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--></style></head><body lang="EN-US" link="blue" vlink="purple"><div class="WordSection1"><p class="MsoNormal">Hi Wrenches,</p><p class="MsoNormal"> </p><p class="MsoNormal">We commonly upgrade old failed out-of-warranty grid tied inverters as part of our O&M business. Anyway, we’ve been using standard transformer based isolated inverters just like the good old days. However, as the industry progresses it seems like transformer based inverters are going the way of the dodo. Does anyone know of a code compliant way to install a transformerless ungrounded inverter on an old PV array with USE-2 wire? The problem is that the modules from just a few years ago all or mostly had USE-2 and I can’t find a way to meet NEC 690.35(D)(3). </p><p class="MsoNormal"> </p><p class="MsoNormal">Best,</p><p class="MsoNormal"> </p><p class="MsoNormal">August</p><p class="MsoNormal"> </p><p class="MsoNormal">August Goers</p><p class="MsoNormal">Luminalt Energy Corporation</p><p class="MsoNormal">o:415.641.4000</p><p class="MsoNormal"><a href="mailto:august@luminalt.com">august@luminalt.com</a></p><p class="MsoNormal"> </p></div></body></html>