Solar Controller (cheap china)

Almot wrote:

Well, since we deviated into panels discussion...
Vmp/Imp exceeding the specs is not necessarily good. This Sharp in Solar Blvd guarantees +10/-5% accuracy of Vmp/Imp (and so does the unknown Perlight). -5% is a bit low if you happen to have it. +10% is too much deviation when you connect 2 panels, MPPT controller gets confused. I prefer having no more than +/- 3%. Not all the Sharps are that "bad", some models have +5/-0% tolerance. Frames of Sharp come in 4 different profiles see Figure 1 and corresponding model number, important thing when you use side brackets.

Never considered the tolerances and although great info, I'm not too concerned over that. I'm interested in getting a certain amount of Ah per day and anything over that is gravy. Having a larger battery bank does that for me. :) About Sharp panels, it meeting or exceeding its spec is great to me because that means it will at least put out its rated power or very close to it. Even though Perlight is cheap, I have no idea of its performance. I have a Trina panel bookmarked because of its wattage rating but no idea on performance.

westend wrote:
If their is any drawback to this module it would be that the Mfg., MX Solar has closed their US plant and warranty would be hard to get enforced if the module needed to be shipped back to Italy, their headquarters. I'm betting on the durability and quality of the module making that moot.

It would be cheaper to keep it than ship back to Italy. This is the growing problem in PV manufacturing - brands are shrinking, due to competition of no-names. And no-name won't be here for long either, by definition.

mena661 wrote:
X2. BTW, if I were buying, I'd probably get a Sharp because of the BFL's reports of getting right at and even over his panels rating. BUT, if a panel came up on sale and it was REALLY cheap, I might be tempted to get two or more of that one instead.

Well, since we deviated into panels discussion...
Vmp/Imp exceeding the specs is not necessarily good. This Sharp in Solar Blvd guarantees +10/-5% accuracy of Vmp/Imp (and so does the unknown Perlight). -5% is a bit low if you happen to have it. +10% is too much deviation when you connect 2 panels, MPPT controller gets confused. I prefer having no more than +/- 3%. Not all the Sharps are that "bad", some models have +5/-0% tolerance. Frames of Sharp come in 4 different profiles see Figure 1 and corresponding model number, important thing when you use side brackets.

Not much more waiting, controller arrived in NY FedEx.

Get your cheap controllers here

The OP's is $10.90 with free shipping.

Almot wrote:

mena661 wrote:
I forgot you were in Canada. Different price structures up there. Anywho, $150 for a 230W panel from Perlight Solar. You can also get a Sharp 250W for $212 if you want "name brand".

I meant US prices, this is where I picked it up, when going to where I needed them, which is Mexico. No-name panels I didn't even consider, when panel doesn't live up to expectations, replacing it in the middle of nowhere would cost a fortune in shipping and taxes. Solar Blvd had some no-name last year too, not this Perlight - some other name that is not there anymore. Trina was cheaper than now, though. If I were to buy a panel right now in the Solar Blvd - which is not where I bought - would rather pay extra for Trina. Don't remember what scared me off in Sharp back then, I think it was frame profile.

FWIW, I have the MX Solar 235w module from Solar Blvd. I purchased it when they had their "Black Friday" sale going on. This Made in USA module is currently $158. I am thinking of picking up another one at this low price. The frame is two conjoined metal pieces and is very strong (I drilled mine for a tilting mechanism and have had no trouble). If their is any drawback to this module it would be that the Mfg., MX Solar has closed their US plant and warranty would be hard to get enforced if the module needed to be shipped back to Italy, their headquarters. I'm betting on the durability and quality of the module making that moot.

Old & Slow wrote:
JR,

I see on another thread, you do not like parallel connections. I have found you to be pretty well straight up with your approach to this 'lectrical world of the RV folks. Well, in this case of Cheap China Controllers do you see perhaps an exception to your rule? Perhaps just adding controllers as needed?

O$S

RJ (JR) here. and I did say I don't like parallel connections, but only because its just an extra connections to corrode when at the batteries. The thing to do if you must parallel, it to do it at a junction block,.....away from the batteries. But JMO.

I've not seen over 11.2 out of my cheap china 2 panel 190 watts. Maybe less efficient than HI $ panels, I don't know. but I'm tickled to get even 10 amps out of this inexpensive system, I couldn't really care. 10 amps is going to do me just fine wintering in AZ. Here in OR,.......and on the coast,....well,......we ain't bragging, lets put it that way.

My expensive Sharp panel is rock solid supplying its 8.2 Isc while my cheaper Sun panels are all over the map (except above rating) for Isc.

Sun 100w is rated at 6.4a Isc, and say the "tolerance" is 5%. but I have measured anywhere from 6.0 to 6.4 while the Sharp is doing its steady 8.2 or 8.3 (so it is not haze or whatever keeping the Sun Isc low at the time) perhaps the Suns are more affected by temperature change or whatever, no idea.

But I do get at least 12a from the two 100s, adding whatever Isc they each feel like that day :) and am not upset over the missing 0.8 amp I should be getting with two 6.4s adding. Mena is right--the price is so good, you can live with these little things.

The Sun panels are physically light-weight per watt compared with the Sharp and part of that is having smaller gauge frames, but I suspect also their cells are not as thick or whatever. BUT, they work ok and were a great price. The Sharp panel also has a junction box with more diodes and terminals. Sharp stopped making these 12v panels a couple ago and now concentrate on the grid-tie market with big panels.

JiminDenver wrote:
Almot, I can see your point. Out in the middle of no where is no place to be testing out the unknown.

X2. BTW, if I were buying, I'd probably get a Sharp because of the BFL's reports of getting right at and even over his panels rating. BUT, if a panel came up on sale and it was REALLY cheap, I might be tempted to get two or more of that one instead.

Almot, I can see your point. Out in the middle of no where is no place to be testing out the unknown.