<html>
<body>
The plan is to use N/C relays. As this is in a backup system, N/O relays
would need to spend most of their lives energized. The relays will not be
able to receive any control power while the grid is up.<br><br>
If all else fails and the relays stay closed and overcharge the
batteries, the high voltage disconnect of the Magnum inverter should shut
the system down before it becomes hazardous.<br><br>
Drake <br><br>
At 07:53 AM 8/29/2017, you wrote:<br>
<blockquote type=cite class=cite cite="">My vote would still be to use
two single pole relays as suggested previously to kill each leg. That way
you build in redundancy and dropping either leg will do the trick. In
fact, it sounds like this would be even better than a two pole relay for
the redundancy reason.<br><br>
The other factor is whether you are using NO or NC relays. My engineer
requires NO relays in these cases so they would fail in the open position
only. I'm not sure how this would work, or if it would work with solid
state relays. I have never dug into this. My understanding is that solid
state relays fail in the closed condition (shorted). This would preclude
their use in a situation where opening the circuit is the preferred
failure mode. Maybe someone with some more knowledge in this area can
chime in on whether SSRs are a good idea in this scenario.<br><br>
Jason Szumlanski<br><br>
<br>
On Mon, Aug 28, 2017 at 10:19 PM, Nick Soleil
<<a href="mailto:nsoleil@enphaseenergy.com">
nsoleil@enphaseenergy.com</a>> wrote:<br>
<dl>
<dd>The one-pole relay will work for de-energizing any of the Enphase
microinverters.<br><br>
<dd>Nick Soleil <br>
<dd>Field Application Engineer<br>
<dd>Enphase Energy<br>
<dd>Cell: <a href="tel:(707)%20321-2937">707-321-2937</a><br><br>
<dd>On Aug 28, 2017, at 6:03 PM, Drake
<<a href="mailto:drake.chamberlin@redwoodalliance.org">
drake.chamberlin@redwoodalliance.org</a>> wrote:<br><br>
<blockquote type=cite class=cite cite="">
<dd>Hi Nick,<br><br>
<dd>I should mention that the inverters being AC coupled are M-250s, not
the new IQ series. Would that make any difference?<br><br>
<dd>Thanks,<br><br>
<br>
<dd>Drake <br><br>
<br>
<dd>At 03:12 PM 8/28/2017, Drake wrote:<br>
<blockquote type=cite class=cite cite="">
<dd>Hi Nick,<br><br>
<br>
<dd>At 11:20 AM 8/28/2017, you wrote:<br>
<blockquote type=cite class=cite cite="">
<dd>Content-Language: en-US<br>
<dd>Content-Type: multipart/alternative;<br>
<dd>Â Â Â Â Â Â Â Â
boundary="_000_56449940CA694DDAABB811FCC45A2070enphaseenergycom_"<br>
<br>
<dd>You can use a one-pole relay. We show one-pole switching in
our zero-export, self-consumption doc for PEL applications.<br><br>
<dd>Nick Soleil <br>
<dd>Field Application Engineer<br>
<dd>Enphase Energy<br>
<dd>Cell: <a href="tel:(707)%20321-2937">707-321-2937</a><br><br>
<dd>On Aug 28, 2017, at 6:44 AM, Drake
<<a href="mailto:drake.chamberlin@redwoodalliance.org">
drake.chamberlin@redwoodalliance.org</a>> wrote:<br><br>
<blockquote type=cite class=cite cite="">
<dd>Hello Wrenches,<br><br>
<dd>I am going to AC couple some Enphase inverters and found some really
nice solid state, single pole relays to control them with. Enphase says I
must use 2 pole relays for the control current even though the
disconnects will turn off all power for maintenance. <br><br>
<dd>Enphase claims that the inverters will not shut down reliably with
only one line opened. This does not make sense to me in view of UL 1741.
Is Enphase correct in their claim, or are there other reasons that both
poles need to be opened <br><br>
<dd>I want to use the solid state relays because the coil voltage is
between 3 and 32 volts. This would avoid the need to add voltage dropping
series resistors to protect the coil for higher battery
voltages.<br><br>
<dd>Alternatively, does anyone know of reasonably priced, 2 pole solid
state relays?<br><br>
<dd>Thanks,<br><br>
<dd>Drake <br><br>
<dd>Â <br>
<dd>Drake Chamberlin<br>
<dd>Athens Electric LLC<br>
<dd>OH License 44810<br>
<dd>CO License 3773<br>
<dd>NABCEP Certified Solar PV <br>
<dd><a href="tel:(740)%20448-7328">740-448-7328</a><br><br>
</i>
<dd>_______________________________________________<br>
<dd>List sponsored by Redwood Alliance<br><br>
<dd>List Address:
<a href="mailto:RE-wrenches@lists.re-wrenches.org">
RE-wrenches@lists.re-wrenches.org</a><br><br>
<dd>Change listserver email address & settings:<br>
<dd>
<a href="https://mailtrack.io/trace/link/3edab27b5ab293b8ed7e9b72f6b21719374c3d42?url=http%3A%2F%2Flists.re-wrenches.org%2Foptions.cgi%2Fre-wrenches-re-wrenches.org&userId=1613865&signature=4d8b59c3f4041e3e">
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a>
<br><br>
<dd>List-Archive:
<a href="https://mailtrack.io/trace/link/46525d1ae98ac2c9b206af627e181a5e7abef1f9?url=http%3A%2F%2Fwww.mail-archive.com%2Fre-wrenches%40lists.re-wrenches.org%2Fmaillist.html&userId=1613865&signature=f1379328237c52bb">
http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html</a>
<br>
<br>
<dd>List rules & etiquette:<br>
<dd>
<a href="https://mailtrack.io/trace/link/37c2fa3cce2cec32c9af29b35805b1166887102d?url=http%3A%2F%2Fwww.re-wrenches.org%2Fetiquette.htm&userId=1613865&signature=f5a9d67705ba6495">
www.re-wrenches.org/etiquette.htm</a><br><br>
<dd>Check out or update participant bios:<br>
<dd>
<a href="https://mailtrack.io/trace/link/42b8962882456a240060cea7f870a550cf549bc6?url=http%3A%2F%2Fwww.members.re-wrenches.org&userId=1613865&signature=8682c7a34db623bd">
www.members.re-wrenches.org</a></blockquote>
<dd>_______________________________________________<br>
<dd>List sponsored by Redwood Alliance<br><br>
<dd>List Address:
<a href="mailto:RE-wrenches@lists.re-wrenches.org">
RE-wrenches@lists.re-wrenches.org</a><br><br>
<dd>Change listserver email address & settings:<br>
<dd>
<a href="https://mailtrack.io/trace/link/3edab27b5ab293b8ed7e9b72f6b21719374c3d42?url=http%3A%2F%2Flists.re-wrenches.org%2Foptions.cgi%2Fre-wrenches-re-wrenches.org&userId=1613865&signature=4d8b59c3f4041e3e">
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a>
<br><br>
<dd>List-Archive:
<a href="https://mailtrack.io/trace/link/46525d1ae98ac2c9b206af627e181a5e7abef1f9?url=http%3A%2F%2Fwww.mail-archive.com%2Fre-wrenches%40lists.re-wrenches.org%2Fmaillist.html&userId=1613865&signature=f1379328237c52bb">
http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html</a>
<br><br>
<dd>List rules & etiquette:<br>
<dd>
<a href="https://mailtrack.io/trace/link/37c2fa3cce2cec32c9af29b35805b1166887102d?url=http%3A%2F%2Fwww.re-wrenches.org%2Fetiquette.htm&userId=1613865&signature=f5a9d67705ba6495">
www.re-wrenches.org/etiquette.htm</a><br><br>
<dd>Check out or update participant bios:<br>
<dd>
<a href="https://mailtrack.io/trace/link/9b840d0d9b3573fe10be9ca23650f9910436d5fb?url=http%3A%2F%2Fwww.members.re-wrenches.org%2F&userId=1613865&signature=125e41a41f5138ad">
www.members.re-wrenches.org</a></blockquote>
<dd>_______________________________________________<br>
<dd>List sponsored by Redwood Alliance<br><br>
<dd>List Address:
<a href="mailto:RE-wrenches@lists.re-wrenches.org">
RE-wrenches@lists.re-wrenches.org</a><br><br>
<dd>Change listserver email address & settings:<br>
<dd>
<a href="https://mailtrack.io/trace/link/3edab27b5ab293b8ed7e9b72f6b21719374c3d42?url=http%3A%2F%2Flists.re-wrenches.org%2Foptions.cgi%2Fre-wrenches-re-wrenches.org&userId=1613865&signature=4d8b59c3f4041e3e">
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a>
<br><br>
<dd>List-Archive:
<a href="https://mailtrack.io/trace/link/46525d1ae98ac2c9b206af627e181a5e7abef1f9?url=http%3A%2F%2Fwww.mail-archive.com%2Fre-wrenches%40lists.re-wrenches.org%2Fmaillist.html&userId=1613865&signature=f1379328237c52bb">
http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html</a>
<br><br>
<dd>List rules & etiquette:<br>
<dd>
<a href="https://mailtrack.io/trace/link/37c2fa3cce2cec32c9af29b35805b1166887102d?url=http%3A%2F%2Fwww.re-wrenches.org%2Fetiquette.htm&userId=1613865&signature=f5a9d67705ba6495">
www.re-wrenches.org/etiquette.htm</a><br><br>
<dd>Check out or update participant bios:<br>
<dd>
<a href="https://mailtrack.io/trace/link/9b840d0d9b3573fe10be9ca23650f9910436d5fb?url=http%3A%2F%2Fwww.members.re-wrenches.org%2F&userId=1613865&signature=125e41a41f5138ad">
www.members.re-wrenches.org</a></blockquote>
<dd>_______________________________________________<br>
<dd>List sponsored by Redwood Alliance<br><br>
<dd>List Address:
<a href="mailto:RE-wrenches@lists.re-wrenches.org">
RE-wrenches@lists.re-wrenches.org</a><br><br>
<dd>Change listserver email address & settings:<br>
<dd>
<a href="https://mailtrack.io/trace/link/3edab27b5ab293b8ed7e9b72f6b21719374c3d42?url=http%3A%2F%2Flists.re-wrenches.org%2Foptions.cgi%2Fre-wrenches-re-wrenches.org&userId=1613865&signature=4d8b59c3f4041e3e">
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a>
<br><br>
<dd>List-Archive:
<a href="https://mailtrack.io/trace/link/46525d1ae98ac2c9b206af627e181a5e7abef1f9?url=http%3A%2F%2Fwww.mail-archive.com%2Fre-wrenches%40lists.re-wrenches.org%2Fmaillist.html&userId=1613865&signature=f1379328237c52bb">
http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html</a>
<br><br>
<dd>List rules & etiquette:<br>
<dd>
<a href="https://mailtrack.io/trace/link/e5dd443e106ab9262a64531e245e33cacc6439c3?url=http%3A%2F%2Fwww.re-wrenches.org%2Fetiquette.htm&userId=1613865&signature=1ff02acb7afaa5ce">
www.re-wrenches.org/etiquette.htm</a><br><br>
<dd>Check out or update participant bios:<br>
<dd>
<a href="https://mailtrack.io/trace/link/df1a46cc62f80e77abb320b6b58d2daa1df33313?url=http%3A%2F%2Fwww.members.re-wrenches.org&userId=1613865&signature=5658938ab50f2b2d">
www.members.re-wrenches.org</a><br>
</blockquote><br>
<dd>_______________________________________________<br>
<dd>List sponsored by Redwood Alliance<br><br>
<dd>List Address:
<a href="mailto:RE-wrenches@lists.re-wrenches.org">
RE-wrenches@lists.re-wrenches.org</a><br><br>
<dd>Change listserver email address & settings:<br>
<dd>
<a href="https://mailtrack.io/trace/link/d637b44281f438904170f585d45de0c029d858d0?url=http%3A%2F%2Flists.re-wrenches.org%2Foptions.cgi%2Fre-wrenches-re-wrenches.org&userId=1613865&signature=4e891bb2cdab5fbc">
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a>
<br><br>
<dd>List-Archive:
<a href="https://mailtrack.io/trace/link/e6c3b50ab784871396cf8aa61952a354fd078c8c?url=http%3A%2F%2Fwww.mail-archive.com%2Fre-wrenches%40lists.re-wrenches.org%2Fmaillist.html&userId=1613865&signature=5c6459243bdea642">
http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html</a>
<br><br>
<dd>List rules & etiquette:<br>
<dd>
<a href="https://mailtrack.io/trace/link/e5dd443e106ab9262a64531e245e33cacc6439c3?url=http%3A%2F%2Fwww.re-wrenches.org%2Fetiquette.htm&userId=1613865&signature=1ff02acb7afaa5ce">
www.re-wrenches.org/etiquette.htm</a><br><br>
<dd>Check out or update participant bios:<br>
<dd>
<a href="https://mailtrack.io/trace/link/df1a46cc62f80e77abb320b6b58d2daa1df33313?url=http%3A%2F%2Fwww.members.re-wrenches.org&userId=1613865&signature=5658938ab50f2b2d">
www.members.re-wrenches.org</a><br><br>
<br>
</dl><br>
_______________________________________________<br>
List sponsored by Redwood Alliance<br><br>
List Address: RE-wrenches@lists.re-wrenches.org<br><br>
Change listserver email address & settings:<br>
<a href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org" eudora="autourl">
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a>
<br><br>
List-Archive:
<a href="http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html" eudora="autourl">
http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html</a>
<br><br>
List rules & etiquette:<br>
<a href="http://www.re-wrenches.org/etiquette.htm" eudora="autourl">
www.re-wrenches.org/etiquette.htm</a><br><br>
Check out or update participant bios:<br>
<a href="http://www.members.re-wrenches.org/" eudora="autourl">
www.members.re-wrenches.org</a></blockquote></body>
</html>