I am a long time user of Schneider products and I need to build an AC coupled system for battery back up with 400Ah of 48V Gel batteries. Schneider used to sell a 3kW string inverter, but it was never as nice a machine as the XW battery inverter line. I'd like to use a high-quality transformer less string inverter for my PV array, but I have only seen SMA Sunny Boys connected to SMA Sunny Islands. Can I mix the two brands, or will there be a WWII style conflict between them?
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9 years 5 months ago
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Martha,
In this case, France and Germany are true allies. Not only can you mix the brands, but you can still set the SMA TL inverter to back-up mode using the on board rotary switches (inverter cannot have been run for more than 10 hours) and it will power ramp down in response to the XW frequency shifting as the batteries reach full charge. You need to set Rotary switch A to "D" and Rotary switch B to "0" (Zero). This puts the TL into Island Mode with a wider frequency window and it will respond to frequency changes from the XW by ramping power down as the XW approaches 62Hz. This is, of course, in violation of the UL 1741 listing - but, since the SMA TL US is connected to the grid THROUGH the XW, it is not connected directly to the grid and the XW becomes the UL device. For more detail, please refer to the TL US install manual section 7.1.1, page 47.