[RE-wrenches] Rapid Shutdown

Tue Mar 15 15:43:29 PDT 2016

As a side note to this conversation, this brings up an advantage of the
Tesla Powerwall battery – my understanding is that it will turn off
immediately at the Powerwall battery when disconnected at the inverter.
This is another nice benefit of having DC-to-DC conversion smarts in the
Powerwall.

-August

Luminalt

*From:* RE-wrenches [mailto:re-wrenches-bounces at lists.re-wrenches.org] *On
Behalf Of *bob at midnitesolar.com
*Sent:* Tuesday, March 15, 2016 3:23 PM
*To:* RE-wrenches
*Subject:* Re: [RE-wrenches] Rapid Shutdown

MidNite's  Rapid Shutdown Sustems are UL listed.

 If you have any questions, please email Ryan at   ryan at midnitesolar.com.

Ryan  said we were actually having a webinar on this subject later this
week, too.

No solenoids so no night tare loss on the battery side or the  PV side.

*****    *****   *****

 In addition, Robin says...

Ray, although there is some risk of your neighbors kids shutting off your
refrigerator, we cannot control that.

MidNite does make very elegant solutions for your RSS issue.

We are UL listed and recently reduced the price of our Birdhouse system.
When it comes to battery based shut off systems, we are your solution.

Have you installed one of our Birdhouse systems? If not, contact us and we
will get you set up.

Thanks,
Robin Gudgel

-James Jefferson Jarvis  wrote....

>>>Larry,
>>>Any details on these $120 solenoids? Are they latching coil, or will we
be burning another 5 to 20 watts per device to keep them closed?
>>>I did a quick search of Midnite's site and got no relevant hits with
relay, solenoid, or contactor as search terms.
>>>Thanks,
>>>-James Jefferson Jarvis

I find that Google works much better for most web site searches.

boB

On 3/15/2016 2:16 PM, Ray Walters wrote:

So Pat, you stated "*There are simple ways to work around these issues*".
Actually, the major off grid inverter manus do not have a solution for this
( Magnum, Outback, Exeltech, Schneider, SMA)
Can you show us an example of a UL listed system that has multiple
inverters (over 8 kW cont.), with rapid disconnects within 5 ft?  I'm
really looking for actual solutions here folks, and I haven't seen a single
system ever built, much less even a simple wiring diagram that would comply
with this new requirement. (*690.12(5) Equipment that performs the rapid
shutdown shall be listed and identified*)

Also, for every improvement comes a whole new set of problems.  Your "*What
would I do in my own house?*" is an excellent point.  Personally, I would
not want the neighbor's kids to be able to shut off my refrigerator or
grandma's breathing machine with the touch of an outside accessible,
unlockable button.

I've been cobbling together code compliant systems for 2 decades, so yes,
I'm sure I could scavenge relays from the EV world to do this.  But the
days of inventing custom (non UL) solutions to meet new requirements should
be over.  If this is to be a national requirement, the industry should be
mature enough to offer multiple solutions for code compliance.  I'm all for
improving safety, but it needs to be done as an industry: together,
incrementally.

R.Ray Walters

CTO, Solarray, Inc

Nabcep Certified PV Installer,

Licensed Master Electrician

Solar Design Engineer

303 505-8760

On 3/15/2016 1:48 PM, Patrick Shortell wrote:

Dear List,

Maybe it's an over simplistic opinion, but shouldnt all sources be
disconnected rapidly in an emergency situation.

We can always do better than what the code requires. I get frustrated when
people go to the book, (and try to hide behind the text).  instead of
thinking through real life scenarios.

There are simple ways to work around these issues.

I find when something is questionable, Ill call the AHJ and get his
approval First.

What would I do in my own house?

What if someone thought all the power was off when they dragged a hoseline
into my basement.

My two cents

Pat

On Tue, Mar 15, 2016 at 1:10 PM, <billbrooks7 at sbcglobal.net> wrote:

Ray,

I guess I have to step in after that acknowledgement. PV system circuit is a
self-defined term and therefore cannot be defined unless you are going to
develop a meaning that is different from the self-definition. It means ANY
circuit in a PV system. This includes battery and stand-alone circuits in
the 2014 NEC.

The language of the 2014 NEC was a compromise between the fire service and
the PV industry.  Originally, the language required essentially module-level
shutdown. I raised the concern with the PV industry to get them involved
since most were not paying attention at the time. This language was
developed and intended to cover all circuits in a PV system. In the 2014
NEC, batteries are part of a PV system and therefore fall under this
requirement.

In the 2017 NEC, we were very careful to carve out all batteries and loads,
that were previously part of PV systems, and place them in their own
articles. Don't shoot the messenger on this one and don't think for a minute
that I alone made this requirement or am alone in interpreting it in this
way. I did author this compromise with other representatives of the PV
industry so I think I know what the intent was.

It is understandably difficult for battery systems and I would try to keep
battery circuits as short as possible. The 5-feet was intended to match the
requirement of 690.71(H)--which is further evidence of the intent of the
2014 NEC.

The 2017 NEC removes batteries from the requirement, but they still cannot
backfeed the PV array. Energy storage systems (Article 706) will have their
own requirements in time--that is guaranteed.

Bill.

-----Original Message-----
From: RE-wrenches [mailto:re-wrenches-bounces at lists.re-wrenches.org] On
Behalf Of Ray Walters
Sent: Tuesday, March 15, 2016 9:02 AM
To: RE-wrenches <re-wrenches at lists.re-wrenches.org>
Subject: [RE-wrenches] Rapid Shutdown

Greetings Esteemed Wrenches:

I've just heard back from our inspector here in Colorado, and we are still
being required to disconnect the batteries under 690.12.  No where in 690.12
are batteries mentioned, nor in the appropriate 690.71 section that deals
with batteries.  The entire reasoning behind this is based on a single
article written by a single person: Bill Brooks.  I have contacted both
Outback and Magnum on this issue, and their engineers are unaware that rapid
shutdown applies.
My interpretation is that I could install an inverter and battery system
that was charged from a generator, and we would not need any rapid shutdown
at all.  But according to Bill, as soon as I put a single solar module into
the system, suddenly the entire system becomes PV? The problem lies with the
term 'PV System circuit'  used in 690.12.  690.2 Defines 'PV Output
circuit', and 'PV source circuit', but there is no 'PV system circuit'
defined.  690.12 therefore uses an undefined term.
Our design uses 2 inverters, so if we used Midnite's E panel with their
remote trip breakers, the 2nd inverter would be more than 5 ft from the
batteries.  If we used Magnum or Outback DC disconnects (that would comply
with the 5 ft rule specified in 690.71) they don't offer remote trip.
We have a Midnite Rapid disconnect Combiner on the roof with the Birdhouse,
so we are complying with 690.12, it should not be applied to batteries
though.

Thanks,

--
R.Ray Walters
CTO, Solarray, Inc
Nabcep Certified PV Installer,
Licensed Master Electrician
Solar Design Engineer
303 505-8760

_______________________________________________
List sponsored by Redwood Alliance

List Address: RE-wrenches at 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 at 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

-- 

Patrick A. Shortell

*Licensed Master Electrician*

*Certified Solar Installer*

71 Oregon Street

Long Beach N.Y. 11561

cell: 516-477-0221

_______________________________________________

List sponsored by Redwood Alliance

List Address: RE-wrenches at 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 at 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
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20160315/e43aa3d0/attachment-0002.html>