<div dir="ltr"><div>There is some scuttle about just installing regular non-isolated (transformerless) inverters with old SunPower positive grounded mods and setting the expectation with clients that there may be some losses due to PID. But, overall having a new inverter that is likely to be more reliable with monitoring might be worth it. I had heard that PID losses can be as much as 50% but I think that might be some of the very oldest SunPower mods dating back to the early 2000s. By the time 2012 rolled around, maybe the PID issue was almost gone anyway, just speculation. </div><div><br></div><div>I can't say we've done this yet except for a couple of Enphase projects with old SunPower mods. So far so good.</div><div><br></div><div>Best,</div><div><br></div><div>August</div><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div dir="ltr"><div dir="ltr"><p><br></p></div></div></div></div></div><br></div><br><div class="gmail_quote gmail_quote_container"><div dir="ltr" class="gmail_attr">On Wed, Aug 27, 2025 at 12:43 PM Richard Scott via RE-wrenches <<a href="mailto:re-wrenches@lists.re-wrenches.org">re-wrenches@lists.re-wrenches.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div>You Love Solar sells SMA SB6000U capable of positive ground systems.</div><div><a href="https://youlovesolar.com/collections/inverters/products/sunny-boy-6000us-1" target="_blank">https://youlovesolar.com/collections/inverters/products/sunny-boy-6000us-1</a></div><div><a href="https://youlovesolar.com/pages/switching-from-negative-to-positing-grounding-for-older-sunpower-systems" target="_blank">https://youlovesolar.com/pages/switching-from-negative-to-positing-grounding-for-older-sunpower-systems</a></div><div>You might try calling to see if they still do repairs.</div><div><br></div><div>Richard</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Aug 27, 2025 at 11:54 AM Travis Knipple via RE-wrenches <<a href="mailto:re-wrenches@lists.re-wrenches.org" target="_blank">re-wrenches@lists.re-wrenches.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div>Hi all,<br>I'm trying to retrofit an old SMA/Sunpower system with a + grounded Array.<br>What options are out there for a new string inverter to put in these systems (if any)?<br>Thanks,</div><div><br></div><span class="gmail_signature_prefix">-- </span><br><div dir="ltr" class="gmail_signature"><div dir="ltr">Travis Knipple<div>Senior Engineer</div><div>Hudson Solar Solutions LLC</div><div>Rhinebeck, NY 12572</div><div>518-539-8040 x408 | <a href="mailto:travis@hudsonsolarsolutions.com" target="_blank">travis@hudsonsolarsolutions.com</a></div><div><br></div><div><img src="https://ci3.googleusercontent.com/mail-sig/AIorK4wuT0Jf3z34mlt7_aUK-QOs2RIbM5kO1oBpUVNKSFuc5ADydVvuRPMkmhWoT1Bglre_AATVNHA1BkN_" width="96" height="75"></div><div>PVIP# PV-111821-013612</div></div></div></div>
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