Re: [RE-wrenches] Utility refuses to upgrade transformer to accommodate photovoltaic system

[jay peltz]

Hi Jason

Out of curiosity how big is this PV system?

Good luck and keep us informed. 

Jay 

Peltz power




> On Jan 16, 2014, at 12:45 PM, "b...@midnitesolar.com"  
> wrote:
> 
> 
> I wonder if anybody at the FSEC might have some good advice here ?
> Just a wild guess...
> boB
> 
>> On 1/16/2014 12:08 PM, Jason Szumlanski wrote:
>> Florida Power and Light (FPL) rejected my request to upgrade a utility 
>> transformer (at my cost) to accommodate backfeed from a PV system. Their 
>> basis is their own "Net Metering Guidelines," which are not the same as the 
>> Florida Public Service Commission's Netmetering Rule (law). I believe the 
>> property owner is within his rights to proceed with the project and should 
>> be approved for interconnection. I'm appealing to the PSC for assistance, 
>> but if you have any advice or contacts that may be able to help, please 
>> contact me off list.
>> 
>> What is boils down to (I think) is the utility's interpretation of the Rule. 
>> They believe the intent is to allow people to netmeter to the extent that it 
>> offsets their consumption only. If that were strictly the case, there would 
>> be no provision for payment for excess energy produced annually (at 
>> wholesale rates). The Netmetering Rule allows backfeed up to 90% of the 
>> customer's service capacity, without regard for the energy consumption, but 
>> doesn't clarify if the utility is obligated to upgrade service capacity upon 
>> request.
>> 
>> They've dug their heels in, and now it's David vs. Goliath. (David did win 
>> that one, right?)
>> 
>> 
>> Jason Szumlanski
>> Fafco Solar
> 
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Re: [RE-wrenches] Concrete tight versus raintight

[Erika Weliczko]

Madison Electric has an actual rubber washer to seal fitting to box as lock 
ring is tightened.  

They are however fussy with the internal rings. 

Erika Weliczko
REpower Solutions
cell: 216.402.4458

On Jan 16, 2014, at 2:54 PM, "William Miller"  wrote:

> Friends:
>  
> We used some Bridgeport fittings yesterday.  My foreman reports the following:
>  
> The new blue rain tite connectors have a prob. The connectors have a plastic 
> gasket/ring that seals between the connector body and the box. It is 
> impossible to tighten the con to box without destroying the ring or having a 
> slightly loose con/box connection. A loose connection means poor bonding.
>  
> I would add that any looseness of these fittings can contribute to mechanical 
> failure of conduit runs.  We rely on code compliant strapping *and* secure 
> tightening of fittings to keep a conduit assembly secure and in place for 
> years to come.  It looks like we need to find a fitting with firmer washers.  
> The Arlington NMLT fittings have yellow washers that are pretty rigid.  I 
> will rob one and try it on the Bridgeports.  We bought a quantity of the EMT 
> fittings and I don’t want to have to replace them…
>  
> William
>  
>  
>  
> From: re-wrenches-boun...@lists.re-wrenches.org 
> [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of August Goers
> Sent: Thursday, January 16, 2014 8:00 AM
> To: RE-wrenches
> Subject: Re: [RE-wrenches] Concrete tight versus raintight
>  
> Hi William,
>  
> About 5 years ago this became a big issue up in San Francisco and we had to 
> learn the hard way. We used to just go buy outdoor EMT fittings and we were 
> okay, then the inspectors started requiring fittings that say raintight or 
> wet location (often stamped “wetloc”) on them. I don’t know for certain, but 
> I believe it might have been a clarification added in the 2008 NEC at the 
> time. See “NEC 358.42 Couplings and Connectors. Couplings and connectors used 
> with EMT shall be made up tight. Where buried in masonry or concrete, they 
> shall be concretetight type. Where installed in wet locations, they shall 
> comply with 314.15.”
>  
> If you go over to NEC 314.15 they mention that fittings installed in wet 
> locations shall be listed for use in wet locations.
>  
> So, you just need to make sure that the fittings you get are listed for the 
> correct purpose. I have seen both concretetight and wetloc type. As someone 
> else mentioned, most of the wetloc fittings have a plastic sealing ring in 
> them and many or blue colored.
>  
> Best,
>  
> August
> Luminalt
>  
> From: re-wrenches-boun...@lists.re-wrenches.org 
> [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of William Miller
> Sent: Wednesday, January 15, 2014 10:32 PM
> To: RE-wrenches
> Subject: [RE-wrenches] Concrete tight versus raintight
>  
> Friends:
>  
> It appears I may have a whole in my education.  I thought all EMT compression 
> fittings were alike.  It appears that I have been using “concrete tight” 
> fittings where I should have been using “raintight” fittings.  Did they use 
> to be the same item?  I did a web search on the differences and came up 
> empty.  I want to be informed in this area and appreciate any knowledge.
>  
> William Miller
>  
>  
> 
> Lic 773985
> millersolar.com
> 805-438-5600
>  
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 2013.0.3462 / Virus Database: 3681/7008 - Release Date: 01/16/14
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Re: [RE-wrenches] Concrete tight versus raintight

[August Goers]

Hi William,



This has also been a longstanding problem for us – and one that we don’t
have a good solution for. Technically speaking we’re supposed to use the
listed fitting with all the parts that come with it. However, the rubber
gaskets between the connector and box cause issues with tightening as you
mention below and also crack over time. Some inspectors don’t want us using
the gaskets at all. I like your idea about using the Arlington
yellow-colored gaskets. They are nice a solid. We’ve been putting a good
quality clear sealant around all of our outdoor fittings for a while now
and it seems to have stopped most of the water intrusion into the conduit.
We also drill drip holes in boxes where we feel there is a good chance that
moisture will enter. This is also a contentious decision as technically the
listed outdoor box shouldn’t have holes drilled in it…



Best, August



*From:* re-wrenches-boun...@lists.re-wrenches.org [mailto:
re-wrenches-boun...@lists.re-wrenches.org] *On Behalf Of *William Miller
*Sent:* Thursday, January 16, 2014 11:54 AM
*To:* 'RE-wrenches'
*Subject:* Re: [RE-wrenches] Concrete tight versus raintight



Friends:



We used some Bridgeport fittings yesterday.  My foreman reports the
following:



*The new blue rain tite connectors have a prob. The connectors have a
plastic gasket/ring that seals between the connector body and the box. It
is impossible to tighten the con to box without destroying the ring or
having a slightly loose con/box connection. A loose connection means poor
bonding. *



I would add that any looseness of these fittings can contribute to
mechanical failure of conduit runs.  We rely on code compliant strapping *
*and** secure tightening of fittings to keep a conduit assembly secure and
in place for years to come.  It looks like we need to find a fitting with
firmer washers.  The Arlington NMLT fittings have yellow washers that are
pretty rigid.  I will rob one and try it on the Bridgeports.  We bought a
quantity of the EMT fittings and I don’t want to have to replace them…



William







*From:* re-wrenches-boun...@lists.re-wrenches.org [
mailto:re-wrenches-boun...@lists.re-wrenches.org]
*On Behalf Of *August Goers
*Sent:* Thursday, January 16, 2014 8:00 AM
*To:* RE-wrenches
*Subject:* Re: [RE-wrenches] Concrete tight versus raintight



Hi William,



About 5 years ago this became a big issue up in San Francisco and we had to
learn the hard way. We used to just go buy outdoor EMT fittings and we were
okay, then the inspectors started requiring fittings that say raintight or
wet location (often stamped “wetloc”) on them. I don’t know for certain,
but I believe it might have been a clarification added in the 2008 NEC at
the time. See “NEC 358.42 Couplings and Connectors. Couplings and
connectors used with EMT shall be made up tight. Where buried in masonry or
concrete, they shall be concretetight type. Where installed in wet
locations, they shall comply with 314.15.”



If you go over to NEC 314.15 they mention that fittings installed in wet
locations shall be listed for use in wet locations.



So, you just need to make sure that the fittings you get are listed for the
correct purpose. I have seen both concretetight and wetloc type. As someone
else mentioned, most of the wetloc fittings have a plastic sealing ring in
them and many or blue colored.



Best,



August

Luminalt



*From:* re-wrenches-boun...@lists.re-wrenches.org [mailto:
re-wrenches-boun...@lists.re-wrenches.org] *On Behalf Of *William Miller
*Sent:* Wednesday, January 15, 2014 10:32 PM
*To:* RE-wrenches
*Subject:* [RE-wrenches] Concrete tight versus raintight



Friends:



It appears I may have a whole in my education.  I thought all EMT
compression fittings were alike.  It appears that I have been using
“concrete tight” fittings where I should have been using “raintight”
fittings.  Did they use to be the same item?  I did a web search on the
differences and came up empty.  I want to be informed in this area and
appreciate any knowledge.



William Miller





[image: Gradient Cap]

Lic 773985

millersolar.com 

805-438-5600


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Re: [RE-wrenches] Utility refuses to upgrade transformer to accommodate photovoltaic system

[b...@midnitesolar.com]

I wonder if anybody at the FSEC might have some good advice here ?
Just a wild guess...
boB

On 1/16/2014 12:08 PM, Jason Szumlanski wrote:
Florida Power and Light (FPL) rejected my request to upgrade a utility 
transformer (at my cost) to accommodate backfeed from a PV system. 
Their basis is their own "Net Metering Guidelines," which are not the 
same as the Florida Public Service Commission's Netmetering Rule 
(law). I believe the property owner is within his rights to proceed 
with the project and should be approved for interconnection. I'm 
appealing to the PSC for assistance, but if you have any advice or 
contacts that may be able to help, please contact me off list.


What is boils down to (I think) is the utility's interpretation of the 
Rule. They believe the intent is to allow people to netmeter to the 
extent that it offsets their consumption only. If that were strictly 
the case, there would be no provision for payment for excess energy 
produced annually (at wholesale rates). The Netmetering Rule allows 
backfeed up to 90% of the customer's service capacity, without regard 
for the energy consumption, but doesn't clarify if the utility is 
obligated to upgrade service capacity upon request.


They've dug their heels in, and now it's David vs. Goliath. (David did 
win that one, right?)



Jason Szumlanski
Fafco Solar




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[RE-wrenches] Utility refuses to upgrade transformer to accommodate photovoltaic system

[Jason Szumlanski]

Florida Power and Light (FPL) rejected my request to upgrade a utility
transformer (at my cost) to accommodate backfeed from a PV system. Their
basis is their own "Net Metering Guidelines," which are not the same as the
Florida Public Service Commission's Netmetering Rule (law). I believe the
property owner is within his rights to proceed with the project and should
be approved for interconnection. I'm appealing to the PSC for assistance,
but if you have any advice or contacts that may be able to help, please
contact me off list.

What is boils down to (I think) is the utility's interpretation of the
Rule. They believe the intent is to allow people to netmeter to the extent
that it offsets their consumption only. If that were strictly the case,
there would be no provision for payment for excess energy produced annually
(at wholesale rates). The Netmetering Rule allows backfeed up to 90% of the
customer's service capacity, without regard for the energy consumption, but
doesn't clarify if the utility is obligated to upgrade service capacity
upon request.

They've dug their heels in, and now it's David vs. Goliath. (David did win
that one, right?)


Jason Szumlanski
Fafco Solar
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Re: [RE-wrenches] Concrete tight versus raintight

[William Miller]

Friends:

 

We used some Bridgeport fittings yesterday.  My foreman reports the
following:

 

The new blue rain tite connectors have a prob. The connectors have a plastic
gasket/ring that seals between the connector body and the box. It is
impossible to tighten the con to box without destroying the ring or having a
slightly loose con/box connection. A loose connection means poor bonding. 

 

I would add that any looseness of these fittings can contribute to
mechanical failure of conduit runs.  We rely on code compliant strapping
*and* secure tightening of fittings to keep a conduit assembly secure and in
place for years to come.  It looks like we need to find a fitting with
firmer washers.  The Arlington NMLT fittings have yellow washers that are
pretty rigid.  I will rob one and try it on the Bridgeports.  We bought a
quantity of the EMT fittings and I don't want to have to replace them.

 

William

 

 

 

From: re-wrenches-boun...@lists.re-wrenches.org
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of August Goers
Sent: Thursday, January 16, 2014 8:00 AM
To: RE-wrenches
Subject: Re: [RE-wrenches] Concrete tight versus raintight

 

Hi William,

 

About 5 years ago this became a big issue up in San Francisco and we had to
learn the hard way. We used to just go buy outdoor EMT fittings and we were
okay, then the inspectors started requiring fittings that say raintight or
wet location (often stamped "wetloc") on them. I don't know for certain, but
I believe it might have been a clarification added in the 2008 NEC at the
time. See "NEC 358.42 Couplings and Connectors. Couplings and connectors
used with EMT shall be made up tight. Where buried in masonry or concrete,
they shall be concretetight type. Where installed in wet locations, they
shall comply with 314.15."

 

If you go over to NEC 314.15 they mention that fittings installed in wet
locations shall be listed for use in wet locations. 

 

So, you just need to make sure that the fittings you get are listed for the
correct purpose. I have seen both concretetight and wetloc type. As someone
else mentioned, most of the wetloc fittings have a plastic sealing ring in
them and many or blue colored.

 

Best,

 

August

Luminalt

 

From: re-wrenches-boun...@lists.re-wrenches.org
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of William
Miller
Sent: Wednesday, January 15, 2014 10:32 PM
To: RE-wrenches
Subject: [RE-wrenches] Concrete tight versus raintight

 

Friends:

 

It appears I may have a whole in my education.  I thought all EMT
compression fittings were alike.  It appears that I have been using
"concrete tight" fittings where I should have been using "raintight"
fittings.  Did they use to be the same item?  I did a web search on the
differences and came up empty.  I want to be informed in this area and
appreciate any knowledge.

 

William Miller

 

 

Gradient Cap

Lic 773985

millersolar.com  

805-438-5600

 

  _  

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2013.0.3462 / Virus Database: 3681/7008 - Release Date: 01/16/14

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Re: [RE-wrenches] NEC 2014 690.12 Rapid Shutdown

[Bill Brooks]

Jeffrey,

 

Sounds like you need to get involved in the code making process since you
have so many good ideas on how to improve the language. I like
confrontational discussions as long as they lead to a better understanding
and constructive outcomes.

 

About 30 people worked on this language, so it is definitely not perfect.
However, I don't think it is quite as bad as you make it out to be. I wanted
to jump in since some of your conclusions were not correct.

 

This is a circuit requirement, not a disconnecting means requirement, since
it has to do with shock hazard of PV circuits in and around a building. This
is for firefighter safety. 30V is the international standard for touch safe
in a wet location. 240VA is to set a limit on the available power on a
circuit. Contactor combiners, which would be part of a compliant solution,
have 24V control circuits. The other reasoning for 240VA is that internally,
72-Cell PV modules can be divided into segments of this power level for the
foreseeable future (more on that another day).

 

If the conductors stay outside, you have 10' from the array to place your
shutdown device. On large central systems, this would likely be a contactor
combiner-most manufacturers sell these. If the conductors are going
immediately into the building, as with residential and integrated systems, a
shutdown device would have to be within 5' of entering the building. If goes
outside for a while, then inside the building, the total length could be no
more than 10' and no more than 5' inside the building-this is not additive.
Remember, all this is for firefighter safety.

 

As Brian Mehalic and others have pointed out, the language does not specify
where the shutdown initiating device is to be located. The lack of detail is
more for flexibility than it is to give an AHJ license to make an installer
do anything they want. 

 

With grid-tie only systems (no battery backup), it would be most convenient
and cost effective to have a system that initiates the shutdown on loss of
utility. In this way, a firefighter can do what they normally do, shut down
utility power to the building, and the rapid shutdown would automatically
initiate. This does not necessitate an additional disconnecting means for a
load-side PV connection. The main breaker could be the initiating device.
For a supply-side connection, the NEC already requires that the PV
disconnect switch be located adjacent to the service disconnecting means
(article 230).

 

The biggest issue with string inverters (central inverters) is that there is
a need to shutdown the capacitor input side of the inverter since that stays
energized for 5 minutes or more. The 10 seconds was to provide a means to
rapidly discharge the capacitors rather than requiring a relay or tripping
device. Doing something other than a relay will require a test laboratory to
evaluate the function-guess what?-we don't have a standard yet to evaluate
those products. Sounds like you might want to work on that committee.

 

It is more complicated for battery backup systems. Midnite Solar's birdhouse
products are the best I have seen so far to address this concern. Since dc
and ac circuits are not differentiated, battery backup systems need to have
a shutdown process that works independently of a utility outage for obvious
reasons, and it must shutdown both the dc circuits and the backup ac
circuits. A separate switch, like the birdhouse, would be necessary that
only controls these functions in an emergency situation.

 

Is the language not detailed-possibly. This was done to provide flexibility
rather than create problems. Fire departments have been requiring rooftop
disconnects for years in California. These disconnects are nearly worthless
from a shock prevention point of view since capacitors in the inverter stay
charged or there are multiple disconnecting means feeding each other. We
have been trying to hold the fire community off of rooftop disconnect
requirements so we could work on a solution that actually does what they
want it to do. There is a long discussion on this in the appendix of my
"Understanding the CalFire Guidelines" document on the SolarABCs website.

 

The 2014 NEC language was a compromise worked out with the solar industry
(yes string inverter companies as well) in response to the first version of
the proposal which was to require module-level shutdown. This is not
module-level shutdown, it is PV output circuit shutdown (combiner box
shutdown is another way to look at it). However, the 2017 NEC cycle is this
year and there was a lot of talk about requiring module-level shutdown this
time around. 

 

I hope this helps. I will be writing articles for IAEI journal and other
periodicals on this subject since it was a very far-reaching and potentially
confusing new requirement in the NEC. Thanks for your interest and let's
keep the constructive dialogue going on the subject. It is time to get
involved in the NEC update process again.

 

Bill 

Re: [RE-wrenches] Concrete tight versus raintight

[August Goers]

Hi William,



About 5 years ago this became a big issue up in San Francisco and we had to
learn the hard way. We used to just go buy outdoor EMT fittings and we were
okay, then the inspectors started requiring fittings that say raintight or
wet location (often stamped “wetloc”) on them. I don’t know for certain,
but I believe it might have been a clarification added in the 2008 NEC at
the time. See “NEC 358.42 Couplings and Connectors. Couplings and
connectors used with EMT shall be made up tight. Where buried in masonry or
concrete, they shall be concretetight type. Where installed in wet
locations, they shall comply with 314.15.”



If you go over to NEC 314.15 they mention that fittings installed in wet
locations shall be listed for use in wet locations.



So, you just need to make sure that the fittings you get are listed for the
correct purpose. I have seen both concretetight and wetloc type. As someone
else mentioned, most of the wetloc fittings have a plastic sealing ring in
them and many or blue colored.



Best,



August

Luminalt



*From:* re-wrenches-boun...@lists.re-wrenches.org [mailto:
re-wrenches-boun...@lists.re-wrenches.org] *On Behalf Of *William Miller
*Sent:* Wednesday, January 15, 2014 10:32 PM
*To:* RE-wrenches
*Subject:* [RE-wrenches] Concrete tight versus raintight



Friends:



It appears I may have a whole in my education.  I thought all EMT
compression fittings were alike.  It appears that I have been using
“concrete tight” fittings where I should have been using “raintight”
fittings.  Did they use to be the same item?  I did a web search on the
differences and came up empty.  I want to be informed in this area and
appreciate any knowledge.



William Miller





[image: Gradient Cap]

Lic 773985

millersolar.com 

805-438-5600
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Re: [RE-wrenches] Concrete tight versus raintight

[Jeffrey Quackenbush]

>You're right that there are two types of compression connectors. I think the 
>rain tight ones have an extra piece near the compression ring. At Home Depot, 
>I believe the rain tight ones are blue and they cost a little more. See the 
>Halex catalog:

http://www.halexco.com/products.cfm?siteSection=consumer&product_subgroup=cc&product_group=EMT


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Re: [RE-wrenches] NEC 2014 690.12 Rapid Shutdown

[Jeffrey Quackenbush]

Wrenches,

There is no guidance in the Code text for where the shutdown should take place. 
(1) says: "Requirements for controlled conductors shall apply only to PV system 
conductors of more than 1.5m (5') in length inside a building, or more than 3m 
(10') from a PV array."

So, the provisions apply if the circuit 10' from the array and 5' inside a 
building, but no mention is made of where the shutdown actually needs take 
place in the circuit. In the video Bill Brooks suggests that the shutdown 
mechanism should also be placed within this 10'/5' boundary but that is just an 
inference -- nowhere in the text is this actually specified. If that was the 
intent of the Code committee, then they've done a poor job actually expressing 
it in English.

I'm concerned that some AHJs will interpret this to exclude all central 
inverter systems (without the addition of cost-inducing secondary DC-DC 
converters like Tigo) because the combiner or junction box can be many feet 
from the actual beginning of a home run under the array. Alternately, 
permissive AHJs could allow this function to be fulfilled anywhere, meaning 
that the implementation won't meet the intent of the writers.

I'm also concerned, as Isaac mentioned, that there are no requirements for how 
the shutdown be initiated, or that it contains of the accessibility and 
grouping requirements that are always included for disconnects. I really think 
this should be treated and categorized as a disconnect requirement, not a 
circuit requirement, because that is the ultimate function that's intended. 

I'm surprised none of the inverter manufacturers have chosen to comment here, 
as this could dramatically impact the sales of central inverters.


Jeffrey Quackenbush___
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