[RE-wrenches] Electric car chargers

[frenergy]

William,

   I would have to concur with Randy's chart pretty much.  A couple 
months a go we bought a 2012 Toyota RAV4 EV.  I had just recently completed 
an upgrade system here (4.5KW PV, Classic, 84 KW of Rolls batts and a 
Radian).  We are off-grid.


   The research I did before purchasing our charger is the currently 
available chargers max at 7.7 KW.  Almost all of the level II chargers (240 
volt) charge at one rate...I was able to find a charger made by Siemens that 
has an adjustable charge rate which has proved very valuable being off-grid 
(EG: varying solar resource, charging window, departure time, battery temp, 
SOC, etc).


   I'm not sure if there is any effort to market a residential charger 
that will put out more than 7.7KW.


Bill
Feather River Solar Electric
Taylorsville, CA


- Original Message - 
From: "William Miller" 

To: "RE-wrenches" 
Sent: Friday, February 22, 2013 4:29 PM
Subject: [RE-wrenches] Electric car chargers



Friends:

I would not bother this group with a question I could easily answer for 
myself with a little research.  I thought I could find the answer to this 
question on line but it has been very elusive:


Does anyone know the ratings for the available high power electric car 
charger?


Thanks in advance.


William Miller









































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

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Re: [RE-wrenches] Electric car chargers

[Randy Brooks]

William,

I found this on Wikipedia:
Level   Original definition[195]Coulomb Technologies' definition[196]   
Connectors
Level 1 AC energy to the vehicle's on-board charger; from the most common U.S. 
grounded household receptacle, commonly referred to as a 120 volt outlet.   
 120 V AC; 16 A (= 1.92 kW)  SAE J1772 (16.8 kW),
NEMA 5-15
Level 2 AC energy to the vehicle's on-board charger;208 - 240 volt, single 
phase. The maximum current specified is 32 amps (continuous) with a branch 
circuit breaker rated at 40 amps. Maximum continuous input power is specified 
as 7.68 kW (= 240V x 32A*). 208-240 V AC;
12 A - 80 A (= 2.5 - 19.2 kW)   SAE J1772 (16.8 kW),
IEC 62196 (44 kW),
Magne Charge (Obsolete),
Avcon,
IEC 60309 16 A (3.8 kW)
IEC 62198-2 Type2 same as VDE-AR-E 2623-2-2, also known as the Mennekes 
connector (43.5 kW)IEC 62198-2 Type3 also known as Scame
Level 3 DC energy from an off-board charger; there is no minimum energy 
requirement but the maximum current specified is 400 amps and 240 kW continuous 
power supplied. very high voltages (300-600 V DC); very high currents (hundreds 
of Amperes) Magne Charge (Obsolete)
CHΛdeMO (62.5 kW), SAE J1772 Combo, IEC 62196 Mennekes Combo
.* or potentially 208V x 37A, out of the strict specification but within 
circuit breaker and connector/cable power limits. Alternatively, this voltage 
would impose a lower power rating of 6.7 kW at 32A.

Is this what you're looking for?  My Nissan Leaf came with a Level 1 adapter 
cord to plug into any standard 120v outlet.  I installed a Level 2 charger in 
my garage, 240v/30 amp.  The car also has a Level 3 charging port that I've 
used several times at public Level 3 charging stations.

Randy Brooks
Brooks Solar, Inc.
Solar Power for People
140 Columbia View
Chelan, WA  98816
509-682-9646
ra...@brookssolar.com
www.BrooksSolar.com

On Feb 22, 2013, at 4:29 PM, William Miller  wrote:

> Friends:
> 
> I would not bother this group with a question I could easily answer for 
> myself with a little research.  I thought I could find the answer to this 
> question on line but it has been very elusive:
> 
> Does anyone know the ratings for the available high power electric car 
> charger?
> 
> Thanks in advance.
> 
> 
> William Miller
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Miller Solar
> Voice :805-438-5600
> email: will...@millersolar.com
> http://millersolar.com
> License No. C-10-773985
> 
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Re: [RE-wrenches] Electric car chargers

[Ray Walters]

http://nationalcarcharging.com/downloads/

has several models of 240 vac chargers with full spec sheets.  I just 
met them at a trade show.


R.Ray Walters
CTO, Solarray, Inc
Nabcep Certified, Licensed Contractor
808 269-7491

On 2/22/2013 5:29 PM, William Miller wrote:

Friends:

I would not bother this group with a question I could easily answer 
for myself with a little research.  I thought I could find the answer 
to this question on line but it has been very elusive:


Does anyone know the ratings for the available high power electric car 
charger?


Thanks in advance.


William Miller









































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

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Re: [RE-wrenches] Electric car chargers

[Ray Walters]

Hi William:

I'm working on an off grid charging station for a Chevy Volt.  I decided 
to stick with the onboard  120 VAC charger, as the slower charge rates 
are more efficient for both the house and vehicle batteries.  Its the 
old Puekert's # issue: the faster the charge or discharge rate, the 
higher the losses.
The Chevy 120 vac on board charger  maxes at about 12 amps x 120 vac.  
Sorry, if that didn't directly answer your question, but hopefully was 
still helpful.


R.Ray Walters
CTO, Solarray, Inc
Nabcep Certified, Licensed Contractor
808 269-7491

On 2/22/2013 5:29 PM, William Miller wrote:

Friends:

I would not bother this group with a question I could easily answer 
for myself with a little research.  I thought I could find the answer 
to this question on line but it has been very elusive:


Does anyone know the ratings for the available high power electric car 
charger?


Thanks in advance.


William Miller









































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

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[RE-wrenches] Electric car chargers

[William Miller]

Friends:

I would not bother this group with a question I could easily answer for 
myself with a little research.  I thought I could find the answer to this 
question on line but it has been very elusive:


Does anyone know the ratings for the available high power electric car charger?

Thanks in advance.


William Miller









































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

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Re: [RE-wrenches] Remote Sunny boy Monitoring

[Dan Fink]

I'm a beginner on wireless networks and RS485.
But I can say that once you get it on wireless LAN, it's cheap and
easy for even a novice to do amazing things. We have a Ubiquiti
nano-bridge M2 set up just for internet to our remote "dorm" cabin for
students when we do workshops.

The line of sight window is better when wider of course; but there are
also 900 mhz bridges same brand and model that work a little better
around obstructions, and antenna solutions are important
too..maybe a more omni at the backhaul, more directional from the
remote location.

Anyway -- once it's on LAN, Cat5 and wifi you caqn do about anything with it.

-- 
Dan Fink,
Executive Director;
Otherpower
Buckville Energy Consulting
Buckville Publications LLC
NABCEP / IREC accredited Continuing Education Providers
970.672.4342 (voicemail)
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Re: [RE-wrenches] Remote Sunny boy Monitoring

[John Berdner]

I have used both 900 Mhz and 2.4 Ghz Wifi with mixed results through trees.
In the past we used Moxa wireless RS-485 bridges which were 900 Mhz devices.
The lower frequency tends to work better with obstructions but not sure about 
over the top of a hill.
Depends on how far over the hill you are.

Do you have access to the hill top ?
If yes, using a directional antennas and a passive repeater (back to back 
directional antennas) at the hill top to bend the signal.
If you go this way then you probably want to go with 2.4 Ghz since you will 
need multiple high gain antennas.
You will read much pros and con debate about if passive repeaters do or do not 
work.
With short path lengths, short coax trimmed for low VSWR and very high gain 
directional antennas it can.
I have done it successfully in the past and it worked better than the 
calculations would indicate.

There are multiple suppliers of directional 2.4 Ghz antennas.
Here is a link to a 24 dB antenna from a local CA retail electronics house.
http://www.frys.com/product/7411495;jsessionid=5vsRnGBpd1iiZqjr7HmfLg__.node2?site=sr:SEARCH:MAIN_RSLT_PG

Best Regards,

John Berdner
General Manager, North America



SolarEdge Technologies, Inc.
3347 Gateway Boulevard, Fremont CA 94538 USA  (*Please note of our new address.)
T: 510.498.3200, X 747
M: 530.277.4894


-Original Message-
From: re-wrenches-boun...@lists.re-wrenches.org 
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of William Miller
Sent: Friday, February 22, 2013 1:35 PM
To: RE-wrenches
Subject: Re: [RE-wrenches] Remote Sunny boy Monitoring

Steve, Ryan:

I don't quite have line of sight.  There is the brow of a hill...  I will look 
to see if any of the wireless solutions will handle this scenario.

Wm


At 12:57 PM 2/22/2013, Steve Jefferson wrote:
>Content-Language: en-US
>Content-Type: multipart/alternative;
>
>boundary="_000_41FE255D65D554478C3B17F3EB5410EF5768618DSVRUSEXMBX01sma_"
>
>There is a company called Digi.com. they make a wireless bridge for the
>RS-485 protocol. Needs to be line of sight, but it will travel about 1000'.
>
>They are familiar with installers using their radios to communicate
>with our inverters, set up is pretty straight forward.
>
>I am looking for a part number.
>I have a couple of systems from my install days with these being used.
>
>I like Ryan's solution as well.

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Re: [RE-wrenches] Remote Sunny boy Monitoring

[Kevin Pegg]

Hi William, 

I have successfully used this product below on a few installs without line of 
sight, trees, hills, etc in the way approx 1 km span doing exactly what you are 
asking for - wireless RS485. It costs more than WiFi bridges, but it also 
works! 

http://www.bb-elec.com/Products/Wireless-Cellular/Radio-Modems/Industrial-Grade-Radio-Modems.aspx
Specifically, the LR-KIT, at 900MHz is better for marginal sites, coupled with 
external antennas and quality cable. Don't skimp! I used a Yagi antenna on the 
webbox side to transmit, with an omni antenna on the receiving end. Line them 
up as best you can and spend a bit of time adjusting until there's a signal. 

Once we got the units talking it's been 100% uptime for at least 2 years now. 
This company has all sorts of neat network products that I have been using for 
over a decade. Amazingly solid industrial quality gear. I believe they have a 
wireless AC relay solution as well I saw people asking in another thread. I 
never ended up deploying, but they had an easy off-the-shelf solution for a 
wireless gen start signal retrofit where pulling cable wasn't going to happen. 

Kevin

-Original Message-
From: re-wrenches-boun...@lists.re-wrenches.org
[mailto:re-wrenches-boun...@lists.re-wrenches.org]On Behalf Of William
Miller
Sent: February 22, 2013 10:20 AM
To: RE-wrenches
Subject: [RE-wrenches] Remote Sunny boy Monitoring


Friends:

Thanks for the responses to my question.  Here is what I have learned:

The main problem is that the Sunny Boy is remote from the house and there 
is no signal conduit.  There are any number of monitors that can hard wire 
to the Sunny Boy, usually with an RS485 connection.

Without a hardwire path that solution is not so easy.  Apparently I need to 
asses the viability of a wireless RS485 system.

I am wondering:

1. Do I understand the above scenario correctly?
2. Do any of you have any experience with wireless 485 systems?

Thanks again for all of the help.

William Miller


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

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Re: [RE-wrenches] Remote Sunny boy Monitoring

[toddcory]

i have set up wireless bridges for ip to remote locations and my experience 
with this has me leaning towards "no dice" william. 

these links run in the 2.3 gHz and up range which is line-of-sight only. trees 
will even attenuate the signal, so total blockage with the earth looks grim.
 
have a great weekend everyone!
 
todd
 
 
 
 
 
 
On Friday, February 22, 2013 1:34pm, "William Miller"  
said:



> Steve, Ryan:
> 
> I don't quite have line of sight.  There is the brow of a hill...  I will
> look to see if any of the wireless solutions will handle this scenario.
> 
> Wm
> 
> 
> At 12:57 PM 2/22/2013, Steve Jefferson wrote:
> >Content-Language: en-US
> >Content-Type: multipart/alternative;
> >
> >boundary="_000_41FE255D65D554478C3B17F3EB5410EF5768618DSVRUSEXMBX01sma_"
> >
> >There is a company called Digi.com. they make a wireless bridge for the
> >RS-485 protocol. Needs to be line of sight, but it will travel about 1000'.
> >
> >They are familiar with installers using their radios to communicate with
> >our inverters, set up is pretty straight forward.
> >
> >I am looking for a part number.
> >I have a couple of systems from my install days with these being used.
> >
> >I like Ryan's solution as well.
> 
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Re: [RE-wrenches] Remote Sunny boy Monitoring

[Steve Jefferson]

If that is the case, there are some Ethernet bridges that will work. 
Depending on distance, you would need to buy a set with either adjustable power 
or know the exact range.
I have a security camera set up I used a set on, had adjustable power setting. 
Works great. Adjusting the power adds "bend" to the signal.

You might want to give digi a call, they have many solutions for things like 
this.

SMA America, LLC
Steve Jefferson
Supervisor, Service Line
6020 West Oaks Blvd, Suite 300
Rocklin, CA 95765 - 3714
U.S.A.
Tel:  +1 916 625 0870
Fax: +1 916 624-2445
Service Line +1 877 697 6283 (Toll Free)
Email: steve.jeffer...@sma-america.com
www.SMA-America.com
 
This email and any attachments thereto may contain SMA America, LLC 
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-Original Message-
From: re-wrenches-boun...@lists.re-wrenches.org 
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of William Miller
Sent: Friday, February 22, 2013 1:35 PM
To: RE-wrenches
Subject: Re: [RE-wrenches] Remote Sunny boy Monitoring

Steve, Ryan:

I don't quite have line of sight.  There is the brow of a hill...  I will look 
to see if any of the wireless solutions will handle this scenario.

Wm

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Re: [RE-wrenches] Remote Sunny boy Monitoring

[William Miller]

Steve, Ryan:

I don't quite have line of sight.  There is the brow of a hill...  I will 
look to see if any of the wireless solutions will handle this scenario.


Wm


At 12:57 PM 2/22/2013, Steve Jefferson wrote:

Content-Language: en-US
Content-Type: multipart/alternative;

boundary="_000_41FE255D65D554478C3B17F3EB5410EF5768618DSVRUSEXMBX01sma_"

There is a company called Digi.com. they make a wireless bridge for the 
RS-485 protocol. Needs to be line of sight, but it will travel about 1000'.


They are familiar with installers using their radios to communicate with 
our inverters, set up is pretty straight forward.


I am looking for a part number.
I have a couple of systems from my install days with these being used.

I like Ryan's solution as well.


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Re: [RE-wrenches] Remote Sunny boy Monitoring

[Steve Jefferson]

There is a company called Digi.com. they make a wireless bridge for the RS-485 
protocol. Needs to be line of sight, but it will travel about 1000'.

They are familiar with installers using their radios to communicate with our 
inverters, set up is pretty straight forward.

I am looking for a part number.
I have a couple of systems from my install days with these being used.

I like Ryan's solution as well.

SMA America, LLC
Steve Jefferson
Supervisor, Service Line
6020 West Oaks Blvd, Suite 300
Rocklin, CA 95765 - 3714
U.S.A.
Tel:  +1 916 625 0870
Fax: +1 916 624-2445
Service Line +1 877 697 6283 (Toll Free)
Email: steve.jeffer...@sma-america.com
www.SMA-America.com

This email and any attachments thereto may contain SMA America, LLC 
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[RE-wrenches] Remote Sunny boy Monitoring

[William Miller]

Friends:

Thanks for the responses to my question.  Here is what I have learned:

The main problem is that the Sunny Boy is remote from the house and there 
is no signal conduit.  There are any number of monitors that can hard wire 
to the Sunny Boy, usually with an RS485 connection.


Without a hardwire path that solution is not so easy.  Apparently I need to 
asses the viability of a wireless RS485 system.


I am wondering:

1. Do I understand the above scenario correctly?
2. Do any of you have any experience with wireless 485 systems?

Thanks again for all of the help.

William Miller


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

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Re: [RE-wrenches] Snow loads

[Gary Bassett]

Jeffrey,

I agree. We do structural analysis on every roof design and factor in the point 
loading at the attachment points. I had floated this idea because it came from 
an SE that I work with that also has a PV system. His theory is the definition 
snow loads are accumulation of snow over time. And most of the time snow will 
slide off the panels in 3-4 days. The panels would have to be placed so the 
snow would completely slide off the roof. I wanted to see what others thought 
of this approach who have been doing structural analysis. I appreciate your 
responses.

Gary


From: re-wrenches-boun...@lists.re-wrenches.org 
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of JRQ
Sent: Thursday, February 21, 2013 8:28 PM
To: RE-wrenches
Subject: Re: [RE-wrenches] Snow loads

Gary,

The snow loads that structural engineers design to are a worst-case scenario. 
It is true that snow tends to slough off of PV arrays quicker than your normal 
roof. However, if there is a major snow event, especially if it starts at night 
(this recent blizzard on the East Coast would be a good example), snow will 
build up on the array the same as it does everywhere else.

In many cases, a PV array actually makes the engineering assumptions worst. Any 
snow that lands on the modules transfers down to the attachments, and 
point-load the structural members. The weight of the snow is less distributed 
when it sits on a PV array, placing additional stress on individual members. I 
work in Massachusetts currently, and we often have to perform rafter upgrades 
to roofs that are fine otherwise for exactly this reason.

If you have any snow load requirements in your area, I would highly recommend 
you have a structural engineer review the structure, even if a structural stamp 
is not required.

Jeffrey Quackenbush



From: Bob-O Schultze 
mailto:bo...@electronconnection.com>>
To: RE-wrenches 
mailto:re-wrenches@lists.re-wrenches.org>>
Sent: Tuesday, February 19, 2013 3:00 PM
Subject: Re: [RE-wrenches] Snow loads

I would certainly agree with Will here. You can't make that argument as stated, 
it's wrong. Please don't try to make it to your AHJ, you take the chance of 
f-ing it up for everyone around there. I think the best argument you can try 
is:  aside from the usual 3-4lbs/sq/ft that the array itself ads to the roof 
load, snow will be very unlikely to build up on the modules to the degree that 
it builds up anywhere else on the roof. The freezing-rain-before-a-snow 
phenomena is very real and it WILL happen sooner or later. Not often perhaps 
and under most conditions the snow will leave the modules before the roof. 
But...Gotta be real about that.
Bob-O Schultze


On Feb 19, 2013, at 11:06 AM, Will White wrote:


Most structural engineers I’ve seen take a reduction for slippery surface but I 
think you’d be stretching things to say adding PV panels reduces the load to 
zero.  I have a 45 degree pitch roof and I get snow build up some times 
especially if we get freezing rain before the snow.

Also if you have an asphalt shingle roof you can create an unbalanced load with 
snow sliding off the south side and sticking on the north side.  Most engineers 
take this into consideration too.

Thanks,
Will

__
Will White
Regional Field Operations Manager – New England

Real Goods Solar
64 Main St.
Montpelier, VT 05602
Tel: (802) 223-7804
Cell: (802) 234-3167
www.realgoodssolar.com





From: 
re-wrenches-boun...@lists.re-wrenches.org
 [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Gary Bassett
Sent: Tuesday, February 19, 2013 1:48 PM
To: re-wrenches@lists.re-wrenches.org
Subject: [RE-wrenches] Snow loads

Has anyone in the snow belt areas have any luck with convincing their local 
building inspectors that the snow melts or slides from panels, much like a 
metal roof only better. Thus your snow load would be reduced to zero where the 
panels have been installed.

Gary


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