Re: [RE-wrenches] Rapid Shutdown Compliance

[cwarfel]

I live in a small town, so our outreach probably has greater impact. We
have gone to the FD meetings, we tell them about the system types and
definitions, quiz them and follow up.   So, I think depending upon
training, which is not a one shot deal, it can have an impact. They seem
relieved.

On 2020-05-07 11:39, Brian Mehalic wrote:

> I agree: utilize the formal process, ideally with a group of folks.  If you 
> are a SEIA member, get involved in their Codes and Standards process.  The 
> additional directory language you suggest is not likely to be valuable to 
> many first responders without significant training and documentation, and 
> even then is still likely to get "lost" amongst other labels and directories. 
> RS as required now instead focuses on an initiation device(s), so that the 
> device is all responders need to look for - it's up to the installer to 
> specify and put in the correct gear to make RS happen, and the AHJ to verify 
> this.
> 
> Brian Mehalic 
> NABCEP Certified Solar PV Installation Professional(tm) R031508-59 
> National Electrical Code(R) CMP-4 Member 
> (520) 204-6639
> 
> Solar Energy International
> http://www.solarenergy.org 
> 
> SEI Professional Services 
> http://www.seisolarpros.com [1] 
> 
> On Thu, May 7, 2020 at 6:43 AM Christopher Warfel 
>  wrote: 
> 
> I believe Rapid Shutdown was mostly a solution looking for a problem.   The 
> only way I see this becoming "reasonable" is to present "grievances" to the 
> Code Making Panel WITH a solution for their consideration.  Based on 
> experience from being part of an outreach program that taught approximately 
> 10k firefighters over four years, I have asked that they add to the 
> Directory, the language that states what type of solar electric system is on 
> site (Microinverter, dc optimizer, string, multimode, grid isolated) so that 
> First Responders don't have to guess.  I realize this is different than MLPE, 
> but it targets the person who Rapid Shutdown came into being for, and that 
> was the First Responder.   Chris 
> 
> On 5/6/2020 10:37 PM, Ray wrote: 
> 
> Spending more time on the roof, while putting more equipment and parts to 
> meet MLPE, means more trips up the ladder, which increases, not decreases the 
> #1 worker safety danger: Falls.  Please correct me if I have somehow 
> misunderstood this, but MLPE is not making installers safer based on OSHA 
> information provided.   Also after installation, which system is more likely 
> to require workers to return to work on the roof, pulling up modules, trying 
> to find problem equipment?  More connections is More safe?  Really?  I 
> haven't had to climb back up on the roof on any of my older, lower voltage 
> off grid work in almost a decade. 
> 
> Once again, MLPE has its place, (larger systems, multiple subarrays, higher 
> voltage) but we should have sensible exemptions as have been mentioned 
> already.  We are endangering ourselves and our employees needlessly, to 
> comply with 690.12.  
> 
> Ray Walters
> Remote Solar
> 303 505-8760
> 
> On 5/6/20 8:41 PM, drake.chamber...@redwoodalliance.org wrote: 
> 
> Interestingly enough, the data on the link [2] provided shows accidents from 
> gas explosions, falls, health problems and  industrial injuries. None of 
> these incidents could have been prevented by module level power electronics. 
> This is typical of the data that I've seen so far.
> 
> ---
> 
> On 2020-05-06 17:22, Martin Herzfeld wrote: 
> 
> There could be an issue of encouraging MLPE for worker safety? 
> 
> 1.  This is data involving incidents with workers in the OSHA Fatalities and 
> Catastrophe Investigation Summaries found here: 
> https://www.osha.gov/pls/imis/AccidentSearch.search?p_logger=1&acc_description=&acc_Abstract=solar&acc_keyword=&sic=&naics=&Office=All&officetype=All&endmonth=05&endday=05&endyear=2002&startmonth=05&startday=05&startyear=2021&InspNr=
>  
> 
> 2.  In the past I've observed an arc fault at the module level with 
> traditional string systems without a listed arc-fault circuit interrupter 
> NEC/CEC 690.11. The function in NEC/CEC 690.12 would be - to reduce the shock 
> hazard - for _emergency responders_ or _firefighters? (NEC 2020)._  However, 
> I've observed thermal events in the panelboard with plans and workmanship 
> issues.  
> 
> On the other hand, falls are the #1 reason for incidents in the construction 
> industry.  
> 
> All the best, 
> 
> Martin Herzfeld, Interstate Renewable Energy Council (IREC) Certified Master 
> Trainer (tm) for Photovoltaics (PV) Installation Professional #IREC 10037
> Contract Training Provider (CTP)
> Adjunct Professor, Energy
> 
> California Solar & Electrical Contractor License  #00833782  C46, C10, D56, 
> D31, C-7 - Since 2004
> Solar, Electrical, Trenching, Pole Installation & Maintenance, Instrumentation
> 
> Contract Solar (PV) Technical Inspector - 3rd Party Inspections 
> Underwriters Laboratories (UL) Certified PV Installer #17, OSHA 30
> OSHA-Authorize

Re: [RE-wrenches] Fwd: Neutral Sizing 705.95

[Jason Szumlanski]

We always specify a smaller neutral for Enphase IQ systems with 240V output
where the feeder neutral is only used for the Envoy data monitor. I have
never experienced a problem with an AHJ. However, this is not based on
Article 705. It's based on 220.61.

I just note why the neutral is downsized on the plans with the code
reference. Technically it can go all the way down to #14 neutral to
supply the 15A circuit for the Envoy data monitor, but we typically use #10
or the EGC size, whichever is larger.

The circuit from a breaker in the main panel to an AC combiner load center
is a feeder, so 220.61 applies. It also applies in the case of a
supply-side connection from the fusible disconnect and then continuing on
to an AC combining load center. If you are talking about a branch circuit
to an inverter, that isn't a feeder, so that's probably going to be a
different story. 705.95 could apply depending on what the neutral is needed
for. If it's strictly for voltage sensing or data comm, that might work.

Of course, if the PV AC Combiner has other loads, the feeder neutral needs
to be sized to handle these loads as well. This can be the case where we
are not using the Enphase IQ Combiner, but it's rare for us since we
usually dedicate a load center for PV AC combining only and exclude all
other loads.

Jason Szumlanski
Florida Solar Design Group






On Thu, May 7, 2020 at 11:04 AM Al Frishman  wrote:

> Hey Wrenchers,
> Wondering what you all think about NEC Article 705.95 and if downsizing
> the Neutral is common practice.   If your JHA accepts it and the model
> inverter you are installing complies do you see any issues with downsizing
> the Neutral?  This section of code has been in place since 2011 and I must
> admit I have been slow to adopt it.
>
> 705.95 Ampacity of Neutral Conductor. The ampacity of the neutral
> conductors shall comply with either (A) or (B)
> (A) Neutral Conductor for Single Phase, 2-Wire In- verter Output. If a
> single-phase, 2-wire inverter output is connected to the neutral and one
> ungrounded conductor (only) of a 3-wire system or of a 3-phase, 4-wire,
> wye- connected system, the maximum load connected between the neutral and
> any one ungrounded conductor plus the inverter output rating shall not
> exceed the ampacity of the neutral conductor.
>
> (B) Neutral Conductor for Instrumentation, Voltage Detection or Phase
> Detection. A conductor used solely for instrumentation, voltage
> detection, or phase detection and connected to a single-phase or 3-phase
> utility-interactive inverter, shall be permitted to be sized at less than
> the ampacity of the other current-carrying conductors and shall be sized
> equal to or larger than the equipment grounding conductor.
>
> *Al Frishman*
> EvolvedSolar
> (917) 699-6641
>
> ___
> List sponsored by Redwood Alliance
>
> List Address: RE-wrenches@lists.re-wrenches.org
>
> Change listserver email address & settings:
> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
> 
>
> List-Archive:
> http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html
> 
>
> List rules & etiquette:
> www.re-wrenches.org/etiquette.htm
> 
>
> Check out or update participant bios:
> www.members.re-wrenches.org
> 
>
>
___
List sponsored by Redwood Alliance

List Address: RE-wrenches@lists.re-wrenches.org

Change listserver email address & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org

List-Archive: 
http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html

List rules & etiquette:
www.re-wrenches.org/etiquette.htm

Check out or update participant bios:
www.members.re-wrenches.org

Re: [RE-wrenches] Rapid Shutdown Compliance

[Lones Tuss]

Hello All
OutBack does offer a RSD solutions.
Please see the links below
http://www.outbackpower.com/products/safety-compliance/rapid-shutdown-kits
We also pair up with the FireRaptor RSD product
http://www.outbackpower.com/products/safety-compliance/fireraptor-rapid-shutdown

In addition the FM100 has onboard AFCI
http://www.outbackpower.com/products/charge-controllers/flexmax-100-afci

I hope this helps.
Take Care All




From: RE-wrenches  On Behalf Of 
Jerry Shafer
Sent: Wednesday, April 29, 2020 11:34 PM
To: RE-wrenches 
Subject: Re: [RE-wrenches] Rapid Shutdown Compliance

Wrenches
We are taking two very different issues and mixing them together. RSD and 
Arc-fault are different, arc fault will and does prevent fires, RSD was brought 
out of the need to vent a roof that even with the meter pulled have 500 volts 
and resulted shocks to fire fighters by cutting into roofs or nearby conduite. 
This is fact not conjecture.
Arc fault is a fire preventer but requires nothing on the roof when using 
string level inverters. Now both RSD and arc-fault in off grid increase the 
complexity but the new charge controllers fit the arc and Tigo fixes the RSD 
issues.
I know everyone of you learned to use a smart phone and can now adapt again to 
this new tech, we have to be leaders in this industry and not well you know.
Jerry
NABCEP PV Inspector.
Been in this industry since 1978

On Wed, Apr 29, 2020, 6:57 PM Jay 
mailto:jay.pe...@gmail.com>> wrote:
Hi Drake

I will disagree, there have been many roof top fires.

But regardless we have to do these new regulations and I for one welcome the 
safety.

The main issue is accessing the faulty/suspect component under the module 
possibly requiring removing multiple modules, a slow and expensive process.

My technique is to install the MLPE at the edges of the array, using wire 
extensions. That way at most I have to remove a single module.  And Im working 
on a drop bracket which would allow better cooling and easier access without 
module removal to the MLPE, greatly reducing time to swap.

Jay

Peltz Power.






On Apr 29, 2020, at 7:59 AM, 
drake.chamber...@redwoodalliance.org
 wrote:


Clearly, rapid shutdown increases cost and reduces reliability. Given the 
excellent safety record of PV, prior to rapid shutdown being required, it is 
unnecessary. The few anecdotal incidents of PV fires were not enough to justify 
the requirement, especially on smaller systems.

According to a friend who worked for a local installation company that went 
under, a big part of the reason for their failure was the chronic replacement 
of microinverters and optimizers.

What steps can be taken to create some balance in the rapid shutdown 
requirements that are in the NEC?


---




On 2020-04-29 07:27, Sky Sims wrote:
So far rapid shutdown has been a nightmare. It's added a lot of cost for no 
measurable benefit.
Using always off devices like midnight solar and Tigo makes it impossible to 
test open circuit voltages. Which opens the door to tons of problems when 
commissioning systems.
Also we've been trying out midnight Solar's product and have had an absurd 
failure rate. Which means lots of truck rolls and troubleshooting and system 
downtime. They send replacement product but they aren't paying for the lost 
weeks of productivity.
We have Tigo product in hand and are deciding which project to try it on. But 
our big concern about using it is not only the inability to confirm open 
circuit voltage of the strings but also the way panels bypass if the device 
doesn't allow the panel to connect properly. Both of these features are a 
recipe for problems and potential troubleshooting nightmares. The warranty from 
Tigo doesn't cover our expense if the product fails. And that's really what our 
reservations about the product boil down to right now. If we're on a job with 
50 units and one fails, the contractor or the homeowner will be the ones eating 
the expense of finding it and replacing it. There has to be a better option.

Sky Sims
Https://EcologicalSystems.biz


On Apr 28, 2020, at 7:46 PM, Corey Shalanski 
mailto:coreso...@gmail.com>> wrote:
Now that 690.12 of the NEC 2017 has been in effect for several years, I am 
curious how designers and installers are meeting the associated requirements 
with string inverter-based systems (*not* considering microinverters or DC 
optimizers). I am generally a fan of the KISS principle, and as best I can 
determine the Tigo TS4-F device is one of the simplest options currently 
available on the market. What are others finding?

I'd love to hear about favored options for complying with rapid shutdown. Any 
success stories? or better yet, any early failures?

--
Corey Shalanski
Jah Light Solar
Portland, Jamaica
___
List sponsored by Redwood Alliance

List Address: 
RE-wrenches@lists.re-wrenches.org

Change listserver

Re: [RE-wrenches] Rapid Shutdown Compliance

[Brian Mehalic]

I agree: utilize the formal process, ideally with a group of folks.  If you
are a SEIA member, get involved in their Codes and Standards process.  The
additional directory language you suggest is not likely to be valuable to
many first responders without significant training and documentation, and
even then is still likely to get "lost" amongst other labels and
directories. RS as required now instead focuses on an initiation device(s),
so that the device is all responders need to look for - it's up to the
installer to specify and put in the correct gear to make RS happen, and the
AHJ to verify this.

Brian Mehalic
NABCEP Certified Solar PV Installation Professional™ R031508-59
National Electrical Code® CMP-4 Member
(520) 204-6639

Solar Energy International
http://www.solarenergy.org

SEI Professional Services
http://www.seisolarpros.com



On Thu, May 7, 2020 at 6:43 AM Christopher Warfel <
cwar...@entech-engineering.com> wrote:

> I believe Rapid Shutdown was mostly a solution looking for a problem.
> The only way I see this becoming "reasonable" is to present "grievances" to
> the Code Making Panel WITH a solution for their consideration.  Based on
> experience from being part of an outreach program that taught approximately
> 10k firefighters over four years, I have asked that they add to the
> Directory, the language that states what type of solar electric system is
> on site (Microinverter, dc optimizer, string, multimode, grid isolated) so
> that First Responders don't have to guess.  I realize this is different
> than MLPE, but it targets the person who Rapid Shutdown came into being
> for, and that was the First Responder.   Chris
>
>
> On 5/6/2020 10:37 PM, Ray wrote:
>
> Spending more time on the roof, while putting more equipment and parts to
> meet MLPE, means more trips up the ladder, which increases, not decreases
> the #1 worker safety danger: Falls.  Please correct me if I have somehow
> misunderstood this, but MLPE is not making installers safer based on OSHA
> information provided.   Also after installation, which system is more
> likely to require workers to return to work on the roof, pulling up
> modules, trying to find problem equipment?  More connections is More safe?
> Really?  I haven't had to climb back up on the roof on any of my older,
> lower voltage off grid work in almost a decade.
>
> Once again, MLPE has its place, (larger systems, multiple subarrays,
> higher voltage) but we should have sensible exemptions as have been
> mentioned already.  We are endangering ourselves and our employees
> needlessly, to comply with 690.12.
>
> Ray Walters
> Remote Solar
> 303 505-8760
>
> On 5/6/20 8:41 PM, drake.chamber...@redwoodalliance.org wrote:
>
> Interestingly enough, the data on the link
> 
>  provided
> shows accidents from gas explosions, falls, health problems and  industrial
> injuries. None of these incidents could have been prevented by module level
> power electronics. This is typical of the data that I've seen so far.
> ---
>
>
>
> On 2020-05-06 17:22, Martin Herzfeld wrote:
>
> There could be an issue of encouraging MLPE for worker safety?
>
> 1.  This is data involving incidents with workers in the OSHA Fatalities
> and Catastrophe Investigation Summaries found here:
>
> https://www.osha.gov/pls/imis/AccidentSearch.search?p_logger=1&acc_description=&acc_Abstract=solar&acc_keyword=&sic=&naics=&Office=All&officetype=All&endmonth=05&endday=05&endyear=2002&startmonth=05&startday=05&startyear=2021&InspNr=
>
> 2.  In the past I've observed an arc fault at the module level with
> traditional string systems without a listed arc-fault circuit interrupter
> NEC/CEC 690.11. The function in NEC/CEC 690.12 would be - to *reduce the
> shock hazard *- for *emergency responders* or *firefighters? (NEC 2020).*
> However, I've observed thermal events in the panelboard with plans and
> workmanship issues.
>
> On the other hand, falls are the #1 reason for incidents in the
> construction industry.
>
> All the best,
>
> Martin Herzfeld, Interstate Renewable Energy Council (IREC) Certified
> Master Trainer ™ for Photovoltaics (PV) Installation Professional #IREC
> 10037
> Contract Training Provider (CTP)
> Adjunct Professor, Energy
>
> California Solar & Electrical Contractor License  #00833782  C46, C10,
> D56, D31, C-7 - Since 2004
> Solar, Electrical, Trenching, Pole Installation & Maintenance,
> Instrumentation
>
> Contract Solar (PV) Technical Inspector - 3rd Party Inspections
> Underwriters Laboratories (UL) Certified PV Installer #17, OSHA 30
> OSHA-Authorized Construction Trainer #32-0105338
> CompTIA Certified Technical Classroom Trainer (CTT+) #T3NSZCNBBKB4QTQG
>
> * Professional Member, International Association of Electrical Inspectors
> #7035507 - 

Re: [RE-wrenches] Rapid Shutdown Compliance

[Christopher Warfel]

To change this, we need to recognize we are "fighting City Hall", and I 
doubt the CMP will be motivated to make changes on their own.  Maybe 
this has always been more political than technical, but it seems that 
those who are opposed to the current requirements need to make it known 
through the formal processes. The CMP is required to respond and in that 
response we can learn of their reasons for not accepting any changes, or 
the changes they would be willing to consider.  I just don't see things 
changing otherwise.


On 5/7/2020 10:18 AM, James Jarvis wrote:
If first responders are the point of all the rapid shutdown, there 
needs to be better exemptions. I personally have a 20kW solar array on 
a 100 year old unused barn at my farm. The roof is at 50 degrees slope 
and needs a 60ft boom lift to access. There was significant extra 
expense and effort for the rapid shut down. And there is absolutely 
zero chance that a first responder would do anything other than watch 
the barn burn. And now I have an array that needs a $1,000 piece of 
rental equipment to get to the back of any module.


There is a big difference between the stuff that is in big cities and 
what is in rural and what is in remote locations. For my telecom 
customers in Alaska and Antarctica, what is the point of decreasing 
reliability by putting module level electronics on solar arrays that 
require a multiple hour helicopter flight to get to. That's not 
protecting anybody other than the MLPE manufacturer's profit.



-James Jarvis
APRS World, LLC
+1-507-454-2727
http://www.aprsworld.com/


On Thu, May 7, 2020 at 8:43 AM Christopher Warfel 
> wrote:


I believe Rapid Shutdown was mostly a solution looking for a
problem.   The only way I see this becoming "reasonable" is to
present "grievances" to the Code Making Panel WITH a solution for
their consideration.  Based on experience from being part of an
outreach program that taught approximately 10k firefighters over
four years, I have asked that they add to the Directory, the
language that states what type of solar electric system is on site
(Microinverter, dc optimizer, string, multimode, grid isolated) so
that First Responders don't have to guess.  I realize this is
different than MLPE, but it targets the person who Rapid Shutdown
came into being for, and that was the First Responder.   Chris


On 5/6/2020 10:37 PM, Ray wrote:


Spending more time on the roof, while putting more equipment and
parts to meet MLPE, means more trips up the ladder, which
increases, not decreases the #1 worker safety danger: Falls. 
Please correct me if I have somehow misunderstood this, but MLPE
is not making installers safer based on OSHA information
provided. Also after installation, which system is more likely to
require workers to return to work on the roof, pulling up
modules, trying to find problem equipment?  More connections is
More safe?  Really?  I haven't had to climb back up on the roof
on any of my older, lower voltage off grid work in almost a decade.

Once again, MLPE has its place, (larger systems, multiple
subarrays, higher voltage) but we should have sensible exemptions
as have been mentioned already.  We are endangering ourselves and
our employees needlessly, to comply with 690.12.

Ray Walters
Remote Solar
303 505-8760
On 5/6/20 8:41 PM, drake.chamber...@redwoodalliance.org
 wrote:


Interestingly enough, the data on the link


 provided
shows accidents from gas explosions, falls, health problems and 
industrial injuries. None of these incidents could have been
prevented by module level power electronics. This is typical of
the data that I've seen so far.

---


On 2020-05-06 17:22, Martin Herzfeld wrote:


There could be an issue of encouraging MLPE for worker safety?
1.  This is data involving incidents with workers in the OSHA
Fatalities and Catastrophe Investigation Summaries found here:

https://www.osha.gov/pls/imis/AccidentSearch.search?p_logger=1&acc_description=&acc_Abstract=solar&acc_keyword=&sic=&naics=&Office=All&officetype=All&endmonth=05&endday=05&endyear=2002&startmonth=05&startday=05&startyear=2021&InspNr=
2.  In the past I've observed an arc fault at the module level
with traditional string systems without a listed arc-fault
circuit interrupter NEC/CEC 690.11. The function in NEC/CEC
690.12 would be - to _reduce the shock hazard _- for /emergency
responders/ or /firefighters? (NEC 2020)./  However, I've
observed thermal events in the panelboard with plans and
 

[RE-wrenches] Fwd: Neutral Sizing 705.95

[Al Frishman]

Hey Wrenchers,
Wondering what you all think about NEC Article 705.95 and if downsizing the 
Neutral is common practice.   If your JHA accepts it and the model inverter you 
are installing complies do you see any issues with downsizing the Neutral?  
This section of code has been in place since 2011 and I must admit I have been 
slow to adopt it.

705.95 Ampacity of Neutral Conductor. The ampacity of the neutral conductors 
shall comply with either (A) or (B)
(A) Neutral Conductor for Single Phase, 2-Wire In- verter Output. If a 
single-phase, 2-wire inverter output is connected to the neutral and one 
ungrounded conductor (only) of a 3-wire system or of a 3-phase, 4-wire, wye- 
connected system, the maximum load connected between the neutral and any one 
ungrounded conductor plus the inverter output rating shall not exceed the 
ampacity of the neutral conductor.

(B) Neutral Conductor for Instrumentation, Voltage Detection or Phase 
Detection. A conductor used solely for instrumentation, voltage detection, or 
phase detection and connected to a single-phase or 3-phase utility-interactive 
inverter, shall be permitted to be sized at less than the ampacity of the other 
current-carrying conductors and shall be sized equal to or larger than the 
equipment grounding conductor. 

Al Frishman
EvolvedSolar
(917) 699-6641

___
List sponsored by Redwood Alliance

List Address: RE-wrenches@lists.re-wrenches.org

Change listserver email address & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org

List-Archive: 
http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html

List rules & etiquette:
www.re-wrenches.org/etiquette.htm

Check out or update participant bios:
www.members.re-wrenches.org

Re: [RE-wrenches] Rapid Shutdown Compliance

[James Jarvis]

If first responders are the point of all the rapid shutdown, there needs to
be better exemptions. I personally have a 20kW solar array on a 100 year
old unused barn at my farm. The roof is at 50 degrees slope and needs a
60ft boom lift to access. There was significant extra expense and effort
for the rapid shut down. And there is absolutely zero chance that a first
responder would do anything other than watch the barn burn. And now I have
an array that needs a $1,000 piece of rental equipment to get to the back
of any module.

There is a big difference between the stuff that is in big cities and what
is in rural and what is in remote locations. For my telecom customers in
Alaska and Antarctica, what is the point of decreasing reliability by
putting module level electronics on solar arrays that require a multiple
hour helicopter flight to get to. That's not protecting anybody other than
the MLPE manufacturer's profit.


-James Jarvis
APRS World, LLC
+1-507-454-2727
http://www.aprsworld.com/


On Thu, May 7, 2020 at 8:43 AM Christopher Warfel <
cwar...@entech-engineering.com> wrote:

> I believe Rapid Shutdown was mostly a solution looking for a problem.
> The only way I see this becoming "reasonable" is to present "grievances" to
> the Code Making Panel WITH a solution for their consideration.  Based on
> experience from being part of an outreach program that taught approximately
> 10k firefighters over four years, I have asked that they add to the
> Directory, the language that states what type of solar electric system is
> on site (Microinverter, dc optimizer, string, multimode, grid isolated) so
> that First Responders don't have to guess.  I realize this is different
> than MLPE, but it targets the person who Rapid Shutdown came into being
> for, and that was the First Responder.   Chris
>
>
> On 5/6/2020 10:37 PM, Ray wrote:
>
> Spending more time on the roof, while putting more equipment and parts to
> meet MLPE, means more trips up the ladder, which increases, not decreases
> the #1 worker safety danger: Falls.  Please correct me if I have somehow
> misunderstood this, but MLPE is not making installers safer based on OSHA
> information provided.   Also after installation, which system is more
> likely to require workers to return to work on the roof, pulling up
> modules, trying to find problem equipment?  More connections is More safe?
> Really?  I haven't had to climb back up on the roof on any of my older,
> lower voltage off grid work in almost a decade.
>
> Once again, MLPE has its place, (larger systems, multiple subarrays,
> higher voltage) but we should have sensible exemptions as have been
> mentioned already.  We are endangering ourselves and our employees
> needlessly, to comply with 690.12.
>
> Ray Walters
> Remote Solar
> 303 505-8760
>
> On 5/6/20 8:41 PM, drake.chamber...@redwoodalliance.org wrote:
>
> Interestingly enough, the data on the link
> 
>  provided
> shows accidents from gas explosions, falls, health problems and  industrial
> injuries. None of these incidents could have been prevented by module level
> power electronics. This is typical of the data that I've seen so far.
> ---
>
>
>
> On 2020-05-06 17:22, Martin Herzfeld wrote:
>
> There could be an issue of encouraging MLPE for worker safety?
>
> 1.  This is data involving incidents with workers in the OSHA Fatalities
> and Catastrophe Investigation Summaries found here:
>
> https://www.osha.gov/pls/imis/AccidentSearch.search?p_logger=1&acc_description=&acc_Abstract=solar&acc_keyword=&sic=&naics=&Office=All&officetype=All&endmonth=05&endday=05&endyear=2002&startmonth=05&startday=05&startyear=2021&InspNr=
>
> 2.  In the past I've observed an arc fault at the module level with
> traditional string systems without a listed arc-fault circuit interrupter
> NEC/CEC 690.11. The function in NEC/CEC 690.12 would be - to *reduce the
> shock hazard *- for *emergency responders* or *firefighters? (NEC 2020).*
> However, I've observed thermal events in the panelboard with plans and
> workmanship issues.
>
> On the other hand, falls are the #1 reason for incidents in the
> construction industry.
>
> All the best,
>
> Martin Herzfeld, Interstate Renewable Energy Council (IREC) Certified
> Master Trainer ™ for Photovoltaics (PV) Installation Professional #IREC
> 10037
> Contract Training Provider (CTP)
> Adjunct Professor, Energy
>
> California Solar & Electrical Contractor License  #00833782  C46, C10,
> D56, D31, C-7 - Since 2004
> Solar, Electrical, Trenching, Pole Installation & Maintenance,
> Instrumentation
>
> Contract Solar (PV) Technical Inspector - 3rd Party Inspections
> Underwriters Laboratories (UL) Certified PV Installer #17, OSHA 30
> OSHA-Authorized Construction Trainer #32-0105338
> CompTIA 

Re: [RE-wrenches] Skybox

[Dave Angelini Offgrid Solar]

The 2 Skybox inverters I installed both were based on soft start water
pumps (grundfos) and a soft start air compressor for the garage. It cost
more to replace the electric dryer and water heater than the solar. The
owners then had a home that could run off Skybox or a small genset. These
were both for Cal Fire guy's. They knew what they did not want from
experience. I just helped them get there. 

Dave Angelini Offgrid Solar
"we
go where powerlines don't"
http://members.sti.net/offgridsolar/ [1]
e-mail
offgridso...@sti.net [2]
text 209 813 0060

On Wed, 6 May 2020 18:35:44
-0700, Jay  wrote:  5 kva max, no surge regardless of use.A rather
large shortcoming for a battery inverter.I'm guessing they were
thinking more of battery sell mode vs powering loads directly, but just a
guess.Jay   Peltz power  
 On May 6, 2020, at 6:31 PM, Dave Tedeyan
wrote:

Is the 5kw limit and no surge capacity for the backed up AC
loads only when operating off grid? If you occasionally trip a breaker
during the relatively rare times when the grid is out (around here at
least) it is not such a big deal. But if you had to deal with that daily,
you would have to be way more conservative as to what loads are allowed to
be backed up.   Also, is there an inverter bypass built into the BOS
enclosure, or do you need to wire up a separate one in case of inverter
failure.   Cheers,  Dave
  DAVE TEDEYAN, PE Senior Engineer
| Taitem Engineering, PC 
 110 South Albany Street | Ithaca, NY 14850 o.
607.277.1118 x121 f. 607.277.2119 www.taitem.com [3]   Solar *
Sustainability * Energy * Design Certified B-Corporation since 2013

  On
Mon, May 4, 2020 at 8:24 PM  wrote:   I'm finding the SkyBox to be reliable
hardware, if you don't need big surge capability. But the software is still
in flux. I have had to reject software updates that froze the system, going
back to the previous version to bring it back again.   One issue is that AC
coupling does not work with multiple Skyboxen, unlike with older Radians.
Another huge problem that seems to be software related is that dual
SkyBoxen with different sized solar arrays discharge their battery banks at
different rates. This becomes an issue in multiple day grid outages like we
now expect in north CA fire season. You'd think the SkyBox master-slave
relationship would allow them to coordinate, but this causes the one with a
smaller solar array to run down it's battery sooner, faulting the system
causing a complete shutdown of both SkyBoxen.  OutBack says they are not
fixing this, so I'm looking at SolArk for systems larger than 5 kW.   Don
Barch Energy Solar   Original Message 
 Subject:
RE-wrenches Digest, Vol 13, Issue 124
 From:
re-wrenches-requ...@lists.re-wrenches.org [5]
 Date: Mon, May 04, 2020 2:40
pm
 To: re-wrenches@lists.re-wrenches.org [6]

 Send RE-wrenches mailing
list submissions to
 re-wrenches@lists.re-wrenches.org [7]

 To subscribe
or unsubscribe via the World Wide Web, visit

http://lists.re-wrenches.org/listinfo.cgi/re-wrenches-re-wrenches.org [8]

or, via email, send a message with subject or body 'help' to

re-wrenches-requ...@lists.re-wrenches.org [9]

 You can reach the person
managing the list at
 re-wrenches-ow...@lists.re-wrenches.org [10]

 When
replying, please edit your Subject line so it is more specific
 than "Re:
Contents of RE-wrenches digest..."

 When responding to posts within the
Digest, be sure to restore the Subject: line to the original, and please
edit out any extraneous lines from the quoted message.

 Today's Topics:


1. Skybox (Dave Tedeyan)
 2. Re: Skybox (Jerry Shafer)
 3. Re: Skybox
(jay)
 4. Re: Skybox (penobscotso...@midmaine.com [11])


--


Message: 1
 Date: Sun, 3 May 2020 21:32:38 -0400
 From: Dave Tedeyan 
 To:
RE-wrenches 
 Subject: [RE-wrenches] Skybox
 Message-ID:

 Content-Type:
text/plain; charset="utf-8"

 Hi All,

 Does anyone have experience using
Outback's Skybox inverter? I have someone
 interested and am curious to
hear if people have had luck with them and if
 they are reliable.

 Also,
I've been seeing promo material for Fronius' Gen 24 Plus inverter,
 which
looks like it fills the same niche. Are those even available for
 purchase
yet? If so, does anyone have experience with these?

 Cheers,
 Dave

 *Dave
Tedeyan, PE*
 Senior Engineer | Taitem Engineering, PC

 110 South Albany
Street | Ithaca, NY 14850
 o. *607.277.1118 x121* f. 607.277.2119

www.taitem.com [15]

 Solar ? Sustainability ? Energy ? Design
 Certified
B-Corporation since 2013
 -- next part --
 An HTML
attachment was scrubbed...
 URL:  someone interested and am curious to hear
if people have had luck with them
 > and if they are reliable.
 >
 > Also,
I've been seeing promo material for Fronius' Gen 24 Plus inverter,
 > which
looks like it fills the same niche. Are those even available for
 >
purchase yet? If so, does anyon

Re: [RE-wrenches] Rapid Shutdown Compliance

[Christopher Warfel]

I believe Rapid Shutdown was mostly a solution looking for a problem.   
The only way I see this becoming "reasonable" is to present "grievances" 
to the Code Making Panel WITH a solution for their consideration.  Based 
on experience from being part of an outreach program that taught 
approximately 10k firefighters over four years, I have asked that they 
add to the Directory, the language that states what type of solar 
electric system is on site (Microinverter, dc optimizer, string, 
multimode, grid isolated) so that First Responders don't have to guess.  
I realize this is different than MLPE, but it targets the person who 
Rapid Shutdown came into being for, and that was the First Responder.   
Chris



On 5/6/2020 10:37 PM, Ray wrote:


Spending more time on the roof, while putting more equipment and parts 
to meet MLPE, means more trips up the ladder, which increases, not 
decreases the #1 worker safety danger: Falls. Please correct me if I 
have somehow misunderstood this, but MLPE is not making installers 
safer based on OSHA information provided.   Also after installation, 
which system is more likely to require workers to return to work on 
the roof, pulling up modules, trying to find problem equipment?  More 
connections is More safe?  Really?  I haven't had to climb back up on 
the roof on any of my older, lower voltage off grid work in almost a 
decade.


Once again, MLPE has its place, (larger systems, multiple subarrays, 
higher voltage) but we should have sensible exemptions as have been 
mentioned already.  We are endangering ourselves and our employees 
needlessly, to comply with 690.12.


Ray Walters
Remote Solar
303 505-8760
On 5/6/20 8:41 PM, drake.chamber...@redwoodalliance.org wrote:


Interestingly enough, the data on the link 
 provided 
shows accidents from gas explosions, falls, health problems and  
industrial injuries. None of these incidents could have been 
prevented by module level power electronics. This is typical of the 
data that I've seen so far.


---


On 2020-05-06 17:22, Martin Herzfeld wrote:


There could be an issue of encouraging MLPE for worker safety?
1.  This is data involving incidents with workers in the OSHA 
Fatalities and Catastrophe Investigation Summaries found here:

https://www.osha.gov/pls/imis/AccidentSearch.search?p_logger=1&acc_description=&acc_Abstract=solar&acc_keyword=&sic=&naics=&Office=All&officetype=All&endmonth=05&endday=05&endyear=2002&startmonth=05&startday=05&startyear=2021&InspNr=
2.  In the past I've observed an arc fault at the module level with 
traditional string systems without a listed arc-fault circuit 
interrupter NEC/CEC 690.11. The function in NEC/CEC 690.12 would be 
- to _reduce the shock hazard _- for /emergency responders/ or 
/firefighters? (NEC 2020)./ However, I've observed thermal events in 
the panelboard with plans and workmanship issues.
On the other hand, falls are the #1 reason for incidents in the 
construction industry.

All the best,

Martin Herzfeld, Interstate Renewable Energy Council (IREC) 
Certified Master Trainer ™ for Photovoltaics (PV) Installation 
Professional #IREC 10037

Contract Training Provider (CTP)
Adjunct Professor, Energy

California Solar & Electrical Contractor License  #00833782  C46, 
C10, D56, D31, C-7 - Since 2004
Solar, Electrical, Trenching, Pole Installation & Maintenance, 
Instrumentation


Contract Solar (PV) Technical Inspector - 3rd Party Inspections
Underwriters Laboratories (UL) Certified PV Installer #17, OSHA 30
OSHA-Authorized Construction Trainer #32-0105338
CompTIA Certified Technical Classroom Trainer (CTT+) #T3NSZCNBBKB4QTQG

* Professional Member, International Association of Electrical 
Inspectors  #7035507 - Since 2006
* Accredited and Registered North American Board of Certified Energy 
Practitioners (NABCEP) Continuing Education (CE) Training Provider


On Thu, Apr 30, 2020, 8:29 AM > wrote:



I would like to see real data on the fire risk of string
inverters. Anecdotal problems are not data.
The industry is definitely heading toward MLPE due to the rapid
shutdown requirements. In many cases MLPE makes sense, in other
cases it doesn't.
Systems that are more cost effective and reliable can often be
built by using string inverters.
---


On 2020-04-29 22:05, Jason Szumlanski wrote:

"Rapid Shutdown does not prevent fires."

Not true. If the effect of RS is to steer the market to
MLPE, I believe it has a significant impact on reducing fire
risk. As one who has watched a DC conductor fire smolder out
of control, I am sold on an AC module or microinverter
architecture. While RS on a DC array doesn't necessarily