Sunny boy 3300

[Kgh1977]

Hi all. 

I've been given a sunny boy 3300 inverter & 2 24v 250w mono panels.

I'd like to bench test the inverter but the manual points to a min DC input of 200v.

I know the 2 panels alone are way below the required amount, but was hoping that 24/48v may enable me to view the display. 

I have no previous experience with solar & would greatly appreciate any help.

:signthankspin:

 

[binky]

Dig out the manual on-line, there's usually an option to have display ON but without DC, sometimes listed as night-time mode. AC will fire up from cold, but without DC is does tend to shut down again.

 

[Kgh1977]

Thanks for the info lads.

Think I'm gonna need a different inverter. Wanted an off grid install

Any recommendations for off grid inverters?

 

[Kgh1977]

Thanks canoeboy

I'll take a look

 

[Kgh1977]

Hi guys

Connected ac side of inverter to supply & powered up....nowt.

Tested for voltage on inside of inverter and 240 there.

Waited for a bit but nothing.

Can't see any switches that would cut power if lid is removed.

Do I also need a dc supply?

 

[JDiP]

I have the same issue with my sb3300. Nothing happens when I plug in ac power but if I connect 70v dc to the over side I get all three lights coming on and staying on. It might be that the electronics are run from the dc side and the capacitors are used to store some power to run the system during night time. I can find nothing on any forums to confirm this so any help appreciated.

 

[JDiP]

If the system genuinely runs of dc side then it would seem to be suitable for off grid providing you don’t draw more ac then it provides. That probably means lots of panels.

I currently have two large Pannel’s rated at about 35v and 350w each so I’m limited to what I can pump into it. There’s very little discussions on the minimum dc supply but would seem to be around 200v

 

[binky]

If the system genuinely runs of dc side then it would seem to be suitable for off grid providing you don’t draw more ac then it provides. That probably means lots of panels.

I currently have two large Pannel’s rated at about 35v and 350w each so I’m limited to what I can pump into it. There’s very little discussions on the minimum dc supply but would seem to be around 200v

this thread is from 2016  so the original poster is no doubt long gone. 

That inverter is 'grid tied' and won't work off-grid. Min DC voltage required to get the system working will be stated in the tech manual for the inverter, but is usually around 70-90V so your 2 panels might just about get it going on a good day. It really is far too big for 2 panels, you would be far better off with a smaller unit, or connect a lot more panels. If you want to use your panels off-grid to say, charge batteries, you can get some cheap units off Amazon. Look for solar charge controllers, ideally with an MPPT for greater peformance. 

Either way, inverters tend not to respond to anything unless there is AC and DC present, they shut down into a sleep-mode to reduce energy wastage, otherwise they would be pulling leccy from the grid, which you would be paying for. In sleep mode they only use somthing like 15 Watts. They do use DC voltage to power themselves, hence you can have a failed grid connection, ie no AC available, but the inverter will be in standby mode. In standby mode they will 'wake up' at a lower voltage than that needed to actually generate any useable power, that way they are primed and ready to go when the irradiance gets stronger , ie the sun comes up. Hence your inverter lights up with AC and panels connected. Being grid tied does mean your inverter will not output any power without  mains AC connection - it's a safety feature for DNO workers.