[RE-wrenches] eternabond or epdm?

[Mark Dickson]

Wrenches,

It has been a while since I have seen this subject and I was wondering if
there has been more experience in the field with using either EPDM or
products such as http://www.eternabond.com/DoubleStick-p/cr-ds.htm for
sealing L-feet or stand-offs directly to metal roofing. . .

Seems to make sense to directly seal off the one or two holes for that lags
rather than placing a boot over it and drilling 20 screws around the Otey.
The only weakness I could see would be the seal directly over the lags, but
I think this could be cured with a dollop of silicone or other EPDM safe
caulk in and on top of the hole.

My main worry is the compression of the material over time, which may
compromise the bond/seal.

 

Has anyone successfully used the Eternabond-looks like it could be a good
solution.

 

 

Best regards,

 

Mark Dickson,

NABCEP Certified Solar PV Installer T

Oasis Montana Inc.

 

  _  

From: re-wrenches-boun...@lists.re-wrenches.org
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of William
Miller
Sent: Sunday, November 14, 2010 10:36 PM
To: RE-wrenches
Subject: Re: [RE-wrenches] Head Spinning..(Con) fused.

 

Eric:

Thanks for the research.  I confess that I commented on an inverter system I
knew little about.  My thanks to Darryl for keeping me honest, and for the
kind words.  I had assumed that all modern inverters are certified to
prevent back feed, but this needs to be checked for each new inverter.

I'm not sure the language below is the same as an independent verification
that back feed will not occur.  You may need to ask your AHJ what they will
accept.

The limit on allowable back current is the fuse sizing specified by the
module manufacturer.  This relates to how much fault current the internal
module wiring can handle before it fails (and possibly catches fire).

Humbly,

William Miller





At 07:42 PM 11/14/2010, you wrote:



Thanks William and Daryl,

Here is Auroras backfeed stipulation from the installation manual:

"Installation and Operator's Manual Page 98 of 108

(PVI-3.0/3.6/4.2-OUTD-x-US Rev: 2.1)

8.5 Input Source Backfeed Current

PVI-4.2(3.6, 3.0)-OUTD-x-US Grid Tied Inverters are provided with two
separate and
consecutive power stages:

. Booster Stage (DC-DC converter) connected to DC Input Terminals.
. Inverter Stage (DC-AC converter) connected to AC Output Grid Terminals.

The Booster Stage is provided with forward diodes that allows the current
(power)
flow only from DC Input terminals towards Inverter (Output) Stage.
In case of any fault on Inverter Stage, these diodes avoid any back-feed
current
phenomena towards input terminals.

In case of fault of the forward diode, the corresponding booster MOSfet goes
immediately and permanently in short circuit state and it avoids any current
propagation form output to input terminals.

Abnormal Fault tests conducted during UL1741 qualification show also that
these type
of faults produce the opening of internal grid disconnect relays and cause
the external
AC CB protection devices to trip, preventing any power flow from the grid.

In conclusion for PVI-4.2(3.6, 3.0)-OUTD-x-US-y models it is not possible to
have
any single fault responsible of Input source back-feed current flow. For
these models
the Back-feed current into DC Source is negligible."

According to this, the inverter will not backfeed even under most fault
conditions. My biggest concern is the four independent strings shorting
together somehow. I guess technically 4 strings of 8A for a total of 32A
doesn't exceed the ampacity of 10AWG XHHW-2until you derate it for roof
temps. 

So whats the consensus?

-- 
Eric Thomas
Solar Epiphany LLC
(206) 919-3014
www.solarepiphany.com

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Checked by AVG - www.avg.com   
Version: 8.5.449 / Virus Database: 271.1.1/3257 - Release Date: 11/14/10
19:34:00

Please note new e-mail address and domain:

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Miller Solar
Voice :805-438-5600
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Re: [RE-wrenches] eternabond or epdm?

[Richard L Ratico]

Hi Mark,

Having learned of Eternabond on this list, we've since used the doublestick 
version on two, raised rib type metal roofs. Of course, it's way too early to 
tell how it will perform over time, but we were quite impressed during
installation.  
It's ferociously sticky. You'll want to place your L-feet very carefully.

We went with the dollop of silicone (Lexel) followup, though Eternabond does 
make a single stick product that might be appropriate to place over top of 
the lags. The stuff does squeeze out well while tightening the lags. My sense
was the teeth on the L-feet bottoms were very close to, if not touching the 
metal roofing surface, meaning no more compression over time.

I like it better than the traditional use of schmutz alone. Twenty screws
around an Oatey flashing seems nuts unless you have an irregular surface
to conform to, or for your conduit roof penetration.

Need a new metal roof? Go with true standing seam pans and use Unisolar PVL
modules.

Dick Ratico
Solarwind Electric

--- You wrote:
Wrenches,

It has been a while since I have seen this subject and I was wondering if
there has been more experience in the field with using either EPDM or
products such as http://www.eternabond.com/DoubleStick-p/cr-ds.htm for
sealing L-feet or stand-offs directly to metal roofing. . .

Seems to make sense to directly seal off the one or two holes for that lags
rather than placing a boot over it and drilling 20 screws around the Otey.
The only weakness I could see would be the seal directly over the lags, but
I think this could be cured with a dollop of silicone or other EPDM safe
caulk in and on top of the hole.

My main worry is the compression of the material over time, which may
compromise the bond/seal.

 

Has anyone successfully used the Eternabond-looks like it could be a good
solution.

 

 

Best regards,

 

Mark Dickson,

NABCEP Certified Solar PV Installer T

Oasis Montana Inc.
--- end of quote ---
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[RE-wrenches] String Level Monitoring in Combiners

[Matt Lafferty]

Hola Wrenches,
 
The topic of string level monitoring keeps coming up in my circles.
Personally, i think it's dumb in most non-R&D applications. Dumb is actually
a little weak for how i really feel about it, but that's the word i'll use
today. For the purpose of keeping it straight, i'm talking about real
strings. Not to be confused with re-combiner inputs. i advocate mapping and
monitoring all re-combiner inputs in central-inverter applications.
 
Part of my perspective comes from the fact that monitoring string data
inherently assumes that you are monitoring the system-level outputs anyway,
and know how to evaluate that data. Any "benefit" of string-level monitoring
must be over and above the benefits of monitoring without it. System outputs
are what matter, right? So why focus on strings? What are you waiting for?
Expecting something wierd to happen? Are you looking for binary information
(On/Off) or comparative data from one string to the next? How do you account
for instrumentation accuracy tolerances compared to module tolerances? Are
you looking for trends, such as seasonal shading from one string to another?
Or trends such as decreasing current in strings over time? Are you really
gonna make a point of going back and normalizing point-in-time current
measurements to point-in-time environmental conditions overlayed with
point-in-time soiling data and comparing them? Really? And then what? 
 
"Gee, there's a 7% difference in normalized String 5 from the same 15-minute
interval last year, George. Ya think we should go out and see if there's
something wrong?" 
 
The real answer is, no. You and yours are not gonna go out there for that
unless you are gluttons for punishment and don't have anything better to do.
Or simply don't know better. Here' why: Unless there is some other sign of
system output being off, it's not worth chasing the wild goose. 
 
If the system output is down from what it should be, you gotta go out and
find the problem anyway. When you get there, you will follow these steps:
 
A)  Visual observation 
B)  Data gathering from meters and displays
C)  Compare field observations and data to monitored data
D)  Determine whether or not there is actually a performance problem and
begin troubleshooting if necessary
E)  Troubleshooting Step 1: Clamp individual string inputs at the combiner
and compare to others.
 
You gotta go thru these steps anyway. Whether or not you have string
monitoring. So string monitoring doesn't save you a danged thing here.
 
Now, i know you youngsters trust that monitoring thing, and are ready to
jump right in the middle of String 5 and skip all that troubleshooting
nonsense... Hey, your i-phoidberry said it was String 5, right? You go right
ahead. Let me know how that works out for ya... Over time. No, silly... Not
"overtime"... Two words. Over. Time. Actually, when it comes right down to
it, i don't really care how it works out for you as much as i care how it
works out for the customer and your boss. You're getting paid whether it
works out or not. At least for awhile. The customer and your boss are most
likely NOT getting paid if it doesn't work out... Keep that in mind.
 
"Are you sure that's String 5? I thought String 5 was this one... Dang! We
didn't actually number the strings on the modules, did we?. I guess we gotta
open up that combiner anyway"
 
And what are you gonna do to String 5 anyway? Pull it all apart and... What?
Without checking it side-by-side with the others in the combiner first?
Really? What's that gonna get you? A pile of modules about one string high
and no answers. That's what.
 
Ever had to have a test instrument calibrated? Ever heard of a thing called
"drift"? Measurement accuracy tolerance? Improper use of a calculator? How
about just being too uptight and data-centric to see the big picture? Ever
heard of any of these? I've already seen thousands of dollars wasted in
truck-rolls to "fix a string", only to find out that a channel on string
level monitoring board failed and there wasn't really a performance problem
after all. Unless you count the monitoring board's lack of performance as a
problem.
 
i can certainly see where having string level monitoring could be handy as a
reference. Assuming that it's working correctly and all. But only in a very
limited number of circumstances. For example, just before going out to do
maintenance on a system, you take a look across the graphs and see if there
are any problem-children out there so you can take an extra good look at
some part of the array when you are out there. Current, in this application,
is real-time and not cumulative. It's not like you're doing amp-hour
calculations... Which might have value in a
pocket-protector-basement-of-the-science-building sort of way... IF you were
doing high-resolution sampling and data parsing and actually still have a
pocket protector and reside in the basement of the science building. 
 
i advocate doing a clamp-compare-test, on each string in

Re: [RE-wrenches] Head Spinning..(Con) fused.

[Bill Brooks]

Eric,

 

Your concern over shorting the current carrying conductors to a single
conductor would require multiple faults-not that this is impossible-but we
generally are not required to design for it. Squirrels would probably be the
most likely way to cause such an event.

 

Since all four strings are going into separate input stages, if any of the
conductors were to come into electrical contact with each other or the
conduit, it would likely trip the very sensitive ground-fault detectors.
Series fuses are unlikely to have any plausible scenario that would cause
them to operate. 

 

Bill.

 

From: re-wrenches-boun...@lists.re-wrenches.org
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Eric Thomas
Sent: Sunday, November 14, 2010 7:43 PM
To: re-wrenches@lists.re-wrenches.org
Subject: Re: [RE-wrenches] Head Spinning..(Con) fused.

 

Thanks William and Daryl,

Here is Auroras backfeed stipulation from the installation manual:

"Installation and Operator's Manual Page 98 of 108

(PVI-3.0/3.6/4.2-OUTD-x-US Rev: 2.1)

8.5 Input Source Backfeed Current

PVI-4.2(3.6, 3.0)-OUTD-x-US Grid Tied Inverters are provided with two
separate and
consecutive power stages:

. Booster Stage (DC-DC converter) connected to DC Input Terminals.
. Inverter Stage (DC-AC converter) connected to AC Output Grid Terminals.

The Booster Stage is provided with forward diodes that allows the current
(power)
flow only from DC Input terminals towards Inverter (Output) Stage.
In case of any fault on Inverter Stage, these diodes avoid any back-feed
current
phenomena towards input terminals.

In case of fault of the forward diode, the corresponding booster MOSfet goes
immediately and permanently in short circuit state and it avoids any current
propagation form output to input terminals.

Abnormal Fault tests conducted during UL1741 qualification show also that
these type
of faults produce the opening of internal grid disconnect relays and cause
the external
AC CB protection devices to trip, preventing any power flow from the grid.

In conclusion for PVI-4.2(3.6, 3.0)-OUTD-x-US-y models it is not possible to
have
any single fault responsible of Input source back-feed current flow. For
these models
the Back-feed current into DC Source is negligible."

According to this, the inverter will not backfeed even under most fault
conditions. My biggest concern is the four independent strings shorting
together somehow. I guess technically 4 strings of 8A for a total of 32A
doesn't exceed the ampacity of 10AWG XHHW-2until you derate it for roof
temps. 

So whats the consensus?

-- 
Eric Thomas
Solar Epiphany LLC
(206) 919-3014
www.solarepiphany.com

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[RE-wrenches] 120 volt grid tie inverter

[Bob Ellison]

I have a customer who wants to grid tie a 120 volt dc system
Does anyone know of an inverter that can do this?

Thanks
Bob ellison


> 

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Re: [RE-wrenches] 120 volt grid tie inverter

[Mick Abraham]

Hi, I don't know if you mean "120 volt nominal" or 120 volt peak power
voltage, but assuming the latter:

* Consider the PV Powered 2000 watt unit. Operating range begins at 114
volts DC which is still borderline, OR:

* Enphase if the volts & amps happen to work out with serendipity, OR:

* Aurora also has a string inverter with a low minimum DC input voltage, but
it's transformerless so it's double fuses, double insulated wire, etc.

Let us give thanks,

Mick Abraham, Proprietor
www.abrahamsolar.com

Voice: 970-731-4675


On Mon, Nov 15, 2010 at 9:13 AM, Bob Ellison  wrote:

> I have a customer who wants to grid tie a 120 volt dc system
> Does anyone know of an inverter that can do this?
>
> Thanks
> Bob ellison
>
>
> >
>
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Re: [RE-wrenches] 120 volt grid tie inverter

[Glenn Burt]

I think there is still an SMA 700W inverter available that uses 120VAC.
-Glenn

-Original Message-
From: re-wrenches-boun...@lists.re-wrenches.org
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Bob Ellison
Sent: Monday, November 15, 2010 11:14 AM
To: RE-wrenches
Subject: [RE-wrenches] 120 volt grid tie inverter

I have a customer who wants to grid tie a 120 volt dc system
Does anyone know of an inverter that can do this?

Thanks
Bob ellison


> 

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Re: [RE-wrenches] 120 volt grid tie inverter

[Peter Parrish]

Bob,

Do you mean they have a nominal 120 Vdc input? Or do you mean that they want
a 120 Vac (RMS) output? If the former, what output voltage do you want? If
the latter, what is their nominal dc input voltage (better yet the range of
DC input voltages over a range of typical temperatures and irradiance
values)?

- Peter

 
Peter T. Parrish, Ph.D., President
California Solar Engineering, Inc.
820 Cynthia Ave., Los Angeles, CA 90065
CA Lic. 854779, NABCEP Cert. 031806-26
peter.parr...@calsolareng.com  
Ph 323-258-8883, Mobile 323-839-6108, Fax 323-258-8885

 
-Original Message-
From: re-wrenches-boun...@lists.re-wrenches.org
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Glenn Burt
Sent: Monday, November 15, 2010 5:29 PM
To: 'RE-wrenches'
Subject: Re: [RE-wrenches] 120 volt grid tie inverter

I think there is still an SMA 700W inverter available that uses 120VAC.
-Glenn

-Original Message-
From: re-wrenches-boun...@lists.re-wrenches.org
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Bob Ellison
Sent: Monday, November 15, 2010 11:14 AM
To: RE-wrenches
Subject: [RE-wrenches] 120 volt grid tie inverter

I have a customer who wants to grid tie a 120 volt dc system
Does anyone know of an inverter that can do this?

Thanks
Bob ellison


> 

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Re: [RE-wrenches] String Level Monitoring in Combiners

[Nick Soleil]

Hi Matt:
If it were inexpensive and reliable, then it would be a good thing.  Until 
it is, the clamp-on meter works for me.  

This ties into the conversations about burned up modules, which I 
frequently 
see on projects that I service.  I find that most of the module failures occur 
due to overheating at the j-boxes.  The failure of these contacts will often 
begin as an intermittent contact, and result to a melt down or burn out.  These 
failures are causing such heat, that the glass frequently shatters.  I have 
felt 
the glass getting as hot as a stove top, you could cook on it!  Often times, 
these faillures will take out the whole string.  

These types of failures, or partial shading issues, can more quickly be 
spotted and addressed with string level monitoring.  I have installed many 
Enphase systems, and I love being able to check all my projects outputs from my 
desk.  I recently saw that one of my customer's modules wasn't producing power, 
I called him up, and he walked out to his ground mounted array.  I asked if any 
weeds were shading the module, and he said, "Yes."  He pulled the grass out, 
and 
the output of the modules returned to full power on the monitor.  Those types 
of 
issues will go one for ever in systems with less detailed monitoring.

 Nick Soleil
Project Manager
Advanced Alternative Energy Solutions, LLC
PO Box 657
Petaluma, CA 94953
Cell:   707-321-2937
Office: 707-789-9537
Fax:707-769-9037





From: Matt Lafferty 
To: RE-wrenches 
Sent: Mon, November 15, 2010 11:35:36 AM
Subject: [RE-wrenches] String Level Monitoring in Combiners


Hola  Wrenches,
 
The topic of string  level monitoring keeps coming up in my circles. 
Personally, 
i think it's dumb in  most non-R&D applications. Dumb is actually a little weak 
for how i  really feel about it, but that's the word i'll use today. For the 
purpose of keeping it  straight, i'm talking about real strings. Not to be 
confused with re-combiner  inputs. i advocate mapping and monitoring all 
re-combiner inputs in  central-inverter applications.
 
Part of my  perspective comes from the fact that monitoring string data 
inherently assumes  that you are monitoring the system-level outputs anyway, 
and 
know how to  evaluate that data. Any "benefit" of string-level monitoring must 
be over  and above the benefits of monitoring without it. System outputs are 
what matter, right?  So why focus on strings? What are you waiting for? 
Expecting something wierd to  happen? Are  you looking for binary information 
(On/Off) or comparative data from one string  to the next? How do you account 
for instrumentation accuracy tolerances compared  to module tolerances? Are you 
looking for trends, such as seasonal shading from  one string to another? Or 
trends such as decreasing current in strings over  time? Are you really gonna 
make a point of going back and normalizing  point-in-time current measurements 
to point-in-time environmental conditions  overlayed with point-in-time soiling 
data and comparing them? Really? And then  what? 

 
"Gee, there's a  7% difference in normalized String 5 from the same 15-minute  
interval last year, George. Ya think we should go out and see if there's  
something wrong?" 

 
The real answer is,  no. You and yours are not gonna go out there for that 
unless you are gluttons  for punishment and don't have anything better to do. 
Or 
simply don't know  better. Here' why: Unless there is some other sign of system 
output being off,  it's not worth chasing the wild goose. 

 
If the system output  is down from what it should be, you gotta go out and find 
the problem anyway.  When you get there, you will follow these steps:
 
A)  Visual  observation 
B)  Data  gathering from meters and displays
C)  Compare  field observations and data to monitored data
D)  Determine  whether or not there is actually a performance problem and begin 
troubleshooting  if necessary
E)   Troubleshooting Step 1: Clamp individual string inputs at the combiner and 
 
compare to others.
 
You gotta go thru  these steps anyway. Whether or not you have string 
monitoring. So string monitoring doesn't save you a  danged thing here.
 
Now, i know you  youngsters trust that monitoring thing, and are ready to jump 
right in the  middle of String 5 and skip all that troubleshooting nonsense... 
Hey, your  i-phoidberry said it was String 5, right? You go right ahead. Let me 
know how  that works out for ya... Over time. No, silly... Not "overtime"... 
Two 
words.  Over. Time. Actually, when it comes right down to it, i don't  really 
care how it works out for you as much as i care how it works out for the  
customer and your boss. You're getting paid whether it works out or not. At  
least for awhile. The customer and your boss are most likely NOT getting paid 
if  
it doesn't work out... Keep that in mind.
 
"Are you sure  that's String 5? I thought String 5 was this one... Dang! We 
didn't actua

Re: [RE-wrenches] 120 volt grid tie inverter

[Mick Abraham]

Agreed, Glenn~ and that SMA unit has a nice low input voltage requirement.

Bob, might your client be wanting a "grid intertie capable" inverter which
can run on a 120 volt battery bank--the medium voltage battery system which
Chad Lampkin had championed? If so, it's game over for several reasons,
including the NEC.

Jolliness,

Mick Abraham, Proprietor
www.abrahamsolar.com

Voice: 970-731-4675


On Mon, Nov 15, 2010 at 6:29 PM, Glenn Burt  wrote:

> I think there is still an SMA 700W inverter available that uses 120VAC.
> -Glenn
>
> -Original Message-
> From: re-wrenches-boun...@lists.re-wrenches.org
> [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Bob
> Ellison
> Sent: Monday, November 15, 2010 11:14 AM
> To: RE-wrenches
> Subject: [RE-wrenches] 120 volt grid tie inverter
>
> I have a customer who wants to grid tie a 120 volt dc system
> Does anyone know of an inverter that can do this?
>
> Thanks
> Bob ellison
>
>
> >
>
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[RE-wrenches] Inspectors on ladders and roofs

[Keith Cronin]

Wrenches

Today, when I ran into one of our electrical inspectors, we had a discussion 
about having the ability to have thorough inspections for solar.
In our jurisdictional, they are not allowed/required to go on to the roof.

So, how do they ever get to see all of the grounding and mounting methods used 
on a roof and verify whether or not they are adequate?

Sure, they ask to open the electrical infrastructure on the ground, but what 
about the stuff on top? Combiner box check? 

Wiring routed in a way that meets the standard?

What's it like by you?

Thanks

Keith___
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Re: [RE-wrenches] 120 volt grid tie inverter

[David Katz]

Has anyone tried string sizing 60 cell modules to an SMA 700.  It is not 
possible.


David Katz

Founder & CTO

AEE Solar

T(707) 825-1200

C(831) 325-9582

F(707) 825-1202

dk...@aeesolar.com 

www.aeesolar.com 


On 11/15/2010 5:29 PM, Glenn Burt wrote:

I think there is still an SMA 700W inverter available that uses 120VAC.
-Glenn

-Original Message-
From: re-wrenches-boun...@lists.re-wrenches.org
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Bob Ellison
Sent: Monday, November 15, 2010 11:14 AM
To: RE-wrenches
Subject: [RE-wrenches] 120 volt grid tie inverter

I have a customer who wants to grid tie a 120 volt dc system
Does anyone know of an inverter that can do this?

Thanks
Bob ellison


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Re: [RE-wrenches] Inspectors on ladders and roofs

[Mike Nelson]

Keith,
Here in rural Mendocino & Sonoma county, our inspectors love to climb on the
roof, and look at everything. I've opened combiner boxes, explained WEEBS,
talked about sub-structure in the roof, etc. I always get to the job early
on inspection day, and set up a ladder in an easy to climb location. I
welcome the opportunity to interface with the inspectors, and hear their
side, which usually includes alot of questions, and some interesting
stories.
Michael D. Nelson
MD Electric & Solar
Gualala Ca.

On Mon, Nov 15, 2010 at 6:37 PM, Keith Cronin wrote:

>   Wrenches
>
> Today, when I ran into one of our electrical inspectors, we had a
> discussion about having the ability to have thorough inspections for
> solar.
> In our jurisdictional, they are not allowed/required to go on to the roof.
>
> So, how do they ever get to see all of the grounding and mounting methods
> used on a roof and verify whether or not they are adequate?
>
> Sure, they ask to open the electrical infrastructure on the ground, but
> what about the stuff on top? Combiner box check?
>
> Wiring routed in a way that meets the standard?
>
> What's it like by you?
>
> Thanks
>
> Keith
>
> ___
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>
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[RE-wrenches] Outback Gen starting case study

[William Miller]

Colleagues:

I had posted earlier that I was having problems reliably starting a 
particular generator using an Outback Mate.  My resolve was to determine 
conclusively if the Outback mate was at fault or if I could trust it in the 
future.  I installed a data monitoring system to check battery voltage, gen 
start signal and gen AC waveform and briefed the care taker and staff to 
scrutinize the system carefully during the test period.  Here are the results:


There were 4 generator start failures over a period of about 4 weeks. 
Failure numbers 1 and 3 were verified to have been caused by the 
generator.  Failures 2 and 4 were due to failure of the customer to reset 
the Mate after failures 1 and 3.  This was a training error that was partly 
mine.  No failures can be blamed on the Outback equipment.


Moral of the story:  Generator start systems are complicated.  You need to 
know your generator and your customer needs to know his or her Mate.  But, 
the Mate AGS works.


More information:

The Kohler RES 15 displays numerals under normal circumstances and alpha 
characters under abnormal circumstances.  I posted a note in the generator 
shed informing anyone that if alpha characters are seen, to note the 
characters, time, date and then to call me.


The Mate is difficult enough for the technician to understand.  My customer 
has an elderly caretaker for whom English is a second language.  After I 
discovered the training error, I created a few flip charts with lots of 
graphics and copies translated into Spanish, followed up by on-site 
training.  This should prevent repeats of the failure to clear AGS 
Errors.  This highlights the industry wide problem of systems having too 
complicated a front end.


Data monitoring proved the point that generator failure was the original 
culprit.  If anyone is interested in more information about a roll-your-own 
low-budget data monitoring system, I created a page on the 
subject:  http://millersolar.com/case_studies/Data/data.html


I firmly believe that third party generator start hardware adds an 
unnecessary level of complication and removes the added feature of tieing 
generator stop to the float stage.  I will continue to use and recommended 
the Outback integrated AGS system.


William Miller




Please note new e-mail address and domain:

William Miller
Miller Solar
Voice :805-438-5600
email: will...@millersolar.com
http://millersolar.com
License No. C-10-773985
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