[RE-wrenches] Buck-Boost transformer to mitigate high voltage drop?

[Chris Mason]

Just a note: AIC has nothing to do with breaker trip amperage ratings or
nuisance tripping, it has to do with the ability of the switchgear to
interrupt very large fault currents for very short periods such as you
would find close to a utility transformer with very low impedance in the
event of  service failure. AIC ratings go from 10,000 amps to millions.

Buck/boost and Step up/step down are the same thing.

On Tue, Aug 16, 2016 at 1:59 PM, William Miller <william at millersolar.com>
wrote:

> Chris:
>
>
>
> If you do provide transformers I think they are called step-up/step down.
> Buck/boost transformers I believe are to make adjustments to voltages.
>
>
>
> I have learned that you need to account for the current flow and
> direction.  For one-way flow, the upstream transformer has a slightly
> different turns ratio than the downstream transformer to account for
> voltage drop.  With two-way current flow, you might want to consult an
> engineer (application or electrical) to determine the best, most efficient
> transformer pair.  You can incur a lot of losses with transformers so
> design is critical.
>
>
>
> One other complication can occur:  In-rush currents can cause nuisance
> beaker tripping.  You may need to buy a breaker with higher AIC rating to
> compensate for this.
>
>
>
> Also, I bought a transformer from a reputable manufacturer that had
> mis-labeled terminals.  The smell was hard to forget.  I suggest you
> ohm-out any transformer to identify terminals on the same and different
> windings.
>
>
>
> In general, this kind of project can have some unforeseen complications.
> I am not that experienced, but the experience I do have has come at some
> cost.  I hope to help you and fellow wrenches avoid some of that pain.
>
>
>
> Sincerely,
>
>
>
> William Miller
>
>
>
> [image: Gradient Cap_mini]
> Lic 773985
> millersolar.com <http://www.millersolar.com/>
> 805-438-5600
>
>
>
> *From:* RE-wrenches [mailto:re-wrenches-bounces at lists.re-wrenches.org] *On
> Behalf Of *Chris Mason
> *Sent:* Tuesday, August 16, 2016 10:39 AM
> *To:* RE-wrenches <re-wrenches at lists.re-wrenches.org>
> *Subject:* Re: [RE-wrenches] Buck-Boost transformer to mitigate high
> voltage drop?
>
>
>
> How much of the power produced will be self-consumed, how much will be
> exported?
>
>
>
> On Tue, Aug 16, 2016 at 12:16 PM, Howard Arey <scot.arey at solarcentex.com>
> wrote:
>
> Good day,
>
>
>
> I have a potential client that has an existing 1,000 foot run from the
> meter and transformer at the street to the home. This is 4/0 Al and quick
> calcs show the voltage drop at over 12%. He acknowledges that the wire is
> undersized to keep voltage at/about 240 volts (I have not measured directly
> at the street / transformer yet).
>
>
>
> I know the wire has the necessary ampacity to carry his current service
> needs and to carry amps from the to-be-suggested solar system.
>
>
>
> My concern is that the voltage drop will change the 240 volts at the
> street/transformer/meter to 211ish (or will I see a higher 268’sh voltage
> at the far house end?) at the house. The inverter will try to synch to this
> voltage but of course this is outside of typical inverter parameters.
>
>
>
> So, instead of re-running much large wire, does anybody have experience
> and comments about potentially using a buck-boots transformer at the home
> to get us back to 240 volts? This would need to be service entrance sized.
>
>
>
> *Howard “Scot” Arey*
>
> Owner, Solar CenTex
>
> 254-300-1228
>
> scot.arey at solarcentex.com
>
>
>
>
> _______________________________________________
> 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
>
>
>
>
>
> --
>
> Chris Mason
>
> NABCEP Certified Solar PV Installer™
>
> Solar Design Engineer
>
> Generac Generators Industrial technician
>
>
>
> www.cometsolar.com <http://www.cometenergysystems.com>
>
> 264.235.5670
>
> 869.662.5670
>
> Skype: netconcepts
>
> _______________________________________________
> 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
>
>
>


-- 
Chris Mason
NABCEP Certified Solar PV Installer™
Solar Design Engineer
Generac Generators Industrial technician

www.cometsolar.com <http://www.cometenergysystems.com>
264.235.5670
869.662.5670
Skype: netconcepts
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20160816/95f3d244/attachment-0002.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image002.jpg
Type: image/jpeg
Size: 1460 bytes
Desc: not available
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20160816/95f3d244/attachment-0004.jpg>