Solar Panel Expansion onto existing system

[williebreedt]

Good day everyone,

I'm looking to get some inputs to see how I am able to add more solar panels to my existing system. My current system looks as follows:

Inverter: Growatt - SPF 5000TL HVM-P
Maximum PV Array Power : 4500W
MPPT Range @ Operating Voltage: 60VDC ~ 115VDC
Maximum PV Array Open Circuit Voltage: 145VDC

Battery : Pylontech 3.5Kwh

PV Combiner Box: 4 Input to 1 Output
With regards to the panel configuration, In total I have 6 panels installed (2 strings of 3 panels). A String consists of:
1 X 365W Canadian Solar Kumax (CS3U-365P-F35)
2 X 335W Canadian Solar (CS6U-335P-F35-MC4)

What I just need some help with is to understand what I can do to come as close as possible to the inverter charging capacity without running the risk of frying the inverter.

Would really appreciate any help - also happy to add some more context if required.

 

[rodrick]

As long as you do not exceed the max voltage of 145 with any strings you will be ok try to find the same panels you are using or another panel with the same specs as the ones you have try to get each string at the same voltage and amperage and then you could run 4 strings

 

[williebreedt]

As long as you do not exceed the max voltage of 145 with any strings you will be ok try to find the same panels you are using or another panel with the same specs as the ones you have try to get each string at the same voltage and amperage and then you could run 4 strings

Hey Rodrick,

Trying to find these panels from my known suppliers - might have to look at others..

I was quietly hoping that I might be able to use fewer panels with higher outputs to reduce the overall costs and real estate requirements, that's probably not going to be possible?
i.e. instead of 2 x 3 Panels - go with 2 x 2 Panels of 550W as an example.... the strings might be a bit unbalanced like this.

 

[rodrick]

Solar panels have a certain amount of power they can generate per square meter so your not going to save any real-estate unless you go to a bifacial panel

there are several threads on this site about mixing panels on the same mppt sometimes adding a panel can cost you more power output and reduce your overall output you may want to use blocking diodes to help this problem I recommend you do some research before getting more panels

 

[williebreedt]

Solar panels have a certain amount of power they can generate per square meter so your not going to save any real-estate unless you go to a bifacial panel

there are several threads on this site about mixing panels on the same mppt sometimes adding a panel can cost you more power output and reduce your overall output you may want to use blocking diodes to help this problem I recommend you do some research before getting more panels

Agreed - that's why I'm trying some forums as someone might just have encountered something similar. In hindsight - I should have spent a bit more and went for a different Inverter or at least one that allows for High voltage strings. This specific one is causing a bit admin to find the right balance using panels with lower wattages.

 

[rodrick]

Another option is adding another scc and set up a separate array on that scc which will give you some redundancy