Inverter protection [RE-wrenches]

Mon Dec 11 19:49:22 EST 2000

Questions and answers below.

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From: 	William Miller[SMTP:wrmiller at slonet.org]
Reply To: 	RE-wrenches at topica.com
Sent: 	Monday, December 11, 2000 6:01 PM
To: 	RE-wrenches at topica.com
Subject: 	Re: Inverter protection [RE-wrenches]

Pals:

This query brings up a number of issues for me:

1. This group is for experienced installers sharing info to better
themselves (or something like that).  I did not recognize the name of the
gentleman inquiring, but maybe he should hire an experienced installer?

Doug is with SunnySide Solar in Southern VT (Richard Gottlieb and Carol 
Levin). SunnySide is one of the true old-time pioneers in the business, 
dating back at least 12 - 15 years. They may not know everything, but 
they've done, and still do, an awful lot.

7. I have never had my hands on a Trace Power Panel (IPPS) but I have
reviewed the drawings, and I see some possible shortcomings:  I'm not sure
where one connects a grid input.  Has anyone done this?  Is it safe to
bypass the AC input to one inverter and not the other (which is possible
with the separate transfer switches)?  I do not like to plumb to an SW
inverter via the end panel KOs since this obscures the AC connections as
well as the relay and temperature sensor connections, however this is done
in the IPPS.  Also, I would not relish handling the weight of an IPPS.

Generally speaking, since each installation has its own unique
requirements, an IPPS can not be guaranteed to fit all needs.  I prefer to
custom build to satisfy these unique needs.

We use the Power Panels a lot. Like anything else, they need to be "gotten 
used to". A talented person can build a nicer, friendlier, roomier power 
system, but not for anywhere near the same cost. We very successfully use 
them to make cost effective systems. You've got to know how far to go with 
them. We sometimes add junction boxes for combining, metering, etc, outside 
the DC 250, but for a typcial system around here, there is plenty of space.

Either AC grid OR generator power is connected to the "Bypass switch" box 
above the inverter. If BOTH grid and gen are needed, then one is hooked up 
to the Bypass switch (usually grid) and the other is hooked into the 
(admitedly difficult to access) end panel connections.

The weight is pretty easy. For a while we were unmounting the inverter, 
which defeats a lot of the convenience of the PP. Now we either screw a 2 x 
4 to the wall as a ledger, or use our battery moving box as a temporary 
rest. Even the largest PP can be readily moved by two people. I have 
mounted a small one alone. Not preferable, but possible.

Jeff

Jeffery D. Wolfe, P.E.
Global Resource Options, LLP
A Woman-Owned Vermont Limited Liability Partnership
4 Kibling Hill Road
P.O. Box 51
Strafford, VT 05072
802/765-4632
802/765-9983 (Fax)
global at sover.net
www.globalresourceoptions.com

William Miller

At 04:23 AM 12/4/00 -0800, you wrote:
>I have a question for the expertise of this group.  We are in the final
>throws of completing a system (2 racks of 4 ASE 300W modules on trackers 
and
>3000W Whisper (I think), 2 Trace 5548s for 240V on a Trace Power Board,
>about 2000 Ahr battery bank, 20Kw generator, purchased as a package from
>Kiocera ("It will take an electrician only a few hours to get it up and
>running!")).  The power inputs (PV and wind) are connected to the inverter
>side of the 250A battery disconnects, which is our question.  It seems to
>leave the inverter unprotected - you're able to isolate the batteries, but
>to isolate the inverter you need to turn off the PV and wind input
>separately.  This would seem to make sense, but it seems that an 
inattentive
>or inadequately trained homeowner might easily turn off the battery main,
>thinking they were disconnecting power to the inverter, when in fact the 
PV
>and wind would still be powering the units.  We actually did this (left 
only
>the wind connected), and one of the inverters smoked.  So, I would
>appreciate any thoughts and/or remedies.
>Doug McCorkle
>Sunnyside Solar
>
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William Miller
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For info contact list moderator by email:
 michael.welch at homepower.com

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 RE-wrenches at topica.com

The archive of previous messages: 
 http://www.topica.com/lists/RE-wrenches/

To unsubscribe send a message to: 
 RE-wrenches-unsubscribe at topica.com

To check out the other RE-Wrench participants:
 www.mrsharkey.com/wrenches/index.html

Hosted by Home Power magazine: 
 www.homepower.com

For info contact list moderator by email:
 michael.welch at homepower.com

___________________________________________________________
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