[RE-wrenches] Shunt question

[Mick Abraham]

Greetings, all~

Regarding Allan's shunt question: Definitely you will need the same "ratio"
for the meter logic to work right.

I have purchased from AEE Solar a 1000 amp shunt that drops 100 mv @ 1000
amps. This is the same "ratio" as a shunt that drops 50mv @ 500 amps. The
photo makes this appear to be just a block of metal with no insulating base
but I confirmed and found that it did arrive on a plastic base. I had to do
some major mods to fit this into the Schneider XW "power distribution
panel" because the overall height and other dimensions are different, but
it worked out.

I do not recall the part number for this but the AEEsolar website has a
pretty good search function. Allan, you may contact me off list as always
if I may assist further.

Jolliness,

Mick Abraham, Proprietor
www.abrahamsolar.com

Voice: 970-731-4675



>    1. Shunt question (Allan Sindelar)
>
>
> ---------- Forwarded message ----------
> From: Allan Sindelar <allan at positiveenergysolar.com>
> To: RE-wrenches <re-wrenches at lists.re-wrenches.org>
> Cc:
> Date: Tue, 31 Jul 2012 07:37:55 -0600
> Subject: [RE-wrenches] Shunt question
>  Wrenches,
> What are you using when you need a shunt larger than the standard
> 500A/50mV?
>
> The application: four Sunny Islands and a Radian in a large grid-tie with
> backup system. Total current flow through B- is rated 850A (using 125A SI
> DC breakers) or 1,050A (using 175A DC breakers) on a single large battery
> bank. Given uncertain continuous amperage, I should use a 1,000A shunt or
> even a 1,200A shunt, as Deltec recommends never exceeding 67% of a shunt's
> current rating for long. Deltec makes both; see
> http://www.deltecco.com/MKC-DC.html. The shunt will be installed inside
> of a Nottagutter-8, with a Midnite shunt bus on each side. The shunt will
> be used with the Sunny Island master to control overall SOC and charging
> parameters; there's no plan for a Tri-Metric in this system, as a Sunny
> Webbox will handle online monitoring per the customer's wishes.
>
> The 1,000 and 1,200A series MKC Deltec shunts are the same physical
> dimensions as the common 500A/50mV units. However, the larger units are
> still 50mV. Ralph Heisey of Bogart Engineering, in his "Information on
> Shunts" reference article (http://www.deltecco.com/MKC-DC.html), tells us
> to match the ratio of voltage drop to current - that is, just as a 500A
> shunt drops 50mV, a larger shunt with 1,000A flowing through it should drop
> 100mV. But all of the larger Deltec shunts are still rated 50mV.
>
> Who has done this and resolved the issue? What shunt did you use?
>
> Thank you,
> Allan
> --
> *Allan Sindelar*
> *Allan at positiveenergysolar.com* <Allan at positiveenergysolar.com>
> NABCEP Certified Photovoltaic Installer
> NABCEP Certified Technical Sales Professional
> New Mexico EE98J Journeyman Electrician
> Founder and Chief Technology Officer
> *Positive Energy, Inc.*
> 3209 Richards Lane (note new address)
> Santa Fe, New Mexico 87507
> *505 424-1112*
> *www.positiveenergysolar.com* <http://www.positiveenergysolar.com/>
>
> *
> *
>
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