ST XR series, anyone tried on yet? [RE-wrenches]

[Matt Lafferty]

William / Wrenches:

William wrote:

> Matt:
>
> With the limited metering available, how do you know the XRs are more
> stable and harvest energy better than the plain ST?  Why would you
> recommend the XR over the Sunny Boy?

Because Gord said I could have a Xantrex shirt!  (I won't wear it until I'm
convinced that it's the right thing to do....long story.  By the way, John
B....???)

Hmmmm.  Was I talking in my sleep again?  I sure don't remember recommending
the XR over a Sunny-Boy.  I do believe that the more viable options we have,
the better off we all are.  There are many factors involved in a purchasing
&/or design decision.  I was merely providing the list with my observations.
The ultimate decision will have to be left up to the individual.

I am personally a High-Volt DC guy for a lot of reasons.  One of these days
I'll write a book and read it to you all for a bedtime story....should give
you all nightmares for life....lol.  Does anybody on this list actually take
anything I say seriously, anyway?

William, I measure these things with my own gear.  I trust nobody!  I'm not
from Missouri, but I have that "show me" mentality.  In fact, I prefer to
show myself.  That is how I learn the best and I am one who makes up my mind
based on my own observations.

We install PV Production Meters (standard kWH meters) on our systems so we
have a running record of production.  I read the PV Meter every time I'm at
a site so I can keep track of day to day, month to month, visit to visit,
production.  This is a very reliable & cost effective means of monitoring
production.

In addition, our PV Techs have gone to these sites, shot the arrays with IV
Curve tracers, and compared the AC output to the DC input.  We have data
loggers installed on some systems, with pyranometers, AC & DC transducer
inputs, etc.  I get the curves, spreadsheets, graphs, etc. from everyplace I
can and go through it.

I put a Fluke 43 (who was it that said Santa Claus hadn't been to his house
yet?) on them if I want to see real-time stuff.  I compare what the 43 shows
me with what the display is telling me.

I stand in front of the machine and watch my gear and observe the equipment.
I clock the PV Meter.  I shut the systems down, disconnect stuff and test
things.  I have customers write down display info and PV Meter reads then
share them with me.  Customers tell me about noises and what their neighbors
do on Saturday afternoons.

I do all this with any equipment.  Especially new products.  Even with the
number of Sunny Boys we have deployed, I still consider them to be new.
Until we have perfect equipment, there is room for improvement by everyone.

Regarding the limited display info on the XR standard display:  I wouldn't
have chosen that approach personally, but it was a business decision they
made.  We have remote meters installed on the XR's so far.  They kinda look
funny with the yellow comm cord rolled up wrapped around the cabinet and the
meter hanging in a Zip-Lock baggy.....we didn't want to permanently install
them until we decided if we'd even keep them.

Regarding any display: It's only a reference.  If you are comfortable with
relying on an Inverter Display for getting your information, then great.
It's one point of reference.

For instance, the speedometer in my truck is about 8% slow because I have
taller tires than original equipment.  I know that.  I account for that in
my driving.  My speedometer is not "right" but at least I know how "wrong"
it is.

I believe in a secondary means of monitoring the production of an inverter
if you really want to know what's happened in the past 365 days.

Pray for Sun!

-Matt Lafferty
pvpro at attbi.com

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

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

List rules & etiquette: http://www.mrsharkey.com/wrenches/etiquete.htm

Check out participant bios: www.mrsharkey.com/wrenches/index.html

Hosted by Home Power magazine

Moderator: michael.welch at homepower.com

==^================================================================
This email was sent to: michael.welch at homepower.com

EASY UNSUBSCRIBE click here: http://topica.com/u/?bz8Qcs.bz9JC9
Or send an email to: RE-wrenches-unsubscribe at topica.com

T O P I C A -- Register now to manage your mail!
http://www.topica.com/partner/tag02/register
==^================================================================