Mark,
There are many inverters that do not have a neutral-just not many single-phase inverters. Since all inverters must have at least an equipment ground, the phases can be compared with ground. The testing standard covers what is required. If neutral-ground bond is lost, it will show up in a bad voltage phase-to-ground. Since utility-interactive (U-I) inverters just inject current when the utility voltage is in proper range, our inverters do not produce a separate voltage. The only problems that our inverters can cause is a slightly raised voltage due to current flow at the point of connection. Also, a much less likely but current concern in Hawaii is temporary overvoltage. As the utility voltage goes to zero in an outage, a U-I inverter must quickly clamp its current or the voltage at the inverter terminals (and potentially the house service) could momentarily go above nominal voltage. Generally, this is not a problem since an inverter that does not act quickly enough will damage itself. Bill. Bill Brooks, PE Principal Brooks Engineering 3949 Joslin Lane Vacaville, CA 95688 707-332-0761 (office and mobile) b...@brooksolar.com (email) www.brooksolar.com (web) From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Mark Frye Sent: Thursday, December 19, 2013 8:10 AM To: RE-wrenches Subject: [RE-wrenches] SB 240 - No Neutral Sense Conductor Folks, I was looking at the SMA micro inverter and notice only connections for L1, L2 and earth. I thought all grid tied inverters needed a neutral sense conductor to monitor for phase loss. Any ideas? Mark Frye --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com
_______________________________________________ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
