[RE-wrenches] offgrid system question

Tue Aug 19 17:57:03 PDT 2008

Thanks Phill, 
I have often thought that I should have compiled such a list from my experiances, but of course we are always to busy to do so.  

Could you add a few words to your post
For the chop saw, type & manfactureer, and how was the surge attained? I assume it is just turning on of the saw no load at switch on? , or was it the peak as the saw cut onto the log.  

On the others similar and was the surge when one device was turned on? of the set? or were all turned on together?  

Another interestering datum would be what is the surge currents doing the same experiments using the grid.

Thanks Darryl

--- On Tue, 8/19/08, Phil Undercuffler <P.Undercuffler at conergy.us> wrote:

> From: Phil Undercuffler <P.Undercuffler at conergy.us>
> Subject: Re: [RE-wrenches] offgrid system question
> To: "RE-wrenches" <re-wrenches at lists.re-wrenches.org>
> Date: Tuesday, August 19, 2008, 11:12 AM
> Peter, that's a very good point.  There are laws of
> physics involved
> with inverter design, and all products have a hard limit in
> ability to
> process Volt-Amps.  One way inverter manufacturers can get
> higher
> starting current is to allow the voltage to sag.  My old
> DR2424 could
> start my 2hp 120v tablesaw, but it darned near turned off
> the lights in
> doing so, the voltage dropped so low.
> 
>  
> 
> Unfortunately, there are no published specifications for
> voltage sag
> that I've ever seen, other than some manufacturer
> provided comparison
> curves used in various presentations.  Not exactly fair and
> unbiased, to
> be sure.  Admittedly, the equipment needed to gather this
> type of data
> is pretty spendy; not every wrench is going to have access
> to that type
> of hardware, so we're somewhat at the mercy of the
> manufacturers.
> 
>  
> 
> We had the opportunity here in our training room to play
> with the major
> products side-by-side this past fall, and looked
> specifically at voltage
> regulation when under surge loads.  We focused on voltage
> stability in
> unbalanced conditions - heavy surge loads on one phase,
> minimal loads on
> the other.  Voltage measurements were via two Fluke
> 87's in Min/Max
> mode, current via Techtronix digital scope, clamp meter
> input.  In
> short, the XW had the best voltage regulation and highest
> surge
> capability of the tested products, and the Magnum was
> impressive in its
> ability to start loads well beyond its rated capacity but
> your client
> better not be working on the computer when the well pump
> kicks on. 
> 
>  
> 
>  
> 
> Loaded phase
> 
> Unloaded phase
> 
> Loaded phase
> 
> Unloaded phase
> 
> Loaded phase
> 
> Unloaded phase
> 
> Loaded phase
> 
> Unloaded phase
> 
>  
> 
>  
> 
>  
> 
>  
> 
>  
> 
>  
> 
>  
> 
> XW6048
> 
> Dual VFX3648 OB Stacked
> 
> MS4448AE
> 
> Dual SW5548
> 
> Chopsaw alone
> 
> A peak
> 
> 96 A
> 
> 110 A
> 
> 50 A
> 
> 94 A
> 
> V max
> 
> 122.4
> 
> 123.2
> 
> 124
> 
> 127.2
> 
> 128.8
> 
> 132
> 
> 124
> 
> 124.8
> 
> V min
> 
> 108.8
> 
> 112.8
> 
> 116
> 
> 116
> 
> 81.6
> 
> 87.2
> 
> 109.6
> 
> 118.4
> 
> V Delta
> 
> 13.6
> 
> 10.4
> 
> 8
> 
> 11.2
> 
> 47.2
> 
> 44.8
> 
>  
> 
>  
> 
> 2 Electric heaters (not metered), compressor, chopsaw,
> planer. 
> 
> A peak
> 
> 127 A
> 
> 128 A
> 
> 88.5 A
> 
> Overload shutdown
> 
> V max
> 
> 124.8
> 
> 132.8
> 
> 124
> 
> 129.6
> 
> 144.8
> 
> 142.4
> 
> V min
> 
> 99.2
> 
> 105.6
> 
> 97.6
> 
> 105.6
> 
> 60.8
> 
> 72
> 
> V Delta
> 
> 25.6
> 
> 27.2
> 
> 26.4
> 
> 24
> 
> 84
> 
> 70.4
> 
>  
> 
>  
> 
> 2 Electric heaters (not metered), 2 compressors, 2 routers,
> chopsaw,
> planer.
> 
> A peak
> 
> 133 A*
> 
> 130 A*
> 
> 93 A
> 
> Overload shutdown
> 
> V max
> 
> 125.6
> 
> 132.8
> 
> 126.4
> 
> 131.2
> 
> 154.6
> 
> 142.4
> 
> V min
> 
> 96
> 
> 103.2
> 
> 92.8
> 
> 102.4
> 
> 59.2
> 
> 70.4
> 
> V Delta
> 
> 29.6
> 
> 29.6
> 
> 33.6
> 
> 28.8
> 
> 95.4
> 
> 72
> 
>  
> 
>  
> 
>  
> 
>  
> 
>  
> 
>  
> 
>  
> 
>  
> 
>  
> 
>  
> 
>  
> 
> *Circuit breaker tripped
> 
>  
> 
>  
> 
>  
> 
>  
> 
>  
> 
>  
> 
>  
> 
> I'm hoping the above clip-n-paste from a spreadsheet
> transfers over in
> this email, now that the Wrenches isn't limited by
> Topica plain text
> format.  However, if this email shows up without numbers in
> the
> paragraph above, please let me know and I'll re-send
> after re-typing.
> :-(
> 
>  
> 
>  
> 
> Phil Undercuffler
> 
> Director, Battery-based and Off-grid
> 
> Conergy Sales & Systems, Americas
> 
> Our World Is Full of Energy
> 
> 1730 Camino Carlos Rey Suite 103
> 
> Santa Fe, NM  87507
> 
> p.undercuffler at conergy.us
> <mailto:p.undercuffler at conergy.us> 
> 
> Direct | 505.216.3841
> 
> Toll Free | 888.396.6611 x4841
> 
> Fax | 505.473.3830
> 
> www.conergy.us <http://www.conergy.us/> 
> 
> ________________________________
> 
> From: re-wrenches-bounces at lists.re-wrenches.org
> [mailto:re-wrenches-bounces at lists.re-wrenches.org] On
> Behalf Of Peter
> Parrish
> Sent: Tuesday, August 19, 2008 8:57 AM
> To: 'RE-wrenches'
> Subject: Re: [RE-wrenches] offgrid system question
> 
>  
> 
> I haven't been following this thread carefully, too
> busy, but my advise
> is, don't focus on current capability alone. From
> Xantrex, find out the
> "voltage compliance" as well. By that I mean,
> "What is the voltage at 52
> amps output? Does it vary over time from 1 msec to 5
> sec?" Any motor
> will need both a voltage and current to operate properly,
> and they tend
> to draw more and more current as the source (inverter)
> voltage drops. 
> 
>  
> 
> - Peter
> 
> Peter T. Parrish, President
> California Solar Engineering, Inc.
> peter.parrish at calsolareng.com 
> 
> ________________________________
> 
> From: re-wrenches-bounces at lists.re-wrenches.org
> [mailto:re-wrenches-bounces at lists.re-wrenches.org] On
> Behalf Of Phil
> Undercuffler
> Sent: Tuesday, August 19, 2008 7:40 AM
> To: RE-wrenches
> Subject: Re: [RE-wrenches] offgrid system question
> 
>  
> 
> The XW6048 is rated at 52 amps RMS line to line between 5
> seconds down
> to 1 millisecond, so if your client's AC has a starting
> inrush surge of
> 104 amps at 240v, then yep, I think your biggest problem is
> not enough
> inverter.  Sounds like just one additional inverter will be
> marginal;
> depending upon the additional background loads you may want
> to consider
> expanding to three total.  I think Mick Abraham is right on
> here, in his
> earlier post.
> 
>  
> 
> Phil Undercuffler
> 
> Director, Battery-based and Off-grid
> 
> Conergy Sales & Systems, Americas
> 
> Our World Is Full of Energy
> 
> 1730 Camino Carlos Rey Suite 103
> 
> Santa Fe, NM  87507
> 
> p.undercuffler at conergy.us
> <mailto:p.undercuffler at conergy.us> 
> 
> Direct | 505.216.3841
> 
> Toll Free | 888.396.6611 x4841
> 
> Fax | 505.473.3830
> 
> www.conergy.us <http://www.conergy.us/> 
> 
> ________________________________
> 
> From: re-wrenches-bounces at lists.re-wrenches.org
> [mailto:re-wrenches-bounces at lists.re-wrenches.org] On
> Behalf Of Max
> Balchowsky
> Sent: Tuesday, August 19, 2008 6:45 AM
> To: mick at abrahamsolar.com; RE-wrenches
> Subject: Re: [RE-wrenches] offgrid system question
> 
>  
> 
> You're right Mick, It is an XW 6048, there's only
> one and I really think
> I'm going to find that the biggest problem is that
> there is not enough
> inverter capacity capacity with just one unit (the scematic
> shows a 60
> amp breaker on the output). The system is new ( installed
> within the
> last 4 months and the batteries were new) The AC unit is
> 240 volt.....
> 
>  
> 
> Max Balchowsky
> 
> SEE Systems
> 
>  
> 
>  
> 
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