The difference is that comparing the PE exam to the NABCEP exam is like
comparing brain surgeon board certification for a doctor to a first aid course
exam.
PE is not only a professional exam, it also holds legal status in all 50
states, whereas the NABCEP exam does not.
From: Greg Egan
Those buy America clauses that congress always seems to put in to cover
their butts and wave the flag often don't have any real teeth. Don't know
about that particular one, but most are subject also to various
international trade free trade treaties and agreements, which in many
cases
This is but one of many exceptions noted in the act
“Recovery Act designated country” means a World Trade Organization
Government Procurement Agreement country, a Free Trade Agreement country, or
a least developed country.
https://www.acquisition.gov/far/html/Subpart%2025_6.html
The SQ-Flex can run directly from a high voltage battery/PV system, but with a
battery based system at over 60 volts or so, you have a lot of problems finding
a good charge controller.
So, even with the associated losses you are going to get with an inverter
system, that is probably the only
Way back in my more Liberal days, I was a union member and supporter. But
over the past 20-25 years I have done a 180, and one of the main reasons was
the giant unions attempts at taking over the solar installation business.
Somehow NABCEP got itself associated with the IBEW, at least in
From what I see, NABCEP is heavily hardware oriented, with only a smidgen of
actual problem solving and/or theory. It totally falls apart with battery
based systems, generally way undersizing them.
The actual electrical knowledge required is minimal except for code and
wiring/hardware issues.
That 284 volt number is if the panel is at 25 degrees C. If the panels are in
full sun and with little wind, they can be higher temperature than that even in
cold weather.
An easy way to get a rough check on that is to disconnect the panels and
temporarily haywire an extra panel in series from
Physically impossible unless you have about an acre for panels.
-Original Message-
From: Carl Adams
Sent: Thursday, February 03, 2011 2:18 PM
To: RE-wrenches@lists.re-wrenches.org
Subject: [RE-wrenches] Low light panel
Hello Wrenches,
I'm looking for a panel which will provide
0.7A
module. We could get .4 amps out of the 12 volt panel. No matter
how large the array it can't be done with 60 lumens because the light
disperses at the same rate that the array surface area increases.
Nathan Jones
Power Source Solar
417-827-0738
On Thu Feb 3rd, 2011 4:27 PM CST Warren Lauzon wrote
Do you have any wiring close to the actual sensors or circuit board that
might be interfering with them?
-Original Message-
From: vi...@solarenergydesign.com
Sent: Thursday, February 03, 2011 11:46 AM
To: RE-wrenches
Subject: [RE-wrenches] Data System Puzzle
Sorry for the long post.
).
Joel Davidson
- Original Message -
From: Warren Lauzon
To: RE-wrenches
Sent: Friday, January 28, 2011 3:35 AM
Subject: Re: [RE-wrenches] Roofers installing solar = creative,new
installation methods
We have seen
, Fax 323-258-8885
From: re-wrenches-boun...@lists.re-wrenches.org
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Warren
Lauzon
Sent: Monday, January 31, 2011 10:19 AM
To: RE-wrenches
Subject: Re: [RE-wrenches] Roofers installing solar
We have seen a lot of the roofing companies nibbling around the edges of solar
installs lately. I have only seen a couple of installs personally, and they
were far from what I would call professional or reliable. Not quite as bad as
your example, but in one case they had used Romex to run the
voltage PV module(s)?
Larry
- Original Message -
From: Warren Lauzon
To: RE-wrenches
Sent: Monday, January 24, 2011 11:05 AM
Subject: Re: [RE-wrenches] 10A Charge / load controller
All controllers have failures – most commonly due to user/installer errors.
Of all
Never underestimate how bad an old system can be.
In the past we have seen systems – including those done by “solar companies” –
where part of the battery bank was not even wired in to the system.
From: Kelly Larson
Sent: Thursday, January 13, 2011 12:57 PM
To: RE-wrenches
Subject: Re:
To be honest, I cannot think of any reason ever to replace the electrolyte in a
battery except to replace spillage. If the batteries got to the slush or
freezing point at less than –10F or so, they probably already had problems with
charging.
From: jay peltz
Sent: Wednesday, December 29, 2010
In the 30+ years that we have been in the solar business, we have never seen or
even heard of a single one.
From: Dana
Sent: Wednesday, December 15, 2010 9:10 AM
To: 'RE-wrenches'
Subject: [RE-wrenches] Battery based hydrogen incidents
Ken –
To meet the flow have run 2 and 3 fans to
We have seen a few instances of the batteries themselves blowing, but not from
hydrogen that we could tell. In one case a guy decided to fast charge his
battery bank with a DC welding generator...
From: Allan Sindelar
Sent: Wednesday, December 15, 2010 11:10 AM
To:
Have not seen that in Outback systems before, but have seen it in similar
setups. Never conclusively figured out what caused it, but as the 3-4 instances
all occurred in winter when humidity was very low and static discharge was
common, that could have caused the memory in the internal circuits
Insulation has one major positive effect, it stabilized the temperature of the
battery bank. With enough insulation battery temperature will vary very little
even with big swings in ambient. The one major downside is that in hot weather
or a warm room, they cannot get rid of heat. It is
-wrenches.org] On Behalf Of Warren Lauzon
Sent: Thursday, December 09, 2010 11:28 AM
To: RE-wrenches
Subject: Re: [RE-wrenches] Outback Mate Controller Issues
Have not seen that in Outback systems before, but have seen it in similar
setups. Never conclusively figured out what caused it, but as the 3-4
We use the “inner melt” type of heat shrink and have had few problems with it
compared to the standard heat shrink. As far as Lead plated lugs, I am not sure
I see much advantage to them. Also as far as coatings go, most Vaseline and
other standard grease type are way too temperature sensitive,
a combination might work best: grease on the contact surfaces before,
and 3M spray outside after?
R. Walters
r...@solarray.com
Solar Engineer
On Nov 30, 2010, at 9:47 AM, Warren Lauzon wrote:
We use the “inner melt” type of heat shrink and have had few problems with it
compared
Looks like I had forum permissions set wrong for images, it should work now so
you can see the pictures even if not logged in or registered. Let me know if it
does not work now.
--- Warren Lauzon
From: Allan Sindelar
Sent: Sunday, November 28, 2010 11:58 AM
To: RE-wrenches
Subject: Re: [RE
Any reason the Magnum would not work? Click for more information
From: William Miller
Sent: Sunday, November 28, 2010 9:00 PM
To: RE-wrenches
Subject: Re: [RE-wrenches] sw plus AGS
Jay:
Just bought one two weeks ago from:
http://www.affordable-solar.com/xantrex.generator.start.module.htm
Last I heard they had some of the junction box versions in stock but were out
of the MC4 cable version.
..
Northern Arizona Wind Sun - Electricity From The Sun Since 1979
Solar Discussion Forum:
LED's pretty much last forever, have a poorer light spectrum.
And what Dan said is basically correct in most cases. On a lumen for lumen
basis LED's are not much different than CFL''s.
..
Northern
for that article is no longer
available, but one that is easier to use is available from Ray Walters' web
site. In SolarPro 3.2, February - March 2010, Blake Gleason shows an example
where upsizing the wire size to get 2.6% loss is not economical.
Kent Osterberg
Blue Mountain Solar, Inc.
Warren
Their patented mounting system (!) will not make up for the laws of physics.
And even if it worked as claimed (small wind turbine systems never do,
especially if roof mounted) it is still pretty expensive. They claim 1400
watts, but typically such an install would get around 1/4 of that for
To be honest, I don't think the question makes any sense. There are several
right answers, but no good ones. I hope that is not the extent of the battery
questions on that exam.
..
Northern Arizona
And it does not help that MC connectors are only one of several types, such as
Tyco and others.
..
Northern Arizona Wind Sun - Electricity From The Sun Since 1979
Solar Discussion Forum:
.
Cheers,
Larry Crutcher
Uni-Solar Certified Installer
Starlight Solar Power Systems
(928) 342-9103
Mailing Address:
11881 S. Fortuna Road, #210
Yuma, AZ 85367
Retail Store Shipping Address:
2998 Shari Ave.
Yuma, Az 85365
- Original Message -
From: Warren Lauzon
The US-64's were on their site for 3+ years after they discontinued them. They
don't keep it updated very well.
I believe the main reasons the peel and stick were discontinued was high
failure rates, high temperature losses (due to very little heat/air
dissapation), and the difficulties in
The kicker is the large startup, so you may need to use batteries with low
internal resistance, such as the Concorde AGM's. You will also have to make
sure your cables are good for the max current to avoid any voltage drop which
would cause a low voltage shutdown.
Aside from that, just go with
At one time Dankoff (the pre-Conergy Dankoff Solar) handled the the Lorentz
submersibles. They dropped them after about a year because of failures.
Now, that was several years ago and Lorentz may have gotten their problems
fixed, but we have felt more comfortable with the Grundfos.
Uhm. not quite.
The insistence of MC to use their tool has nothing to do with code, NEC, UL, or
anything else.
It has to do with (1) sales, (2) liability, and (3) quality control.
For (2) it means that if a connector fails, burns down the house, and kills 93
chickens that they are not liable
We usually figure that (for example) in a 2-string bank, that one conductor
could carry 2/3 of the current if the batteries are unbalanced for some reason.
In other words, rather than cutting the amperage rating in half, we cut it by
about 1/3. For 3 banks would cut it by 1/2, etc.
Probably
Just for info, here is a good example of how and how not to wire up
batteries for balanced amperage draw
http://www.smartgauge.co.uk/batt_con.html
..
Northern Arizona Wind Sun - Electricity From
We have this one http://www.windsun.com/Hardware/Voltage_Calc.htm on our info
site. Not very elegant, as it was done in a couple of hours (we really need to
get that cleaned up...) but it works.
It is the similar to many others but we had it modified by a java script
programmer to allow any
From: re-wrenches-boun...@lists.re-wrenches.org
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Warren Lauzon
Sent: Saturday, February 20, 2010 11:24 AM
To: RE-wrenches
Subject: Re: [RE-wrenches] Rennsteig Crimper Tool
Uhm. not quite.
The insistence of MC to use
In your case, yes the battery cables should also be 4/0. They are carrying the
same load as the inverter cables. Max amp rating on 2/0 is around 190 amps, and
that inverter can surge to well over 250, even though at 4kw it would pull
around 180.
And a nitpick - those are not cells, they are
The Vmp of those is 33.7 volts, so what you might want to do is just come up
with a set of panels that would equal 10 of the SX120's within 5% or less. As I
recall, the SX120's had a rather poor temperature coefficient compared to
todays panels, so that might be hard to match up.
Have any of us here ever heard of a world renowned battery guru? You have to
wonder why, if they are world renowned, they have to do home shows.
Refractometers have been used quite commonly in labs, but those are in the $500
an up range. Some pretty decent ones for home use are in the $75-$150
I am inclined to agree with that. We are in the process of revising our
recommendations on equalizing. It perhaps made sense to do so every month or
so 20 years ago, but I am wondering if that really is a good idea with the
current state of battery chargers and controllers.
The answer to systems not being used is nearly always leave them on float.
However, 2 amps seems a bit high for AGM batteries unless you have some kind
of phantom load.
Equalization for AGM's is different and for a different purpose than with
flooded. The current should be quite a bit less
While it is good to see the Dankoff name back, I would also note that
Innovative is a direct competitor to most people on this list.
..
Northern Arizona Wind Sun - Electricity From The Sun Since 1979
I tried running one of the Outback manuals through the Google translator,
and it came out pretty awful in Spanish - it has problems with technical
terms it seems. I don't know enough German to say either way.
Try Hitney Solar, they usually have a few.
..
Northern Arizona Wind Sun - Electricity From The Sun Since 1979
Solar Discussion Forum: http://www.wind-sun.com/ForumVB/
Re: [RE-wrenches] Capacity loss due to rapid dischargeThat is not quite true.
Some of the loss is in heat due to internal resistance, and that cannot be
recovered. High discharge rates also significantly affect overall battery life,
which is not part of the equation but must be considered.
Better than no ground at all, but not reliable. Some codes allow it, but we
would never use it for a main ground.
..
Northern Arizona Wind Sun - Electricity From The Sun Since 1979
Solar Discussion
That is a problem we have not seen before with those inverters, though not
unheard of with electronics in general. From my experience it is usually due to
an electrolytic capacitor being out of spec (or wrong one)., but can also be
from some solid state component, or even the main processor or
The only way to really prevent that is to disconnect everything but the solar
array. Unfortunately, more than once we have seen customers disconnect the
array but leave other phantom loads on.
When most inverters shut down on LV they are still drawing a few watts. And
even with solar
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