which of these 2 panels would you buy?

[defed]

i have been searching around for good prices on panels for a while now...i found some local and some that would have to be shipped.

the local ones are non-branded suntech, 250w, 72 cells, 24v (34+v @ 7+a).  the guy doesn't have any spec sheets/literature for them and is offering his own 5 yr warranty.  the cost is $2.50/w plus tax.  total is about $2.70/w.

the shipped ones are BP, 175w, 24v, (36+v @ almost 5a).  the seller claims they have the 5 yr warranty on workmanship and the 25 yr on power (90% @ 12 yrs, 80% @ 25 yrs).  cost is just over $2/w plus shipping for a total of about $2.70/w.

for all intents and purposes, the 2 are of equal price.  if i bought 3 BP's, i'd get slightly more power for the same cost due to decreased shipping on 3 panels, but don't know if i want to start off w/ an odd # of panels.  they would be series w/ a MPPT controller (into 24v battery), so for now it wouldn't be a problem, but maybe in the future if i add on.

i'm a bit worried about the no warranty on the suntech's.  if one was to buy branded suntech's, is there a warranty on them?  does a warranty really do much good 10 yrs from now?  i mean, do i have to pay to ship the panels back to get a pro-rated discount on new ones and pay to have them shipped to me again?

any opinions/advice will be appreciated, thanks.
Dave

[ghurd]

VF posted something more than relevent a long time ago.
Maybe he can still find it.

Anyway-

Might want to read what you posted!

"i'm a bit worried about the no warranty on the suntech's"
"if one was to buy branded suntech's, is there a warranty on them? "
Thats a conundrum.
If they were branded they would not be suntechs, would they?
If the 'brand' that manufactured them had faith in them lasting 5/10/15/20/25 years, then they would have put their own name brand on them instead of selling them to 'the dude' at a super discounted price.


"non-branded suntech, 250w, 72 cells, 24v (34+v @ 7+a).  the guy doesn't have any spec sheets/literature for them and is offering his own 5 yr warranty"
So 'some dude said on the phone' admitted  he doesn't know what he has, but if something happens in 5 years... he himself will make it good?

"the shipped ones are BP... for all intents and purposes, the 2 are of equal price..."
So this dude is about equally financially stable as BP?
If $100K worth of PVs go belly up, the dude and BP will be equally able to rectify the issue?

BP was willing to put their name, data sheets, warranty, etc on one panel.
Some guy who has no idea what the data sheets look like said... what?

And "for all intents and purposes, the 2 are of equal price".

"don't know if i want to start off w/ an odd # of panels"
Correct.
Bite the bullet now.  Get it over with.
Buy 4 BPs.

[defed]

thanks Ghurd.  i thought suntech made panels w/ their own name on them...these were made by suntech, or at least used suntech cells (stp), just didn't have a name on them anywhere.  figured they were 'B' grade and never bothered to get a label.

i did know more about the panels than he did...even i can read a data plate.

i guess it makes perfect sense to get BP panels since they do cost the same in the long run...just not sure i can get 4 BPs and the MPPT all at once, that's pushing $2k.

the only advantage to the local guy is not having to have them shipped and ending up w/ damage....but that seems to be a small advantage overall.

[defed]

ok, i think i found a deal i may be able to live with...

4 BP 175w panels and either a Morningstar TS-MPPT-60, Outback FM-60 or Xantrex XW-MPPT60-150 for about $3.29/watt including delivery.  total is a little more than i wanted to spend initially, but buying 4 panels now saves me about $200 in shipping later...just need to decide on which MPPT controller to get.

[DanG]

Retail is a little more but volume vendors have them more reasonably... for the cost difference I might be tempted to go with the 80A Outback product - yaaaa, 2880 vs. 3840 watt handling at 48V is a lot of PV but the 720 vs. 960 @ 12V is more inline with starter systems. I have the older Outback MX60.

[Volvo farmer]

I can vouch that I got excellent warranty service when one of my BP panels got a blemish in it. Basically, ten minutes on the phone and some forwarded pictures of the damage got me a brand new panel shipped pronto.

[defed]

Retail is a little more but volume vendors have them more reasonably... for the cost difference I might be tempted to go with the 80A Outback product - yaaaa, 2880 vs. 3840 watt handling at 48V is a lot of PV but the 720 vs. 960 @ 12V is more inline with starter systems. I have the older Outback MX60.

$78 difference between the 60a and 80a outback, guess it's not much considering the overall cost.  the 60a units are all the same price.  i will be using 24v min bank and maybe 48v in the future.

other than the capacity of the 80 vs 60, is there any real difference between the 60a units that would make one more favorable than the others?

[defed]

I can vouch that I got excellent warranty service when one of my BP panels got a blemish in it. Basically, ten minutes on the phone and some forwarded pictures of the damage got me a brand new panel shipped pronto.

did you have to pay any of the shipping costs for the replacement?  either shipping the old one back or getting the new one?  good to hear it was resolved easily.

[dbcollen]

I was speaking to Robin Gudgel at Solwest in oregon, he told me that the new morningstar MPPT60 is currently the best MPPT on the market, till the Classic comes out. It has built in ethernet for monitoring.

Dustin

[Volvo farmer]

did you have to pay any of the shipping costs for the replacement?  either shipping the old one back or getting the new one?  good to hear it was resolved easily.

Nope, no shipping either way. Plus they shipped it 2nd day air, which I didn't even request.  This was for the 5 year materials/workmanship warranty, not the rated power warranty.

I was speaking to Robin Gudgel at Solwest in oregon, he told me that the new morningstar MPPT60 is currently the best MPPT on the market, till the Classic comes out. It has built in ethernet for monitoring.

Ouch! I wonder what the guy who designed the MX60 would have to say about that 

[defed]

I was speaking to Robin Gudgel at Solwest in oregon, he told me that the new morningstar MPPT60 is currently the best MPPT on the market, till the Classic comes out. It has built in ethernet for monitoring.

Dustin

does "the new morningstar mppt60" mean that there is an OLD version of this model?  or is it just newer in general than the other brands?

one thing that is really bugging me, i can't find any info or pics of it....how do you get from the MC3/4 connectors at the panel to bare wire at a combiner box/controller?  i don't see any cables w/ the MC on one end and something else on the other.

[defed]

it appears the the panels i want to get are not compatible w/ the MPPT 60....tho i don't see why not.

this site has links to each mfg's calculators:

http://www.altestore.com/howto/Solar-Power-Residential-Mobile-PV/Solar-Components/Sizing-MPPT-Charge-Controllers/a61/

the morningstar site doesn't have my model, so i enter the data from here:

http://sunelec.com/Specs/BP/SX3175NQ.pdf

record low temp here is -20F, i used 77F as avg high, but i doubt it's even quite that high.  results come back as incompatible.

outback does not list those panels, and you can't manually enter data.  xantrex does list that model and looks compatible for up to 4 strings of 2 modules in series.

i don't understand why they aren't compatible w/ the morningstar.  it must miss some criteria, but not sure what yet.

[defed]

ok, i think i figured it out....the spec sheets list the VOC coefficient as -160mV....the morningstar site wants it in V....so if i enter -.16, it IS compatible!

[DanG]

remember the + / - .020 tolerance & add that in for worse case...

[defed]

ok, i take it the more - the # is the worse it is.  if i use -.18, the mppt is barely adequate as i can only use 2 panels in series, and 2 strings in parallel.  the other 2 (outback and xantrex) seem to allow up to at least 4 pairs in parallel.

[ghurd]

What is the problem?  Voc? 
The MorningStar is over-voltage protected.  Under those conditions, the controller keeps working, at a reduced efficiency.  Sounds like a snubber circuit of some type.
(The calculator tool loads a little less every time I try)

Not sure how you figured 2 pair for one, 4 pair for the others, unless you were comparing the 45A to the 60 and 80A units?
G-

[defed]

you are correct Ghurd...when i was trying to figure out why the modules were incompatible, i changed battery voltage to 12, and forgot to change it back to 24v.  now it says 4 strings of 2 pair is optimal.  i was confused about why too, then i studied the reason WHY it was too much, was over wattage which clicked that i was at 12v.

now i guess i'm back to all 3 choices again  haha!

[SteveCH]

I have several brands of panels in my arrays. Two of them are BPs. Those two were a bit higher in cost than the others [all of mine have been bought over a period of 25+ yr., so exact cost per watt isn't completely a fair comparison here for my arrays]. The BP panels are excellent. I'd have more except that the last time I purchased panels, nine of them, there was a shortage in the US and I found truckloads of Kyocera and not much of anything else at the particular moment I needed them. Or, I would have gone with BP. [By the way, I have been very happy with the Kyoceras.]

I bought something from Morninstar a few yr. ago and when I had a question about it, I was able to speak with someone over the phone, no delays or hassles and he gave me all the info' I wanted, plus some. Very good experience. I do not have their controller, so cannot give a report on it, but the products I do have are also excellent and a great value for the cost.

[dbcollen]

VF,

The Gudgel brothers designed the MX-60   
 He said the xantrex MPPT has a single channel converter, the MX has 2 chanels, and the Morningstar is 3 channel, the morningstar has higher conversion efficiency because it uses the best converter(s) for the present load.

Dustin

[defed]

anyone using a remote temp sensor for the batteries?  i have read that it is vital if the temp difference between where the batteries and controller are is greater than 5C, you need a temp sensor.  at some point, they will be in different areas, which could very well experience a temp difference.

i see morningstar sells one pretty cheap...says it works for various models of their controller, including tristar...does that include the tristar mppt-60?  suppose that might be a question for morningstar.