ETL listed 250W Micro grid tie solar inverter mppt pure sine wave DC20-50V to AC 240V (SUN250G-US)

Update: both inverters have stopped working as of november 2018. The first one died a few months after purchasing, 3 red blinks and no output to grid. After several emails to seller, the factory was supposed to send me a label and address to return and no responses, seller went quiet. The second one died a month or so ago and i just verified it is dead, same issue as the other one. Very dissapointed. Will see if they honor the warranty. This inverter works! I bought (2) a month a part from each other. Not quite sure about the efficiency yet, have 4 325 watt modules hooked up to each it and generally have 800 or so ac watts measured at solar noon per inverter. They connect together easily enough, but the Weiland connectors are near impossible to source in less than 100 qty, so to wire into the breaker I had to pull the connector off and set to the side. There is no installation manual for this inverter on the mfg site : chinesegrid.com, however the etl and Tuv certification documentation is easily downloaded and is legit. I tried contacting the seller for instructions as well as emailing the certified technical person on the website and the etl cert for a manual and additional information on the energy management device pictured in the manual for the 500 watt smaller version for monitoring energy of the inverters and still have not received a reply. The inverter does take longer than described to start producing power average time of 3:40 after attaching to US AC 240v. Overall, very happy with the build quality and packaging directly from China. Both inverters arrived in good order about a month after order and we're trouble free to setup. I wish I had more information about the inverters antenna port and what I can do to monitor the inverter directly and independently of each other. I currently am reading my meter with a rainforest zigbee reader and hall effect sensors on the inverter ac lines. It has done what I intended which was to offset my pool pump and spa filtration during the day. On the weekend I can charge my electric car with nothing else in the house running and have 500 watt draw from the grid on level 1 charging. One more inverter and 4 more modules I could charge my car for free!! So far generated 150kwh which at my day average energy rate totals just under $40 of energy saved in a month. You don't need all the modules to be hooked up to have it work either. And mppt works well and is fun to watch when you plug in a module and monitor the DC current and voltage with a current shunt meter. Definitely better than my purple units retired with this one, and no fans to drive you crazy. I may buy another one if I can get more information on what I can do with these units for monitoring and controlling the inverters remotely.