question

Please post the configuration settings of the two controllers.

hi

RS 450/100

Firmware is 1.05

Network Control

cant see the Networked Operation as there is no Menupoint in the cerbo

(shouldnt there be a menu like for the 250/60 with Networked Operation where i can see the status? its the first VE Can device i use)

MPPT 250/60

Firmware is 1.59

Charge Voltage 52,40V

Charge Current 17.6A

(the third controller has a charge limit of 16.1A so still 16.3A chargelimit left for the 450/100)

Both Controllers are Nework Controlled (BMS Controled from Pylontec Batterys)

SOC of the Batterys is 40%

Charge/Discharge limit set from BMS 50A

for me it looks more like a mppt tracking issue

the voltage of the array in the 450/100 is way higer then it should.

the 250/60 150v (4 in a row)

the 450/100 180v (4 in a row)

all same pannels

@stemue

The voltage start and operating range of the 450/100 and the 250 are vastly different.

The 250 will start tracking from 5v above the battery. The 450 will not do this, it is designed for high string voltages.

The 450 will only start operating at 120v and can use the range 80v to 400v. But the algorithm is also affected by battery voltage. See the tech spec section of the manual.

So what I am really saying is you need a higher string voltage to make the 450 work better. Take your 2x4 and make it 1x8 if it meets the requirements with voc and battery float and you should have a banging system there. It is being wasted with a 4x1 string and the 4x2 string.

allready did the change to 1x8 as i thought the same but it didnt work well wich takes me to the point i am now to test. even if the 450/100 is for higher voltage range it should work ok at 160v mppt and 200v oc on a string. for shure it does but the Pylontech are 15s lifepo4 so voltage is 45v to 52,5 as in the pylontech specs. so we are in the range of the specs on both sides on the battery voltage and the PV voltage or do i miss something ? at the time of the screenshot the battery voltage was at 49.5v

@Alexandra

I am wondering why the Rs450 ist not working fine with 1*8 modules. This should be a Voc of around 320V or more for STC? For a 450V MPPT this should be perfect?

Or let me ask in a different way, what ist the best performance range of the RS450 in terms of Voc and Vmpp for 54V float?

TIA

Hi,

it looks like the RS450/100 has some software issues.

MPPT Tracking is not working that good. MPPT working voltage is 10% higher then it should be. You loose 10%+ of the power you get on optimal MPPT tracking. Shadow management is not working well. So i opened this thread to give Victron a hint that there is a problem. At moment i would not buy this device again and would better use 2 60/250 if possible even if you dont need shadow management and would 2 strings in parallel on the 60/250. Maybe Victron is able to solve this issues with future softupdates. But for now its that way in my perspective.

I'm just thinking about buying the rs450 / 200 for a configuration with 1 x 9 modules each mppt and Voc around 400 V. If I'm right this would be in the optimum tracking range for the rs450.

Reading the thread, I am quite confused after all. Even the operation with 1 x 8 modules does not seem to deliver the optimum (see above). I would be grateful for further comments from Victron.