Solar Panel Questions

[cujet]

I recently purchased some panels at SunElec in Miami. I was interested in the cheapie, blem panels and drove all the way down there to get them. After looking at the blems, I just could not do it. They assured me the panels would make 100% of rated power. But, looking at the cells, I can't see how. Some of the cells had chips and cracks that were large enough to affect operation. Plus they were ugly.

I ended up spending more, getting less power, but I have "A" rated Chinese panels, rather than "B" or "C".

[WStayton]

cujet:

  About the Sunelec panels:

  I am under the impression that they warrant their "blem" to match the performance of the cosmetically perfect panels and tha they will replace them if they don't perform to the level.

  Is this NOT your understanding???

  I read their gaurantee and just sort of figured if they were willing to replace them at their expemse, if they didn't perform to the same standard as the "perfect"panels, I couldn't get hurt!

  Now your making me nervous - in as much as I am about to have $5,000 at risk!  <grin>

  I am most curious as to what your understanding is of their "warranty".

Regardz,

Wayne Stayton

[mike90045]

mike90045:

  About the Xantrex XW6048:

  Doesn't the Inverter/charger use the Xanbus to communicate with/through the the XW solar charge controller to charge the batteries from its (i.e. the Inverter/Charger's) battery charger???

  I had thought that if I put something other than a Xantrex charge controller in the system, the Inverter/Charger would just default to some "safe" charger algorithm and you wouldn't have access to the various "flavors"/varietes of charging programs???

  Or am I again laboring under a misconception?   

No troubles at all without using the xanbus.  The solar charger charges as if it was alone - full power to the batteries, or whatever the battery state of charge calls for , as long as there is enough sun.

If batteries are low, and you crank up the genset, the XW6048 also can sense the state of charge, and charge the batteries as needed too.   You could be running both full bore on a sunny day - but why ?

About the MidNite Solar Classic 150 MPPT Charge Controller:

  When I look at the site you posted, I find:

Model Number   150   200   250   250KS   
Op Volts Input   150VDC 200VDC   250VDC   250VDC   
Bat Chg Volts   12-93 Volts   12-93 Volts   12-93 Volts   12-150    
Max Current O/P
at 25°C (77°F)   96A @ 12V   74A @ 12V   60A @ 12V   40A @ 120V   
                          94A @ 24V   70A @ 24V   62A @ 24V   
                          83A @ 48V   65A @ 48V   55A @ 48V   
De-rated Current
at 40°C (104°F)   80 Amps   66 Amps   52 Amps   33 A
   
Environment   -40°C to 40°C (-40°F to 104°F)   

   And you say:  "Midnight Classic 150  http://www.solar-electric.com/mnclassic.html  is 96 amps, and with the "hyperVOC" it will take 198V on the input (w 48V battery bank)"

  Where did the 198V input come from???  The 96A/80A unit shows  150 V for the max input in the chart above . . . It LOOKS, to me, like the only way you can get to a higher input voltage is to use one of the smaller current versions of the unit, no???


  So, if I put the Midnight unit in the mix and just wire the Xantrex Inverter/Charger as though it wasn't there, from a data standpoint, what will the Xanterex do for Generator/Line Charging?  Does it care that you don't have a Xantrex Solar Charger in the path???  Will the Inverter/Charger still let you taylor the charging functions to your particular battery bank?

   If the Midnight will allow the Xantrex Inverter/Charger to perform all of its functions, despite not being able to communicate with the Solar Charger, I THINK I am willing to spend the $100+ extra for the Midnight instead of a Xantrex solar charger.

  You seem to be good at turning things upside down - a least for a simple mind like mine!  <grin>

  I await you response!

  Thanx for the input, BTW - its good to have an EE looking at what our doing so you don't do something stupid!!!! <smile>

Regardz,  Wayne Stayton 

Read the Classic manual - HyperVOC is the standard unit voltage (I'm using the 150, since that's the one I'd use with the panels you have)  PLUS the battery voltage, is what the array can safely supply the controller.  You don't need the 200 or 250, your array is only 140nominal, and the 48V gives you a good safety margin, and the de-rate amps at 80A, keeps the NEC happy.

[WStayton]

mike90045:

  Ok, you have convinced me!!!

  Now to go figure out who has the best price for the "NEW" battery solar charger!  <grin>

  Oh, and to tear up, yet again, still more already, the order to Sun Electronics - presuming somebody responds about their "warranty".

  Thanx for holding my hand - lack of knowlege is such a limiting disability!  <grin>

Regardz,

Wayne Stayton

[cujet]

cujet:

  About the Sunelec panels:

  I am under the impression that they warrant their "blem" to match the performance of the cosmetically perfect panels and tha they will replace them if they don't perform to the level.

  Is this NOT your understanding???

  I read their gaurantee and just sort of figured if they were willing to replace them at their expemse, if they didn't perform to the same standard as the "perfect"panels, I couldn't get hurt!

  Now your making me nervous - in as much as I am about to have $5,000 at risk!  <grin>

  I am most curious as to what your understanding is of their "warranty".

Regardz,

Wayne Stayton

Here is my "take".

First off, I have no understanding of the warranty issue, other than to say there is a some chance the manufacturer will probably be out of business by the time the panel fails. So, other than paying for a name brand, Sanyo or Sharp panel, I simply assume a cheap panel warranty is useless.

Second, the panels I saw had cell fractures and cracks and missing sections that were into the tracings. How this could not affect real world performance I don't understand. OTOH, Maybe the panels are a touch under rated and it's built in to the panel's specs, so you actually get rated power. 

Put another way, they sell you a 200 watt panel, that would otherwise produce 220W with perfect cells. Dunno.

[WStayton]

cujet:

  About warranty:

  I THINK that Sun Electric is the one warrantying the panels, not the manufacturer - since they won't tell you who is the manufacturer! <grin>

  Their warranty says that they guarantee the performance for 20 years to not fall below the 90% of the rated output.

  Sun Electric has been around since sometime in the 1980's (?) so I don't THINK that they are a fly-by-night that will be here today and gone tomorrow, but you maybe right - if they fold up shop, their warranty is worth exactly zero - but that's true for anybody's warranty and, for a field such as solar equipment where EVERYTHING changes on a daily basis, the longevity of ANY manufacturer/retailer is a matter of conjecture.

  I suppose the smart thing to do is asses what you think that the probability of the guaranteeing angency's going bust is and work from there - my "back-of'the-envelope" assessment is that Sun Electric is PROBABLY going to be there for the forseeable future and their warranty IS worth the paper its printed on - but that's MY assessment, you obviously have made your own assessment and have come to a different conclusion, and operate in accordance with that assessment.

  I guess its sort of "different-strokes-for-different-folks"!  <grin>

  About "over-design/under-rating":

  I think that anybody, who builds ANYTHING on which they warrant the performance, makes the units so that they routinely over-perform, just so they don't get a bunch of hard-a$$#s who demand warranty when the performance drops to 0.01% below spec.  How much they build in for Mom and the underwriters is another matter entirely, but the nunber that I have seen used for solar panels is that they routinely outperform/overperfom sepcifications by about 10% when new, so there is "some" margin for breakage/error/mis-manufacture/etc. in the panels.

  I HOPE your assessment works out for you, and I SINCERELY hope mine works out for me! <smile>

Regardz,

Wayne Stayton

[bschwartz]

I don't know about their current panels, but they used to sell remanded evergreen panels.

[WStayton]

bschwartz:

  About the brand of panel:

  Actually, the panels in question turned out to be "Sovello SV-T-200's" by process of elimination to find the 200 watt panel that matched the specs that they gave - Sun Elec said they couldn't give out the name of the manufacturer, since they were "blems" but that if I matched up the model number and confirmed that the voltages and currents matched, I was good to go with what the "sizer" program gave me.

  So, after only sorting through about 40 different panels, and waiting for dial up to down load the info, I finally found it!  <grin>

  That was the easy part of the process!  <smile>

Regardz,

Wayne Stayton

[cujet]

I'll probably be going down to Sunelec again within a month or two (to purchase more panels). If you want me to take some pics, I'll do that.

[WStayton]

cujet:

  "I'll probably be going down to Sunelec again within a month or two (to purchase more panels). If you want me to take some pics, I'll do that."

  Trying to confuse me with the facts, AGAIN??? <grin>

  Thanx for the offer, but I'm anticipating having them in my hands in a couple of weeks.  Just as soon as they get my/the-bank's cashier's check, they will ship them and I don't think freight from Florida to NY is going to be more than a one week affair.

  I have, again, read their 4 MB Warranty, and I feel more or less confident that no matter how they look, if they don't perform that they will replace them - I can't find ANY references on the web to anybody who has had warranty claim problems with them and the BBB (what a joke!) has no pending/unresolved claims against them.

  I will advise, when they arrive, how they look, but I'm still a couple of months from having them screwed down on the roof and producing, so it will be at least that long before I know what their performance is.

  I DO appreciate the offer, though - Thanx!

Regardz,

Wayne Stayton