Hiya, sorry if this has been answered before. i have a small pv system which is only 2.7 kw however by invertor can handle 3.5. is there a max pv input for the ac coupled. as i was thinking of adding an extra sting with just 2 panels
thanks in advance
The AC coupled PV is irellevant. It will just take upto 3kw from the available power, anything extra will go to your home, or exported. I have 8kw in various arrays with my AC3, in summer it can get a bit silly, so we have iBoost aswell to use the excess
If your PV inverter can take the extra couple of panels, then go ahead and add them, will help you generate a bit extra
L174945 You might want to check that the two panels in series can reach the lower voltage threshold to start generation on that string. If the maximum panel voltage is 50V, that'll potentially give you 100V, but if the inverter needs 120V to draw current, you'll never get any energy from the string, whatever the state of the sun. Just need to match string voltage and inverter input voltage.
Hi Tim i have the solis Solis s6-gr1p2.5 k it says start-up voltage of 60 volts and i am thinking of using the same brand that's already up Trina TSM-DE09.05. which have a max power of 33.8 and open circuit voltage of 40. so im guessing the max would only be 67volts which is just over the start-up. would that mean i would need to add 3.
thanks in advance Ian
L174945 If your existing array is on one string and there's room on that roof, it might make sense to add the panels to the existing roof and either lengthen the existing string, or split the string into two; the inverter appears to have two MPPTs.
The issue with adding more panels to an existing string is that during the summer, it's feasible that the inverter will not be able to handle the full output and will clip the PV to the maximum the inverter can handle. The advantage of so many panels on one string is that the PV voltage will reach the inverter threshold earlier in the day and earlier in the year and will maintain output until later in the day and later in the year. The downside would be if the string voltage exceeded the inverter maximum at summer peak; if so splitting onto two strings would be needed, losing the advantage of longer generation days and season.
Whether additional panels are added to an existing string or the array is split into two strings is a balance of what you want: higher peak output or longer harvesting period. The orientation of your roof will be a factor. Speak to your installer for detailed advice.
thanks so much everybody i am going to upgrade to a 5k hybrid as well soon but at least i know for now i wont fry my AC Coupled invertor.
L174945 That is a big change as both your PV inverter and AC3 will be replaced? Is that needed? Feels expensive for the gain.
THALL agree... If it isn't broken...
Just for extra options, because I have done this recently and still looking to expand more. GivEnergy are releasing a EMS device for multiple inverters to function correctly, as in multiple AC3's if you require more battery input/output. Also the AC3 can monitor 2 seperate PV systems. I have this. 6.6kw on my East roof on a Solis 8kw inverter and 4.6kw on a Solis 5kw inverter on my West roof.
I have 1x AC3 with 1x 8.2 and 9.5 battery attached. As soon as the EMS unit arrives which is apparently Q2 this year I will add a second AC3 to give me 6kw charge discharge.