<html>

<body>

Hi boB,<br><br>

Would there be any issues with delayed control of the microinverters? We

do  plan to  use disconnects for maintenance.<br><br>

Thanks,<br><br>

Drake <br><br>

At 06:27 PM 8/29/2017, you wrote:<br>

<blockquote type=cite class=cite cite="">Content-Type:

multipart/alternative;<br>

 boundary="------------155C815B9802686293824DDD"<br>

Content-Language: en-US<br><br>

<br>

SSRs, especially AC SSRs made from thyrisotrs (scrs and/or triacs)Ā 

are "leaky" in general<br><br>

so when turned OFF, can cause a shock....Ā  Maybe not enough to kill

you but maybe enough<br><br>

to make you fall off the roof !<br><br>

I'm not sure why the disconnects aren't good enough which should already

be in place ?<br><br>

boB<br><br>

On 8/29/2017 4:53 AM, Jason Szumlanski 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:%28707%29%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>Ā Ā Ā Ā Ā Ā Ā Ā 

boundary="_000_56449940CA694DDAABB811FCC45A2070enphaseenergycom_"<br>

<br>

<dd>You can use a one-pole relay.Ā  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:%28707%29%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>Ā <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:%28740%29%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>

<br><br>

<pre>_______________________________________________

List sponsored by Redwood Alliance

List Address:

<a href="mailto:RE-wrenches@lists.re-wrenches.org">

RE-wrenches@lists.re-wrenches.org</a>

Change listserver email address & settings:

<a href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org">

http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a>

List-Archive:

<a href="http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html">

http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html</a>

List rules & etiquette:

<a href="http://www.re-wrenches.org/etiquette.htm">

www.re-wrenches.org/etiquette.htm</a>

Check out or update participant bios:

<a href="http://www.members.re-wrenches.org">

www.members.re-wrenches.org</a>

</pre><font face="Courier New, Courier"></font></blockquote><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>