Hello,
Because some of you encountered connection issues between SUN2000L / SUN2000-L1 & SUN2000-M0 inverters and your Wi-Fi routers, we decided to share with you the supported Wi-Fi connection and the encryption modes, as follow:
SUN2000L (2-5KTL): - WLAN (IEEE 802.11 b/g/n, 2.4 GHz) & the WPA, WPA2, or WPA/WPA2 encryption mode is recommended for routers;
SUN2000 (2-6KTL)-L1: - WLAN (IEEE 802.11 b/g/n, 2.4 GHz) & the WPA, WPA2, or WPA/WPA2 encryption mode is recommended for routers;
SUN2000 (3-20KTL)-M0: - WLAN 802.11b, 802.11g, 802.11n (2.412 GHz to 2.484 GHz) & the WPA, WPA2, WPA/WPA2 encryption mode is recommended for routers;
As a conclusion, if you have Wi-Fi routers with dual mode (2.4GHz and 5GHz), you have to let them work in both frequencies or to enable the 2.4GHz band only for the connection with the inverter. The 5GHz routers are not supported yet by Huawei inverters.
If you ecounter any kind of problem, don't hesitate to contact us at eu_inverter_support@huawei.com . Is better to contact us directly when you are next to inverter in order to check locally the settings of inverter.
Also, you may call out hotline numbers:
Kind regards! 
