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<HTML><HEAD><TITLE>Re: [RE-wrenches] kwh meters</TITLE>
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<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010>Hi Gary,</SPAN></FONT></DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010></SPAN></FONT> </DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010>You did say you're using the neutral, so I'm assuming
you've got the 5-jaw socket and meter (Form 12S). You also need to make sure the
meter itself is non-detented. </SPAN></FONT><FONT color=#0000ff size=2
face=Arial><SPAN class=421442921-28012010><SPAN class=421442921-28012010>Once
you reconfigure the socket to match the one shown in David's reference you
should be good to go.</SPAN></SPAN></FONT></DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010></SPAN></FONT> </DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010>Not sure which aspect(s) of "utility grade" you need.
I'll assume you mean "revenue grade" accuracy. The generally accepted threshold
for this is +/-2% overall. </SPAN></FONT><FONT color=#0000ff size=2
face=Arial><SPAN class=421442921-28012010>A lot of analog meters (most) are
not certified as "revenue grade" when running in the "backward"
direction. Forget about "certified", they simply are all over the map with
accuracy tolerance in the backward direction. For this reason, many were
disqualified for use in Net Metering applications. Since your use is technically
measuring the Net Generation, your accuracy may be off... Not as far off as some
inverter manufacturers' displays have been in the past, but still
p</SPAN></FONT><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010>ossibly quite a bit off, relatively
speaking. Think in terms of up to +/-5%. </SPAN></FONT><FONT color=#0000ff
size=2 face=Arial><SPAN class=421442921-28012010>Don't know if this matters for
your purposes or not, but I thought I'd throw it out there so you don't have to
go all the way through the learning curve by yourself. <SPAN
class=421442921-28012010>Lonely curve, that one...</SPAN></SPAN></FONT></DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010><SPAN
class=421442921-28012010></SPAN></SPAN></FONT> </DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010><SPAN class=421442921-28012010>If Net Generation
accuracy is critical, you have three fine choices and many that aren't so fine.
</SPAN></SPAN></FONT></DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010><SPAN
class=421442921-28012010></SPAN></SPAN></FONT> </DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010><SPAN class=421442921-28012010>1) The obvious
"easy" one is to get confirmation that your meter is certified Bi-Directional
&/or qualified/certified for Net Metering. Occupants of Meter
Meter Neverland are particularly paranoid person-objects. Gaining a
qualified confirmation of said information may take some sleuthing. Don't bother
trying to get information from GE. </SPAN></SPAN></FONT><FONT color=#0000ff
size=2 face=Arial><SPAN class=421442921-28012010><SPAN
class=421442921-28012010>Start with the vendor who sold it to you.
</SPAN></SPAN></FONT><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010><SPAN class=421442921-28012010>If you have friends who
work in the meter shop of the local electric utility, you might want
to talk with them. <EM>Hint: If you get a blank stare from the meter guy
when you say "Net Meter".... Just smile, excuse yourself, and go get a
donut.</EM></SPAN></SPAN></FONT></DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010><SPAN
class=421442921-28012010></SPAN></SPAN></FONT> </DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010><SPAN class=421442921-28012010>2) If #1 doesn't
pan out, find a meter that does and use it.</SPAN></SPAN></FONT></DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010><SPAN
class=421442921-28012010></SPAN></SPAN></FONT> </DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010><SPAN class=421442921-28012010>3) Use two meters
and do some subtraction. </SPAN></SPAN></FONT></DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010><SPAN
class=421442921-28012010></SPAN></SPAN></FONT> </DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010><SPAN class=421442921-28012010>Pray for
Sun!</SPAN></SPAN></FONT></DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN
class=421442921-28012010></SPAN></FONT><FONT color=#0000ff size=2
face=Arial></FONT> </DIV>
<DIV dir=ltr align=left><SPAN class=421442921-28012010><FONT color=#0000ff
size=2 face=Arial>Matt Lafferty</FONT></SPAN></DIV><BR>
<DIV dir=ltr lang=en-us class=OutlookMessageHeader align=left>
<HR tabIndex=-1>
<FONT size=2 face=Tahoma><B>From:</B> David Brearley<BR></FONT></DIV>
<DIV></DIV><FONT face="Calibri, Verdana, Helvetica, Arial"><SPAN
style="FONT-SIZE: 11pt">Is it a Form 12-S meter? If not, that’s the reason its
not working. Here’s an article you can refer to:<BR><BR><A
href="http://solarprofessional.com/article/?file=SP1_1_pg16_QandA_3&search=">http://solarprofessional.com/article/?file=SP1_1_pg16_QandA_3&search=</A><BR><BR><BR>On
1/28/10 2:57 PM, "<A href="gary@arp-solar.com">gary@arp-solar.com</A>" <<A
href="gary@arp-solar.com">gary@arp-solar.com</A>>
wrote:<BR><BR></SPAN></FONT>
<BLOCKQUOTE><FONT size=2><FONT face="Verdana, Helvetica, Arial"><SPAN
style="FONT-SIZE: 10pt">I am using an analog GE kwh meter on an outback system
with battery backup to a protected loads panel. The AC in to the
inverter is attached to the bottom of one leg of the meter and the AC out of
the inverter is connected to the top of the other leg. This should give me an
accurate record of just the production from the system. The idea is that the
AC IN that will power the protected loads panel at night will come in the
bottom of one leg and turn the meter backwards then exit through the top of
the meter going forward thus cancelling those kwh. out. I have a neutral
hooked to the meter because I am using it to record 120V but I am not getting
accurate readings with this configuration. Any suggestions on metering in this
case? I need a utility grade kwh
meter. <BR> <BR></SPAN></FONT></FONT></BLOCKQUOTE></BODY></HTML>