[RE-wrenches] SMA Tripower

[August Goers]

I checked the math and it indeed seems like a rounding issue – 20,000 W /
480 V / √3 = 24.05626122 A



I wonder if the SMA tech support agent that Brian spoke with was just
reading the manual when they said it was 24.1 A. Regardless, it seems like
we would need to rely on the manufacturer to clarify their intent when the
nameplate and manuals don’t match up. I had been taught to rely on the
nameplate right on the device when all else fails.



Hopefully no one has a situation where this actually matters!



August

Luminalt



*From:* RE-wrenches [mailto:re-wrenches-bounces at lists.re-wrenches.org] *On
Behalf Of *Garrison Riegel
*Sent:* Thursday, September 01, 2016 6:39 AM
*To:* RE-wrenches
*Subject:* Re: [RE-wrenches] SMA Tripower



Hi Brian,



Can we not invoke Art. 220.5(B) Fractions of an Ampere to round down to a
30A OCPD in this case?



I suppose that .1 could be pretty significant when combining many of these
inverters.



Garrison Riegel

Solar Service Inc


On Aug 31, 2016, at 11:24 PM, Brian Mehalic <brian at solarenergy.org> wrote:

Hey Wrenches-

Just a heads up on the SMA Tripower - I like the inverter, but you gotta
read the install manual!



Spec sheet says 24 A continuous output current for the 20 kW Tripower.
Install manual (and tech support) says 24.1.  That  extra .1 A takes you
from a 30 A to a 35 A breaker.



Of course you should follow the install manual not the specs.  But what
about the label on the side of the inverter?  Well I've seen more than a
handful that are labeled with a flat-out 24 Aac output current.  What's an
installer or inspector to do besides hope mfg's can get their numbers in
order?



Upon closer examination, most of the STPs are 0.1 A higher than their spec
sheet per the install manual - it doesn't really make a difference on the
12 or 15 kW models - just the 20 where you have to go up 1 standard OCPD
size.  Pretty sure there's lots of 20 kW units out there backfeeding a 30 A
breaker.  Hmmmmm....



Brian Mehalic
NABCEP Certified Solar PV Installation Professional™ R031508-59

520.204.6639



Solar Energy International
http://www.solarenergy.org



SEI Professional Services

http://www.seisolarpros.com



_______________________________________________
List sponsored by Redwood Alliance

List Address: RE-wrenches at lists.re-wrenches.org

Change listserver email address & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org

List-Archive:
http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html

List rules & etiquette:
www.re-wrenches.org/etiquette.htm

Check out or update participant bios:
www.members.re-wrenches.org
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20160902/b0a2b86c/attachment-0002.html>