[RE-wrenches] Metering

[Glenn Burt]

I would not classify what we are doing in PV as SCADA.

 

It is purely data acquisition at this point, and more commonly referred to
as DAS or a Data Acquisition System.

SCADA by its definition entails a two way path of both receiving data and
being able to send control signals, usually from a big picture program,
monitoring dozens of data points.

Let's not try to make the simple into a more complex thing than it is.

 

-Glenn

 

From: RE-wrenches [mailto:re-wrenches-bounces at lists.re-wrenches.org] On
Behalf Of Ray Walters
Sent: Monday, September 29, 2014 2:31 PM
To: RE-wrenches
Subject: Re: [RE-wrenches] Metering

 

The 2nd problem with the Envoy besides cost is that it isn't always
reliable.    Communication through power lines is not a new or fresh idea,
and has Always been problematic.  Once you install something you are
expected to make it work, and that can be a nightmare on say an 8 module
system that keeps losing communication to one or two modules.  I've had this
exact case, and confirmed multiple times that each micro was working, but
the Envoy had other ideas.
This rush to mega data acquisition makes sense for larger PPA systems, but
can just add tons of call backs and the resulting financial losses and
frustrations for small systems.
I've spent as much time messing with SCADA, as I have with the entire
install itself; now that's ridiculous.  This isn't new either:  I had  SCADA
systems back in the 90s, that had great promise, but ultimately were
extremely hard to implement, and the customer never used after anyway......
The question is: 
What does the customer really need to operate the system vs. "bells and
whistles".....



R.Ray Walters
CTO, Solarray, Inc
Nabcep Certified PV Installer, 
Licensed Master Electrician
Solar Design Engineer
303 505-8760

On 9/29/2014 12:12 PM, August Goers wrote:

Hi Bill,

 

One of the largest benefits of the microinverter system, in my opinion, is
the ability to monitor each module individually. It might seem like ~$500 is
a lot for the Envoy but I think it is well worth it when you think about the
25 year warranty period and included ongoing monitoring. We've had enough
Enphase failures that I would personally really want to be able to keep my
eye on each micro individually.

 

Just a thought, August

 

From: RE-wrenches [mailto:re-wrenches-bounces at lists.re-wrenches.org] On
Behalf Of frenergy
Sent: Sunday, September 28, 2014 2:26 PM
To: RE-wrenches
Subject: [RE-wrenches] Metering

 

CA wrenches,

 

        I'm trying to (for the sake of my monetarily impaired customers)
figure out a less expensive way to meter/monitor small enphase systems.  One
of my local utilities will allow me to just use a remanufactured
utility-grade meter (ala AEE) These meters are inexpensive, robust and
accurate but only display total production.  

 

        The Envoy retails for over $5 bills.  Most of my customers are not
interested in checking their PV system on the internet, well not after a
couple weeks.  I can't seem to find any requirement from PG&E other than in
Section 5.1 of the guidebook: " All systems receiving an EPBB incentive must
install a production meter accurate to +- 5% of actual system output...."
which is pretty vague.  plus the is no CSI incentive  anymore.

 

        Anybody have a suggestion that is different from the remanu utility
meter?....and possibly gives current wattage output, and is "approved" by
PG&E interconnection?

 

TIA

 

Bill








_______________________________________________
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/20140929/174eb5c1/attachment-0002.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.jpg
Type: image/jpeg
Size: 8424 bytes
Desc: not available
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20140929/174eb5c1/attachment-0002.jpg>