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<DIV dir=ltr align=left><SPAN class=312173504-19102010><FONT color=#0000ff
size=2 face=Arial>Thanks for the info Dan and boB.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=312173504-19102010><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=312173504-19102010><FONT color=#0000ff
size=2 face=Arial>What production tests required to maintain listing? Do you
happen to know if there is a different regimen for micro vs string vs central
inverters? </FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=312173504-19102010><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=312173504-19102010><FONT color=#0000ff
size=2 face=Arial>I'm working on developing a detailed commissioning
procedure. Detailed yet generic. There will be at least two versions for
inverters. One for string and one for central. In my book, central inverters
have re-combiners (standalone or integral) and string inverters don't.
</FONT></SPAN><SPAN class=312173504-19102010><FONT color=#0000ff size=2
face=Arial>I'm trying to understand which functions are tested in the factory on
every unit so I can avoid unnecessary duplication by the commissioning
people.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=312173504-19102010><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=312173504-19102010><FONT color=#0000ff
size=2 face=Arial>Thanks in advance for any light you can shed on the
subject!</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=312173504-19102010><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><STRONG><I><SPAN
style="FONT-FAMILY: 'Monotype Corsiva'; mso-bidi-font-family: Tahoma">Matt
Lafferty</SPAN></I></STRONG></DIV>
<DIV dir=ltr lang=en-us class=OutlookMessageHeader align=left>
<HR tabIndex=-1>
<FONT size=2 face=Tahoma><B>From:</B> re-wrenches-bounces@lists.re-wrenches.org
[mailto:re-wrenches-bounces@lists.re-wrenches.org] <B>On Behalf Of
</B>Exeltech<BR><B>Sent:</B> Monday, October 11, 2010 10:04 AM<BR><B>To:</B>
RE-wrenches<BR><B>Subject:</B> Re: [RE-wrenches] Inverter 1741 Listing
Process<BR></FONT><BR></DIV>
<DIV></DIV>
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<TD vAlign=top>Matt,<BR><BR>The 5-minute delay is verified in the group of
inverters sent to the test laboratory. Then, as long as the software
and hardware don't change, it's presumed the delay in all production units
meets the value(s) measured in the tested units.<BR><BR>An alteration in
either hardware OR software can result in a unit being required to
completely re-test (as Bob pointed out). NRTLs get copies of the
source code and can and do periodically compare their copy as submitted
with the original test units to the software being programmed into the
inverters during production to verify it's the same.<BR><BR>NRTLs conduct
unannounced "field audits" by simply showing up on site and randomly
selecting various aspects of the product for verification -- including the
software.<BR><BR>The overall UL1741 certification process is extremely
complex, very time consuming, and quite
expensive.<BR><BR><BR>Dan<BR><BR><BR><BR>--- On <B>Fri, 10/8/10, boB
Gudgel <I><boB@midnitesolar.com></I></B> wrote:<BR>
<BLOCKQUOTE
style="BORDER-LEFT: rgb(16,16,255) 2px solid; PADDING-LEFT: 5px; MARGIN-LEFT: 5px"><BR>From:
boB Gudgel <boB@midnitesolar.com><BR>Subject: Re: [RE-wrenches]
Inverter 1741 Listing Process<BR>To: gilligan06@gmail.com, "RE-wrenches"
<re-wrenches@lists.re-wrenches.org><BR>Date: Friday, October 8,
2010, 9:26 PM<BR><BR>
<DIV id=yiv1780317400>On 10/8/2010 6:04 PM, Matt Lafferty wrote:
<BLOCKQUOTE type="cite">
<DIV><SPAN class=yiv1780317400078505600-09102010><FONT size=2
face=Arial>Hola Wrenches,</FONT></SPAN></DIV>
<DIV><SPAN class=yiv1780317400078505600-09102010></SPAN> </DIV>
<DIV><SPAN class=yiv1780317400078505600-09102010><FONT size=2
face=Arial>Does anybody know off the top of their head if the
<EM>"5-minute-wait-to-interconnect"</EM> function is tested on 100% of
inverters produced? <EM>(i.e. every single inverter is tested
with AC & DC within the start parameters of the unit for at least
5 minutes)</EM></FONT></SPAN></DIV>
<DIV><SPAN class=yiv1780317400078505600-09102010></SPAN> </DIV>
<DIV><SPAN class=yiv1780317400078505600-09102010><FONT size=2
face=Arial>Thanks!</FONT></SPAN></DIV>
<DIV><SPAN class=yiv1780317400078505600-09102010></SPAN> </DIV>
<DIV><SPAN class=yiv1780317400078505600-09102010><FONT size=2
face=Arial>Matt Lafferty</FONT></SPAN></DIV></BLOCKQUOTE><BR>Good
question. I bet it's not 100% tested because if the software does
not<BR>change, then they may just not wait the extra 5 minutes in order
to save money on testing.<BR><BR>Or, maybe they do a random sampling for
this test.<BR><BR>Theoretically, it shouldn't matter as long as the
software does not change<BR>and the hardware is tested enough in other
ways, like, timers and clocks etc.<BR><BR>BTW, Nowadays, there are two
options for manufacturers of grid interactive inverters....<BR><BR>And
the UL spec has gotten more stringent.<BR><BR>One option is that
you have to have the code (software) blessed by the NRTL in
a separate process (another UL specification, (UL 1998 –Software in
Programmable Components")<BR><BR>OR, if they don't go for that option,
then if software changes need to be done to the inverter, the inverter
must (technically) go through the UL1741 listing process all over
again.<BR><BR>boB</DIV></BLOCKQUOTE></TD></TR></TBODY></TABLE><BR></BODY></HTML>