<div dir="ltr">The inverter produces acceptable noise under no-load and at loads above 50 W or so.<div>The noise (humming/buzzing) increases drastically at low power. So, essentially it makes a lot of noise at night.</div><div>Has anyone else encountered this? We suspect it is the transformer vibrating - some kind of resonance with the inverter enclosure. But it's the first time we have encountered this.<br><div><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><span><p style="padding:5px 0px;color:rgb(36,105,100);font-size:14px;font-family:soleil,Helvetica,Arial,sans-serif;line-height:1.4rem;letter-spacing:0.04rem;font-weight:lighter!important"><img src="https://viridianenergy.ca/sites/all/themes/viridian/emails/signature-line.png" style="color:rgb(0,0,0);font-family:"Times New Roman";font-size:medium;letter-spacing:normal"><br style="color:rgb(0,0,0);font-family:"Times New Roman";font-size:medium;letter-spacing:normal"></p><p style="padding:5px 0px;color:rgb(36,105,100);font-size:14px;font-family:soleil,Helvetica,Arial,sans-serif;line-height:1.4rem;letter-spacing:0.04rem;font-weight:lighter!important"><strong><span style="font-size:1.2rem">Eric Smiley,</span></strong> Project Manager<br><a href="mailto:eric@vecoop.ca" style="color:rgb(255,255,255)" target="_blank"><span style="color:rgb(0,168,133)">eric@vecoop.ca</span></a><br><a href="tel:+12507036004" style="color:rgb(255,255,255)" target="_blank"><span style="color:rgb(36,105,100)">T: 250.703.6004</span></a><br><a href="tel:+18883860116" style="color:rgb(255,255,255)" target="_blank"><span style="color:rgb(36,105,100)">T: 888.386.0116</span></a><br><strong><a href="https://viridianenergy.ca/" style="color:rgb(255,255,255)" target="_blank"><span style="color:rgb(0,168,133)">VIRIDIANENERGY.CA</span></a><strong></strong></strong></p><p style="padding:5px 0px;color:rgb(36,105,100);font-size:14px;font-family:soleil,Helvetica,Arial,sans-serif;line-height:1.4rem;letter-spacing:0.04rem;font-weight:lighter!important"><strong style="color:rgb(0,0,0);font-family:"Times New Roman";font-size:medium;letter-spacing:normal"><strong><a href="https://viridianenergy.ca/" target="_blank"><img src="https://viridianenergy.ca/sites/all/themes/viridian/emails/signature-footer.png"></a></strong></strong><br></p></span></div></div></div></div></div></div></div></div></div></div>