Let me put it another way. I started off with a 3Kw Inverter, it worked but just wasn't quite enough, ended up with a 4kw Samlex EVO-4024. Just normal average use (me sitting here typing on PC, Radiant heating is running atm I'm drawing 11.5A off my battery banks. Add coffee maker @ 80A, add 1200W Inverter Microwave, another 80A... All of a sudden the water pump kicks on whoops another 60A. Now add in more "life" as in kids, spouse using things and guess what... 3Kw isn't as much as one thought.
Keep in mind if you are faced with an Inverter Upgrade later, it will often mean changing wires, fuses/breakers and such which adds up. As a result I used to suggest that if you figure you "need" 3Kw you more than likely will want 4Kw and likely that should be the initial target, the Next Step up from what anyone thinks they need. Guess what, people would dump on me for that suggestion... I have BTDT myself and so have numerous others but folks don't want to hear it.
MPP Solar / Growatt and similar IAO's. They all do exactly what they are supposed to. Like everything else, there is lower end "Value" product to Tier-1 level Quality product. Q-Cells for example also has a full on AIO system even with Battery Storage, as do many other companies... These are NOT COVERED BY WILL OR THIS FORUM mostly because they are mostly sold in Europe or Asia (Not USA or Canada, which is a terrible loss IMO). They "May look identical" but these systems are not, the format (casing, displays etc) are similar in appearance but internally not so much. These units are actually Modular internally and the various sub-sections are replaceable / serviceable. Warranties reflect the quality of the products (first hint at better quality is the documentation to start with). The Internals are what matters and the higher quality products have better guts and better programming capabilities.
The key is to get the right one for your usage today & future usage that would allow for easy upgrades later if needed. Stackable is always a good thing as things do change down the road, regardless if we can see it coming or not. The devil is in the details and that really has to be looked at when comparing makes & models, for example a GroWatt will come with more standard features but does cost a bit more...
Lessons Learned:
When I got started Victron was not available to buy in Canada at the time... I am using a Midnite Classic-200 SCC & a Samlex EVO-4024, all good Tier-1 Quality gear and does what it is supposed to as it should. Had I been building TODAY, I'd go with an all out Victron System because of the quality, integration and manageability & capabilities in that regards. I would use this if I was going with a "composite system", second choice would be GroWatt (not MPP) as Growatt is a larger more established company and they have a HIgh Spec for the componentry within the box. Don't get me wrong, the Samlex & Midnite stuff is great but managing different hardware with different protocols / software and such is a "challenge" and therefore a PITA worthy of avoiding.
BUT IT'S VOLTRONIX... They are an OEM that makes components for many VARS (Value Added Resellers) who have their own specifications & requirements. Are they the Sub-Contracting OEM making the gear for GroWatt, it is quite possible but the only way to know for sure is to dissect the equipmet down to the boards and compare them down to the chips used. Schneider, EP-Ever, Yiyen, Sigineer, CyberPower, Solis and many more have AIO's... it all depends on what your wallet will allow for.
Hope it helps, Good Luck.
