Time for a new Warpinverter build

Author	Message
rogerdw Guru Joined: 22/10/2019 Location: Australia Posts: 955	Posted: 11:27am 15 Feb 2021         Clockmanfr said   rogerdw, I have not built a 'Warpspeed Inverter' yet.  I am watching you with great interest.  I just do the OzInverters. Gulp, the pressure's on. Haha.   Quote   AC COUPLING , or Back charging the batteries I have not used a HF, High Frequency,  GTI because second hand old heavy toroidal types are easily obtainable and very cheap, plus you get to use the GTI internal MPPT .   'Oztules' and others have experimented with HF types and do not find any real difficulties. I have always seen AC coupling as the way forward, rather than just DC and many expensive charge controllers. I had read that you were keen on the older LF inverters and I wondered which were the ones with toroidal transformers, other than our much loved AeroSharps. I believe older 'Inspire' units did ...  and seeing your pix here of the Sunny Boy SMA units, I assume they also use toroids. Have spent a lot of time looking for technical details of them, but haven't been able to find any internal pictures below their circuit boards. Can you give me some model numbers of LF inverters so I can keep my eyes open. I understand any SMA inverter with 'TL' in the model number stands for 'transformerless', so I know to avoid them. I actually picked up a faulty 5kW TL SMA a few weeks ago for $25 and (as a long time elect tech) was actually quite impressed with the build quality and mechanical design. No idea if they are actually any good, but I like how they are built. There was also an SMA 10kW Tripower unit there for $25, but they are 3 phase and it was big  ...  and I had a car full of AeroSharps already.     Quote   I originally bought a very expensive, so called Rolls Royce of commercial Inverters, 48vdc to 240vac  ... Yes, sounded like quite a saga. I have spent a lot of time over on the fieldlines forum reading up on all the background  ...  been quite a journey for all you guys.   Quote   The above are a cost effective and very reliable system, A is used most and C is my guaranteed safety system. Where i do not have access to the GTI internals, then i use B.   For a 19kW Array I prefer using 2off 1.7kW & 4off 2.5kW GTI's for 14kW, and using DC Charge controllers for the 5kW as these can gently finish charging that precious 48vdc battery bank. I trust this information helps. Haha, you're answering questions I was going to ask somewhere in the future once I'd made some progress on my build  ...  but seeing you've mentioned it  ... I see you're using the old GTI's to provide power  ...  effectively seperate solar systems on your seperate houses  ...  but using the output from your Ozinverter as your own mini-grid for them all  ... ...  so I'm assuming you still have to have some conventional charge controllers charging the Ozinverter's battery bank? Anyway, thank you very much for all your detail, I hope I can retain enough to make the right choices once I reach that stage.