to equalize the battery until there is enough room for the
replacement acid. Fortunately, it doesn't have to be done in one step.
Since there was acid between the inner and outer case originally, I'd
inspect carefully to make sure it is not filled with acid again.
Kent Osterberg
Blue Mountain
Larry,
It sounds like the customer can power all loads with the generator and
the non-critical load may even be the motivation for starting the
generator? How about a relay that opens the SunnyBoy output or the Sunny
Island input when the generator runs?
Kent Osterberg
Blue Mountain Solar
, a 100-amp 24-volt charge puts about 25 amps (if you are
careful with the wiring and the batteries aren't sulfated) into each
string of batteries. A 50-amp 48-volt charger would accomplish the same
thing.
Kent Osterberg
Blue Mountain Solar, Inc.
www.bluemountainsolar.com
t: 541-568-4882
On 1/17
the charge rate (C/X) that the batteries see is the same either way.
Considering that lots of parallel strings of batteries is trouble
waiting to happen and that a 48-volt system is more efficient, except
for the smallest systems 48-volts is usually the way to go.
Kent Osterberg
Blue Mountain Solar, Inc
the charge rate (C/X) that the batteries see is the same either way.
Considering that lots of parallel strings of batteries is trouble
waiting to happen and that a 48-volt system is more efficient, except
for the smallest systems 48-volts is usually the way to go.
Kent Osterberg
Blue Mountain Solar, Inc
cells removed.
Kent Osterberg
Blue Mountain Solar, Inc.
www.bluemountainsolar.com
t: 541-568-4882
On 1/17/2012 11:19 AM, Mark Frye wrote:
Interesting.
I can choose an OB VFX3524 w/ 85 ADC or an OB VFX3648 w/ 45 ADC of charging
capacity.
And assuming that I need C/10 during bulk charging
it is
intended to to cover all batteries and it is intentionally conservative.
Kent Osterberg
Blue Mountain Solar, Inc.
www.bluemountainsolar.com
t: 541-568-4882
On 1/6/2012 5:53 PM, John DeBoever wrote:
Wrenches,
Thank you for your patience (as I was busy all day). I appreciate the
valid
are air cooled.
Kent Osterberg
Blue Mountain Solar, Inc.
www.bluemountainsolar.com
t: 541-568-4882
On 1/9/2012 7:59 PM, Allan Sindelar wrote:
Wrenches:
We have cautiously agreed to take on a substantial upgrade and
rehabilitation of a poorly designed 48V off-grid system. Our upgrade
Wrenches,
While looking for information regarding standards about battery room
ventilation I ran into this link, which has some good information and is
certainly worth everyone's attention.
http://www.belvoir.army.mil/safety/inc/battery-explosion.asp
Kent Osterberg
Blue Mountain Solar, Inc
Ray,
The balancing transformer isn't allowed with the GVFX inverters. In a
dual FX inverter system, using the balancing transformer or not using it
is nearly a wash. I think you save 15 watts when the inverter is asleep
but the transformer losses are 10 or 12 watts.
Kent Osterberg
Blue
John,
Could you clarify units? "0.418 Liters/AH" is that per charge cycle?
per hour? per minute? per cell?
Kent Osterberg
Blue Mountain Solar, Inc.
www.bluemountainsolar.com
On 1/5/2012 4:18 PM, John DeBo
, but what happens when the power vent fails? It will fail. I've
seen the bearings wear out on one and another that failed when insects
got into the blades and gummed it up to the point that the motor stalled.
Kent Osterberg
Blue Mountain Solar, Inc.
www.bluemountainsolar.com
t: 541-568-4882
Here, by code, vents must extend 12 above the roof line. It's a bad
idea to cover them with PV modules.
Kent Osterberg
Blue Mountain Solar, Inc.
www.bluemountainsolar.com
t: 541-568-4882
On 12/15/2011 11:31 AM, Allen Frishman wrote:
Wrenchers,
My local JHA has recently decided that vents
the H2 levels below the explosive
threshold.
Kent Osterberg
Blue Mountain Solar, Inc.
www.bluemountainsolar.com
t: 541-568-4882
On 12/14/2011 4:46 PM, d...@foxfire-energy.com wrote:
I've mentioned it in the past, and got the impression it went over
like a fart in church, but it seems to me
coordination
issues. The Tristar 60 manual says to keep diversion loads below 45 amps
(or somewhere close to that). I think its a reliability issue so with a
secondary shut down method, you might be okay pushing it a bit. I'm not
sure how you get two of them to work together.
Kent Osterberg
true for c-Si or poly-Si.
Kent Osterberg
Blue Mountain Solar, Inc.
www.bluemountainsolar.com
t: 541-568-4882
On 11/29/2011 11:48 AM, Kirk Herander wrote:
I am in debate with a PE over calculation of low voltage of a series
string on a hot day. He insists that an arbitrary high cell temp
300.9 but rather from
110.3 (B) that requires equipment to be installed in accordance with
its listing.
Kent Osterberg
Blue Mountain Solar
Glenn Burt wrote:
Kent,
Can you
direct me to a code citation that says that splices made inside a NEMA
4 rated enclosure must be suitable
Jason,
The roof is a wet location so connectors rated for wet locations are
required. The NEMA 4 rating of the junction box doesn't change matters.
Kent Osteberg
Blue Mountain Solar
Jason Szumlanski wrote:
Anyone see a problem using Ideal In-Sure Push-In
Wire Connectors in
that an
appropriate safety factor needs to be applied.
Kent Osterberg
Blue Mountain Solar
Jamie Johnson wrote:
Dave, thanks for the clarification on the difference between
NRTL and IEC tests.
Wouldn't it make sense for the manufacturers to put the negative
and positive test and certified
grounding electrode, the changes in 2011 should remove it.
Kent Osterberg
Blue Mountain Solar, Inc.
Richard L Ratico wrote:
As Dan points out, 250.52(A)(3) specifies several installation requirements in
order for a concrete encased electode to qualify as a permitted Grounding
Electrode. A pole mount
Ray,
I believe that a pole-mounted or grounded-mounted PV array is considered
a structure and requires a ground electrode per 250.32. Perhaps the
exception would cover the possibility a installing very small system
without a ground electrode.
Kent Osterberg
Blue Mountain Solar, Inc.
Ray
)
together.
Kent Osterberg
Blue Mountain Solar, Inc.
toddc...@finestplanet.com wrote:
Does anyone know if it is
ok to use the rebar in a pole mount foundation as a ufer ground? I need
to ask the inspector too, but thought I'd ask
here first.
Todd
Jesse,
I use a Wiley WEEB 9.5 bonding washers between each module and rail, a
WEEB 6.7 lug on each rail, and a WEEB 6.7 on the pole.
Kent Osterberg
Blue Mountain Solar, Inc.
Jesse Dahl wrote:
Hello,
I have been looking at ground mount methods lately, specifically
the DPW Multi
that water will enter between the glass and frame, freeze,
and bow the frames. I think silicon sealant between the glass and frame
makes a more water tight seal.
Kent Osterberg
Blue Mountain Solar
Kirpal Khalsa wrote:
Happy Friday.so i was installing some sharp 240w
modules today and noticed
Brian,
Is this the drawing?
Magnum ac
coupled diagram from Google cache.
Kent Osterberg
Blue Mountain Solar
Allan Sindelar wrote:
Brian,
Good job of laying it out.
Now here's the part I'm missing. If as you say the grid-tied
inverter(s), either micro or string, are connected
) that may take many years to show up.
Kent Osterberg
Blue Mountain Solar
toddc...@finestplanet.com wrote:
Wrenches,
Fact or fiction: Adding concrete to the inside of a pole mount
pipe makes it stronger.
Thanks,
Todd
Sent from Finest Planet WebMail
ally the part about shorting the
array. Can anyone shed light on this?
Regards,
-Hans
From: re-wrenches-boun...@lists.re-wrenches.org
[mailto:re-wrenches-boun...@lists.re-wrenches.org]
On Behalf Of Kent Osterberg
Sent: Monday, July 18, 2011 10:07 PM
To: g...@icaruss
hat all dc loads may be energized to the potential of the PV array is
troubling. Especially with the possibility now of a 600-volt PV array
charging a battery system.
Kent Osterberg
Blue Mountain Solar
Hans Frederickson wrote:
Kent,
I'm not a geezer yet, but thanks
to my dad I doh
Gary,
No one else has come up with a 1987 NEC. If you can get a copy of 1987
section 690.5 (I think it was 690-5 back then), I'd appreciate it.
Kent Osterberg
Blue Mountain Solar
Gary Willett wrote:
Kent:
I am a member of the International Association of Electrical Inspectors
I'm looking for the text of 1987 NEC 690.5 to compare with 2011 version.
If any of you geezers have kept copies that old, please contact me off
list. Thanks.
Kent Osterberg
Blue Mountain Solar
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cuts of the Unistrut painted with galvanizing or stainless
paint?
Kent Osterberg
Blue Mountain Solar, Inc.
Gary Willett wrote:
It was brought to my attention that I had an error in my original post.
Here's the corrected text:
Fellow Wrenches:
I am involved in the commissioning of a 300kw
will handle the necessary current without a
heat sink.
Kent Osterberg
Blue Mountain Solar
Allan Sindelar wrote:
Phil and Wrenches,
Thank you for the response; good food for thought.
We looked at Aerovironment as a result of your suggestion, but it
appears to be out of production and unavailable
the power supply from pv to ac. The hard part may be locating
suitable relays. With a 100K buffer tank, exactness on the timing of
the switchover shouldn't be necessary.
Kent Osterberg
Blue Mountain Solar
Allan Sindelar wrote:
Wrenches,
A good client of ours is a rancher in the New Mexico
, in fact all the conductors, may be
energized in reference to ground. Use appropriate personal protective
gear.
Kent Osterberg
Blue Mountain Solar
Nick Vida wrote:
Hi wrenches.
I had an interesting case today that I have been thinking about since
it happened. I dont have all
inverter and the average loss for the system will be less, but it
shows that the ac wiring loss is a significant part of the discrepancy.
Also, even the revenue grade meter is not perfect - typically ±0.25%
when new.
Kent Osterberg
Blue Mountain Solar
m...@solar-energy-solutions.com wrote:
Mark
ahead of time should make this work smoothly.
Kent Osterberg
Blue Mountain Solar
Mark Frye wrote:
Thanks Nick,
250 talks about two seperate
buildings with one service, and 230 talks about one building with two
services.
I don't think this particular situation has
been
.
Kent Osterberg
Blue Mountain Solar
Mark Frye wrote:
Thanks Ken,
I still don't see any
configuration of equipment that would not involve making an electrical
connection between the two grounding systems of the two seperate
dwellings
In order to provide the required
GFP
to install
extra bracing underneath for almost every bracket. If working over an
insulated attic, you won't be able to install very far down from the
ridge.
Kent Osterberg
Blue Mountain Solar
penobscotso...@midmaine.com wrote:
Does anyone have experience mounting arrays on barns with 24"
two-pole safety switches that may be used to select ac or dc
power instead of the Grundfos switch. You might be pushing your luck
operating the pressure switch at 213 VDC.
Kent Osterberg
Blue Mountain Solar
Kirpal Khalsa wrote:
Hi allso I have a pumping project using a grundfos SQ
Flex pump
. Such
should be disclosed in any contract to install an off-grid power system.
Kent Osterberg
Blue Mountain Solar
Kristopher Schmid wrote:
I have an off-grid client who tells me that his clocks lose about 1 minute
per hour while he is running his backup generator. Has anyone seen this
before? Do
. Now the example doesn't resolve the limitation of backfeeding at
the main. Opps!
Kent Osterberg
Blue Mountain Solar
Jason Szumlanski wrote:
Another
key is to remember that this discussion also applies to the conductor
between the main panel and subpanel. In a large PV system
.
Kent Osterberg
Blue Mountain Solar
Al Frishman wrote:
Is
a monitoring system installed in the Load Center to measure the
cumulative kWhs of the inverters considered a load?
The
type of monitoring device I am talking about has CTs that go around
the conductors and the Voltage ref
and the inverters would have to feed the opposite end of
the bus bars. If no, the code is not clear on the requirement, but
obviously the 80-amp breaker in the main panel limits the maximum
current flowing through the sub-panel.
Kent Osterberg
Blue Mountain Solar
Al Frishman wrote:
Hi
to the utility side of the ATS, a service side tap wasn't
required. 2) The service disconnect switch had double lugs (not on my
sketch) so there weren't multiple conductor taps. While I only showed
one, this system actually had two non-essential panels: one for the
house and one for the barn.
Kent Osterberg
is
closed, what would stop power from flowing backwards through the
transfer switch?
Kent Osterberg
Blue Mountain Solar
wire...@gmail.com wrote:
This doesn't solve the reliability concern of a contactor
but on a webinar I heard a rep from Schneider say the XW (with GEN and
GRID AC IN's
Wrenches,
I noticed an error in my reply below when Allan's second comments
arrived. Correction: the battery is considered 100% discharged (not
80%) at 10.5 volts (1.75 vpc) under the conditions of use.
Kent
Kent Osterberg wrote:
William,
I'll try to add a little to Allan's
is off.
Kent Osterberg
Blue Mountain Solar
Mark Frye wrote:
Eric,
I do not have direct experience
with this but have been exploring the issue for a project I am
currently doing.
My response will be to take the
trouble to interconnect the Enphase inverters on the line side
is that routinely
charging to only 85% SOC will lead to sulfation problems. That can
shorten the battery life too.
Kent Osterberg
Blue Mountain Solar, Inc.
Allan Sindelar wrote:
William,
I use 80%, as the intent is that this is maximum, not typical. It's
directly used to calculate the battery
to return it after the solar maximum).
Kent Osterberg
Blue Moutain Solar, Inc
Allan Sindelar wrote:
For those of us less aware of solar flare issues and what we might
expect that relates to PV, could someone provide a good link to educate
us?
Thanks, Allan
Allan Sindelar
/08Murray_pdfs/08Murray_03/03_04-05.pdf
Kent Osterberg
Blue Mountain Solar
Carl Adams wrote:
Wrenches,
We often use a conventional 100A meter base and analog meter as an
independent metering system for inverter output. These meters
typically have a minimum conductor size of #6 AWG. For smaller
systems
Jay,
I've seen that happen. I concluded that it was associated with an AGS
fault status. I also reset the Mate to factory defaults and reprogrammed
all the AGS settings for the customer. No problem since then.
Kent Osterberg
Blue Mountain Solar, Inc.
jay peltz wrote:
HI All,
I'm curious
Larry,
You aren't the only one offended. It gives the impression that only
NABCEP certified installers are competent, which isn't true. And that
every NABCEP certified installer will do a competent job; also not a
guaranteed outcome.
Kent Osterberg
Blue Mountain Solar, Inc.
wire
,
and there would be no voltage or resistance external to the module -
but it would still exist within the module.
Kent Osterberg
Blue Mountain Solar, Inc.
Greg Egan wrote:
Fellow Scientists,
I got in a discussion with a wrench the other day. He is under the
impression that when a PV module
for that
purpose, but the breaker in the main panel may be sufficient.
Kent Osterberg
Blue Mountain Solar, Inc.
Aaron Mandelkorn wrote:
It seems as though almost every utility has a different
requirement concerning Utility External Disconnects and the AC
disconnects for the PV system in general. Some
. Pushing the limits, the way we do,
gets us in trouble.
Kent Osterberg
Blue Mountain Solar, Inc.
Starlight Solar, Larry Crutcher wrote:
I believe the issue we had has to do
with using the Sanyo high voltage PV module. As Kent points out, we
were operating the controller at the design
I've got customers using the Onan 1800-rpm liquid-cooled 20-KW and
30-kW LP residential generators without any problems. While Onan
doesn't exclude off-grid use, the warranty
is only 1-year 1000-hours for off-grid applications.
Kent Osterberg
Blue Mountain Solar, Inc.
Randy Brooks wrote
not go high enough for the inverter to max out. In the hot weather
when the sun angle is optimum for a 20 degree roof, the module output
will be down. How much solar is reasonable to put on the inverter
depends on the circumstances.
Kent Osterberg
Blue Mountain Solar, Inc.
Darryl Thayer wrote
Nick,
Could you post a diagram showing when a male whip is useful? I'm
having a really hard time envisioning a need for one.
Kent Osterberg
Blue Mountain Solar, Inc.
Nick Soleil wrote:
William:
Your diagram is one way to do it, in fact, I always divide my
circuits into 2 sub
. And there are other options too.
It does still make sense that Enphase doesn't endorse cutting the
extension for that purpose.
Kent Osterberg
Blue Mountain Solar, Inc.
Nick Soleil wrote:
Sorry
Kent:
I am just not that motivated by this conversation to create
drawings. I will try to explain one
Eric,
Why doesn't a female whip (the standard Enphase branch circuit kit
component) work? Seems like both subarrays should have a female whip
going to a SolaDeck. Then from both SolaDecks to a j-box in the attic.
Kent Osterberg
Blue Mountain Solar.
Eric Thomas wrote:
I know its a funny
different at another elevation, it would be
different with a different array angle, ..., and the module tolerance
and inverter efficiency also effect the results. Modules in this
system are Suntech 170-watt +/-3%. The inverter is Sunnyboy 1800 that
should be operating at close to 93% efficiency.
Kent
.
Kent Osterberg
Blue Mountain Solar
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John.
I've used AEE
Solar's corrugated roof block with good success. Since the
corrugations rarely line up with structural members you'll need to
install blocking for most attachment points.
Kent Osterberg
Blue Mountain Solar
cvso...@aol.com wrote:
Wrenches,
Do you have any tips
Wrenches,
I've got a customer that has a dual Xantrex TR2424 inverter system (not
my installation) that complains of blinking lights in the house. Anyone
have similar issues associated with these inverters? Any solutions?
Kent Osterberg
Blue Mountain Solar
Dave,
The flickering is subtle, but it occurs all of the time.
Kent Osterberg
Blur Mountain Solar
Dave Palumbo wrote:
Kent,
Is this a flickering of the lights when the generator is running and
charging the battery bank? Which I have seen.
Or, something that is going on all the time? Which
charge in the system you are considering, a voltage controlled switch,
like the Morningstar relay driver, could simply shut down the SB3000.
Kent Osterberg
Blue Mountain Solar
Howie Michaelson wrote:
Hi All,
I have done several AC coupled off-grid systems using Sunny Islands and
Sunny Boys
are (nearly) full, the Sunny boy must be
shut down. A voltage controlled switch or the FX inverter's Aux output
can open a relay to remove power from the Sunny Boy.
Kent Osterberg
Blue Mountain Solar
Doug Wells wrote:
Wrenches,
Howie, good to see you probing this issue.
I have an upcoming system
. Unfortunately, there isn't a good way to turn the generator
off - that function is also a simple voltage trigger and time delay.
Kent Osterberg
BLue Mountain Solar
penobscotso...@midmaine.com wrote:
Can anyone point me in the direction of a good, autonomous generator auto
start. We have
be largely uncertainty in the accuracy of the flash
test equipment, procedures, and in how the flash test correlates to the
real world. In other words it is a CYA operation.
Kent Osterberg
Blue Mountain Solar
Marco Mangelsdorf wrote:
SolarWorld is pushing hard its 245-watt module
Marco,
This may be what you are looking for:
http://rredc.nrel.gov/solar/calculators/PVWATTS/version1/derate.cgi
Kent Osterberg
Blue Mountain Solar
Marco Mangelsdorf wrote:
Could someone please provide me with that
generally accepted
equation when it comes to estimating AC
Marco,
Just playing around with these factors a bit shows you can get 90%, if
the modules have -0% tolerance and they are spotless clean.
Kent
Kent Osterberg wrote:
Marco,
This may be what you are looking for:
http://rredc.nrel.gov/solar/calculators/PVWATTS/version1/derate.cgi
so it takes a while to upload or
download.
Kent Osterberg
Blue Mountain Solar, Inc.
Eric Thomas wrote:
Hey there,
We have a string inverter system installation coming up that has a
power line suspended over the roof. The line is diagonal to the roof
and about 20' above the surface
the fault to one
string. If a GFP is installed, any arc may be terminated, or depending
on the fault maybe not.
Kent Osterberg
Blue Mountain Solar, Inc.
Matt Lafferty wrote:
Kent, William, Nick, Dave,
et al,
Wish I had time to respond
sooner than this,but haven't. Where to start
, the wire will probably block a little less light. But a 50%
reduction in the light on a few cells will probably reduce the entire
module output by 50%. A shadow every day for the hours you are talking
about sounds like a pretty serious issue.
Kent Osterberg
Blue Mountain Solar
benn kilburn wrote
on energy production depends on how large the
shadow is, how long it lasts, and what hours it occurs.
Kent Osterberg
Blue Mountain Solar
Nick Soleil wrote:
Hi
Kent:
I am sure that aerial wires have very little impact on system
outputs. I just checked the Enphase Enlighten data for a system I
the
protection that is needed. The existing ground fault protection in the
inverters is inadequate and current plans for arc fault protection may
not be a satisfactory either. These have been slow incremental
improvements; much more is needed.
--
Kent Osterberg
Blue Mountain Solar
541-568-4882
PV systems
with fuses. What's needed is a ground fault protector/arc fault
protector that is located in the combiner box. Until that exists, the
feeder between the combiner and inverter needs to be considered an
unfused conductor.
Kent Osterberg
Blue Mountain Solar
Matt Lafferty wrote:
power system such as portable generator with no neutral
ground bond, a GFCI won't trip because there is too much impedance
between neutral and ground.
Kent Osterberg
Blue Mountain Solar
Darryl Thayer wrote:
Just a note, FYI
The GFCI will work without a ground, it operates
is normally required for 15 and 20-amp outlets on
portable generators. But then a GFI wouldn't work without a
neutral-ground bond anyway. There is no sign of a UL listing, but mine
has a sticker from the City of Los Angeles saying that it is "approved
for use".
Kent Osterberg
Blue Moun
Kirk,
The problem may be related to the transfer delay. The default time is
way too long. Try reducing it to 10 cycles or even less.
Kent Osterberg
Blue Mountain Solar
Kirk Herander, VSE wrote:
Hello,
I have an off-grid customer with dual Outback
inverters and
a Kohler
Years ago, I used to get custom cases made by Silton Company. They are
now owned by Olympic Case Company
but the facility in Fresno is still in use.
Kent Osterberg
Blue Mountain Solar
Peter Parrish wrote:
I seem to remember reading about a source of "custom padded equipment
is forward, left is
backwards.
Kent Osterberg
Blue Mountain Solar
Gary Easton wrote:
Hello,
I am having trouble metering a system with an Outback 3648 serving a
protected loads panel. I need a way to accurately measure the production.
I have a dual stator 12s meter installed with the &qu
Jeff,
I think this is exactly what you are describing:
http://www.aeesolar.com/PDFs/SnapNrack-Tech-Bulletin-CRB_7-23-09.pdf
Kent Osterberg
Blue Mountain Solar
Jeff Yago wrote:
Most of the past metal roof projects we have completed worked great with S-5! clamps. However, we have
Mark,
Do the interconnects total the same length in each string? There could
be a bad connection somewhere in that string. But more than likely
this behavior is the result of a cell (or cells) that has a high
impedance because it is sulfated. How do the specific gravity numbers
look.
Kent
. If you can buy and install PV for much less than
that, how can you justify such little gain from the extra wire cost? 2
or 3 AWG may be worth it, but it sure doesn't look like 1 AWG is a
smart choice.
Kent Osterberg
Blue Mountain Solar
Dana wrote:
Ray,
The
$ could be making
August,
You might also consider the Contico Pro Tuff Bin. $85 from Grainger.
http://www.grainger.com/Grainger/items/1RG71
It also holds four L-16 batteries. You do have to keep the cables
short and low though.
Kent Osterberg
Blue Mountain Solar
Joel Davidson wrote:
Hi August
below 50% DOD. Looking at this data makes me question that
practice. It also makes me wonder about the seven-year warranty. Even
with 20% daily discharge it looks like the batteries should be spent in
about four years. Any suggestions on how to get seven years of service
from a set of L-16s?
Kent
coincides with the rafter or truss
location.
Kent Osterberg
Blue Mountain Solar, Inc.
Drake Chamberlin wrote:
At 01:16 PM 6/24/2010, you wrote:
Oregon rebate programs (where we are based) are requiring all roof
penetrations/attachments to be flashed.
What do you use to flash metal roofs
I recently talked to the tech support folks at Magnum about AFCI
breakers and they didn't know of a single one that would work with
modified square wave inverters. The AFCI requirement for all new
residential construction may finally be the death of modified square
wave inverters.
Kent
still says don't open under load. Fortunately
that isn't a serious problem because the dc current should be zero if
the ac power is disconnected. But that is ignoring the possibility of
a dc short circuit in the inverter.
Kent Osterberg
Blue Mountain Solar
Marv Dargatz wrote:
Kent,
The
Kirpal,
None of the SQFlex equipment is UL listed. You may find that your AHJ
won't approve any of the SQFlex controls and possibly not even the pump.
Kent Osterberg
Blue Mountain Solar
Kirpal Khalsa wrote:
Hi Folks.I am working on putting together a domestic
water pumping system using
or of
the first microinverter in a branch circuit is suitable as a
disconnecting means once the AC branch circuit breaker in the load
center has been opened."
Sorry, but that's just not a clear a set of instructions yet. Can we
open these connectors under load or are we never supposed to open them
under l
failure for the
same customer. The pump is in a deep well that it is unlikely to over
pump and there is a low-water sensor too. For those of you that have
installed these pumps, what types of problems have you observed? How
long are these pumps lasting? Thanks any replies.
Kent Osterberg
Blue
. PF = W/VA = W/sqrt(W^2+VAR^2). Reduce W without changing VAR
and the power factor goes down, possibly even to zero.
Kent Osterberg
Blue Mountain Solar
toddc...@finestplanet.com wrote:
I have a question about my
personal home system. It is an Outback battery based grid tie. My
digital utility
Marco,
Take a look at 2008 NEC 310.15(4)(a). The neutral conductor isn't
counted for the purpose of NEC 310.15(B)(2)(a) when it is part of a
circuit where it only carries the unbalanced current.
Kent Osterberg
Blue Mountain Solar
Marco Mangelsdorf wrote:
Thanks
or heavy polyethylene pond liner on the
bottom and up the sides 4 to 6 inches.
Kent Osterberg
Blue Mountain Solar
Mick Abraham wrote:
Hi, Mechanix~
My "customer du monde" has a dirt floor in the battery space but he's
willing to build something on which we could place his
Ray,
I haven't installed any HUP batteries in several years so my info may
be out of date but the steel case on the older HUP batteries had drain
holes on the bottom.
Kent Osterberg
Blue Mountain Solar, Inc.
R Ray Walters wrote:
I haven't seen a problem with concrete, but wood
definitely
on a generator or solar system. To turn them off, a 2-gallon
pressure tank with pressure switch (adjusted to operate at 10 psi)
works great if the PV array is near the pumping system.
Kent Osterberg
Blue Mountain Solar, Inc.
Allan Sindelar wrote:
Jeff,
What are the brands and specs
David,
Sq D doesn't have them UL listed for it but they self certify the 10 to
30 amp 2-pole breakers for 125 volts dc. Problem is: if you need a UL
listing, you are stuck at 48 volts.
Kent Osterberg
Blue Mountain Solar, Inc.
David Katz wrote:
Allan,
Are you running 100+ volts DC
/
..
-
Original Message -
From:
Kent Osterberg
To:
Wrenches
Sent:
Saturday, April 10, 2010 9:22 AM
Subject:
[RE-wrenches] DC wire sizing
Here's my challenge to all of you that want to design for 1% or 1.5%
voltage drop all the time:
Take a 50-ft circuit
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