.
Please Victron fix this issue quickly it can be done with a simple firmware update. It doesn't matter which battery type I choose in the settings menu the same derate occurs, this is ludicrous and a huge waste of 10 KW PV potential.