Using bare panels

cruiser guycruiser guy Solar Expert Posts: 87 ✭✭✭✭
I have 6 bare panels. I think these are 55 watt Sanyo panels from the mid-'90's. By bare I mean these are just the glass with the photovoltaic panels on it and a couple of pairs of tin connectors protruding from them. No diodes that I can see, no junction box, no frame, NOTHING but the panel.

What do I need to make these operational? I have a printout of the test results of some of these panels and that is where the Sanyo name and the 55 watt output figure comes from. Two of these in series should give me a nominal 12v (16v actual).
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Comments

  • JamesJames Solar Expert Posts: 246 ✭✭
    Re: Using bare panels

    sounds rather odd...are they crystalline or amorphous?
    6 volt?
  • mike95490mike95490 Solar Expert Posts: 8,250 ✭✭✭✭✭
    Re: Using bare panels

    At the very least, you have to seal them, and some frame material to stiffen up the glass.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • brandywinebrandywine Registered Users Posts: 15
    Re: Using bare panels

    you can get junction boxes all wired up and ready to go with diodes on eBay
  • brandywinebrandywine Registered Users Posts: 15
    Re: Using bare panels

    Also, there is a series of 3 videos on Youtube called Wiring a junction box to a solar laminate or something like that...on sunelec's youtube page. Watch them and you will know what to do.
  • bmetbmet Solar Expert Posts: 630 ✭✭
    Re: Using bare panels

    Not necessarily. The critical part where they are supposed to show the extraction of the bus wires is low light, blurry, and at the worst camera angle. Good thing they are aren't an AV company, they'd go broke.

    brandywine wrote: »
    Also, there is a series of 3 videos on Youtube called Wiring a junction box to a solar laminate or something like that...on sunelec's youtube page. Watch them and you will know what to do.
  • rgs03833rgs03833 Registered Users Posts: 16
    Re: Using bare panels
    I have 6 bare panels. I think these are 55 watt Sanyo panels from the mid-'90's. By bare I mean these are just the glass with the photovoltaic panels on it and a couple of pairs of tin connectors protruding from them. No diodes that I can see, no junction box, no frame, NOTHING but the panel.

    What do I need to make these operational? I have a printout of the test results of some of these panels and that is where the Sanyo name and the 55 watt output figure comes from. Two of these in series should give me a nominal 12v (16v actual).

    Before anything, get some DIODES... They are cheap, they are not only helping with testing your Panels but mostly protecting them from damages... brandywine... Made good sugestions, Good Luck! :D
  • brandywinebrandywine Registered Users Posts: 15
    Re: Using bare panels

    Yeah, and I love that lady speaking Spanish on the phone while filming dude's elbow---for 5 minutes.

    They are really bad quality; but if you know nothing, you can get a bit from it!

    Mickie & Travis
  • cruiser guycruiser guy Solar Expert Posts: 87 ✭✭✭✭
    Re: Using bare panels

    Crystalline or amorphous, how do I tell? Does it matter?

    Looked at the video on youtube. Now I know having four buss bars is normal!! The problem is on the panels I have the buss bars are at opposite ends of the panels. How will I know which buss bar is which?
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Using bare panels
    Crystalline or amorphous, how do I tell? Does it matter?

    Looked at the video on youtube. Now I know having four buss bars is normal!! The problem is on the panels I have the buss bars are at opposite ends of the panels. How will I know which buss bar is which?

    Label them 'A', 'B', 'C', 'D', et cetera.
    Place panels in sunlight.
    Use a meter to measure across every possible combination.
    Write down what you get, noting polarity.

    For instance 'A' to 'B' might read "+16 Volts" whereas 'A' to 'C' might read "0 Volts".

    Once you have that you should have a good idea of which is which in respect to the cells of the panel. They are probably two strings of cells meant to be connected in parallel to boost the over-all current or series to boost the over-all Voltage.
  • mike95490mike95490 Solar Expert Posts: 8,250 ✭✭✭✭✭
    Re: Using bare panels
    Crystalline or amorphous, how do I tell? Does it matter?? ....

    Yes, it matters

    Crystalline is typically a blue cell, with fine metal grids

    Amorphous is dark charcoal color, with long rows, and a single fine wire
    amorphous has a shorter lifetime, and often "fades" 10% a year, after 5 years
    you can be really low on power. But, is supposed to produce a little better in less than full sun.

    My opinions based on lots of chatter
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • nielniel Solar Expert Posts: 10,311 ✭✭✭✭
    Re: Using bare panels

    in addition to what mike said the amorphous are half as efficient as the crystalline types meaning you need twice the area to capture the same as a crystalline type would. with crystalline prices much lower now than years past they are by far the way to go.

    i decided to see what my us 64s are doing based on what mike said for degradation. they are 10-11 years old and i usually see about 46-47w at best with my classic mppt cc. this means a 30% reduction after 5yrs so 64w x .7 = 44.8w. i guess it's in the neighborhood of what mike indicates. crystalline can degrade too, but much slower. now this is 64w stc and we usually derate pvs anyway with an average figure of about 77%. 64w x .77 = 49.28w and going by this base for new pvs i am only off by 4.48w from a new pv. basing it on 49.28w and multiplying by .7 for the years of degradation would put it at 34.496w and that obviously isn't the case.

    you guys figure it out, but it gives an idea that amorphous is not worth it in the overall scheme of things unless the advantage is for a higher breakage resistance like my us64s have. i know for a fact that rocks have been hurled at them and i can't rule out adults did it.
  • brandywinebrandywine Registered Users Posts: 15
    Re: Using bare panels

    http://www.youtube.com/watch?v=6ggHr9f3FXA
    first of 5
    Posted our video about how to attach junction boxes to laminates we bought from Sunelec.

    Mickie & Travis
  • RCinFLARCinFLA Solar Expert Posts: 1,280 ✭✭✭
    Re: Using bare panels

    If you have a digital camera take a picture and 'go advanced' to post it here. You might have to down sample picture a bit to keep to forum's maximum jpg file size. Looking for number of cells in the panel. For 55 watt panel you might have half cells.

    You can start by measuring open circuit voltage and short circuit current in full noon sunlight. With a DVM, for short circuit current just put DVM on 10 amp scale, move red test lead to "10 amp" input and put directly across panel + lead to positive voltage on panel.
  • cruiser guycruiser guy Solar Expert Posts: 87 ✭✭✭✭
    Re: Using bare panels

    Finally back to these bare panels. This is a copy of the typical printout for these bare panels. I realize they are likely not compatible with anything currently out there. I have six of these. I also got the junction box/connectors for them.

    What is the best configuration to use these in?
    What can I expect in an energy harvest from these (located in Sierra Leone, about 7 degrees north of the equator and in a place with full sun when the sun shines)?
    Can I hook these up without a charge controller or do I still need a charge controller?
    Would it be unwise to try to provide an inverter off these as well as charging batteries for night use?

    I'd like to use these to provide power for a system of 12vDC LED lights in a children's home. I am told a few hours of light each day maximum. I'm contemplating using a 12v relay off the panel infeed to power an N.O. relay for the inverter so the inverter is only operational during periods of sun.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Using bare panels

    Reading the numbers ...

    Isc 9.06, Voc 7.0, Vmp 5.52, Imp 8.445

    You will need to put at least three in series to get a high enough Vmp for a 12 Volt system (16.56) and that will be pretty low (high temps dropping Voltage, V-loss through wires).
    Since you have six panels, your best bet is all six in series for a string @ Vmp 33.12 Imp 8.445 and use an MPPT controller to down-convert for a 12 Volt system.
    Technically the Wattage is too high for the Morningstar 15 MPPT so you'd need a Rogue 3024 (temporarily discontinued pending new model) or something like it. Beware the Blue Sky 2512 can not take the high input Voltage.

    Kind of a mess, really.
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Using bare panels
    mike90045 wrote: »

    Amorphous is ... supposed to produce a little better in less than full sun.

    Striving for clarity here: As I understand it, amorphous is supposed to be better (by some unspecified factor) in indirect sunlight or diffuse sunlight. That is, when haze or clouds are diffusing the sunlight so that it comes more uniformly from all directions rather than in a straight line from the visible sun. (There may also be some better performance in direct sunlight which is well off the axis of the panel.)
    A quantitative test for this is whether you see dark, sharp-edged shadows or not.

    To some people "less than full sun" may have other meanings, such as blotchy shade, as from a sparse set of leaves and branches. (Amorphous panels are also reported to be better under those conditions, but that is a separate effect from the first one.)
    SMA SB 3000, old BP panels.
  • cruiser guycruiser guy Solar Expert Posts: 87 ✭✭✭✭
    Re: Using bare panels
    Kind of a mess, really.

    Is the implied suggestion, "Don't bother"?

    For this application the likelyhood of future expansion is small. There are no "mission critical" items on line in this building and the occupants are used to not having power so when lights go out it will not present the same inconvenience as it might to you or I.

    It is more of a means of giving light to the children living in the home to study in the evening prior to going to bed. As it is now the children crowd around a small solar powered portable LED lantern.

    For a charge controller how does the Blue Sky 1524iX look? It should handle the watts and voltage if I am reading the specs right.
    Can the load contacts be used to power 12vDC LED lights so the battery cannot be discharged too deeply?
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Using bare panels
    inetdog wrote: »
    Striving for clarity here: As I understand it, amorphous is supposed to be better (by some unspecified factor) in indirect sunlight or diffuse sunlight. That is, when haze or clouds are diffusing the sunlight so that it comes more uniformly from all directions rather than in a straight line from the visible sun. (There may also be some better performance in direct sunlight which is well off the axis of the panel.)
    A quantitative test for this is whether you see dark, sharp-edged shadows or not.

    To some people "less than full sun" may have other meanings, such as blotchy shade, as from a sparse set of leaves and branches. (Amorphous panels are also reported to be better under those conditions, but that is a separate effect from the first one.)

    I think we clarified this in another thread: http://forum.solar-electric.com/showthread.php?14646-Amorphous-vs-Crystalline-in-Low-Sun-Areas/page3
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Using bare panels
    Is the implied suggestion, "Don't bother"?

    For this application the likelyhood of future expansion is small. There are no "mission critical" items on line in this building and the occupants are used to not having power so when lights go out it will not present the same inconvenience as it might to you or I.

    It is more of a means of giving light to the children living in the home to study in the evening prior to going to bed. As it is now the children crowd around a small solar powered portable LED lantern.

    For a charge controller how does the Blue Sky 1524iX look? It should handle the watts and voltage if I am reading the specs right.
    Can the load contacts be used to power 12vDC LED lights so the battery cannot be discharged too deeply?

    No; you're going to have difficulty finding a charge controller that will meet the specs. It has to be MPPT type and it has to be able to take the maximum input Voltage of Voc * all six panels (42+ Volts). The 1524IX has a maximum input of 45.6 for Voc (I just looked that one up). One snap of cold weather will exceed that. Otherwise it looks like that would work.

    Another option would be to use only four panels on a MS 15 MPPT. That would reduce the amount of battery capacity you could support to about 100 Amp hours to 200 Amp hours depending on whether you can keep loads off during charge time (10% rate to 5% rate). You might even be able to sneak a fifth panel in series on that controller if the temps are high and thus the panel Voltage kept low.

    As a rule, the LOAD contacts on these small controllers are meant for DC loads up to the rating of the charge controller. The 1524 is good for 20 Amps on a 12 Volt system, so as long as the LED total did not exceed that it would work.
  • cruiser guycruiser guy Solar Expert Posts: 87 ✭✭✭✭
    Re: Using bare panels
    No; you're going to have difficulty finding a charge controller that will meet the specs. It has to be MPPT type and it has to be able to take the maximum input Voltage of Voc * all six panels (42+ Volts). The 1524IX has a maximum input of 45.6 for Voc (I just looked that one up). One snap of cold weather will exceed that. Otherwise it looks like that would work.

    As a rule, the LOAD contacts on these small controllers are meant for DC loads up to the rating of the charge controller. The 1524 is good for 20 Amps on a 12 Volt system, so as long as the LED total did not exceed that it would work.

    What is defined as "cold weather"? Here in Sierra Leone the lowest recorded minimum temperature in the capital Freetown is 19 deg C.

    Am I right that these panels when all six are connected in series can be expected to produce 42 Voc (7 Voc x 6 panels) at standard conditions? Reading the technical bulletin from BlueSky (bulletin #100214) it appears that if the panel output at standard conditions is less than the recommended maximum Voc of the charge controller at standard conditions all should be fine. The Blue Sky spec sheet on the 1524iX shows a maximum input voltage of 57v and a Voc of 45.6 as you state. They talk about a possibility of the volts exceeding the Voc by up to 25% thus the 57v maximum but comparing Voc to Voc it should all be fine. These will be installed about 12" off a corrugated sheet metal roof. Am I reading this technical bulletin right? Correct me if I'm wrong please.

    How do Imp and Isc compare? I assume Isc is short circuit amps but what us Imp stand for? The technical bulletin talks about an Imp minimum to adequately charge batteries and an Isc maximum for the controller but it doesn't tell how to correlate Imp and Isc. Is the Isc 9.06 amps on these panels (not sure what the asterix means)? If so then at a nominal 24v I will exceed the power input to this charge controller.

    How about the BlueSky 3024iL charge controller? It will handle the same voltage but a higher amperage than the 1524iX.

    20 amps at 12v is 240 watts. How many 12vDC LED lights can that be expected to power? The LED lamps in my house are 2 watt each on 230vAC. The lights in the children's home will be 12vDC (no wattage noted on the 12vDC lamps). If wattage is roughly the same between the DC and AC lamps then I should be able to connect 120 12vDC LED lamps!! In reality I expect not more than 10-12 lamps total in the house.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Using bare panels

    At 19C for a lowest temperature you should be fine. Where I am that isn't even the high today, or for much of the year!

    Looks like that Blue Sky 1524iX will work in this situation.

    Imp is the current at maximum power. Isc is the short circuit current. A panel's maximum power is Imp * Vmp. You will not see Isc on a panel in operation. Often you won't see Imp either.
    I think you (or they) have them confused with Vmp and Voc, as usually you need sufficient Vmp to be able to charge batteries (it must be higher than battery Voltage) and Voc can not exceed the controller's maximum input Voltage.

    What you should get with all six panels in series is an array with these specs: Voc 42, Vmp 33.12, Imp 8.445, Isc 9.06, total Watts 279.9 max.
    The output from the controller should be approximately (279.9 * 0.77 typical efficiency /12 Volts) 18 Amps peak. This is close to the 1524's 20 Amp maximum for 12 Volts, but chances are you will not see that much due to high temps lowering panel Voltage at the time of maximum insolation. As a result, I don't think the 3024iL offers any advantage.
    20 amps at 12v is 240 watts. How many 12vDC LED lights can that be expected to power? The LED lamps in my house are 2 watt each on 230vAC. The lights in the children's home will be 12vDC (no wattage noted on the 12vDC lamps). If wattage is roughly the same between the DC and AC lamps then I should be able to connect 120 12vDC LED lamps!! In reality I expect not more than 10-12 lamps total in the house.

    Watts are Watts, basically. So in theory 240 Watts from the charge controller (it will be pulling power from the batteries to meet that current even under full sun) is one hundred twenty 2 Watt LED's. EXCEPT that if your LED's are 230 VAC, and therefore require an inverter to be powered. This means you need to account for the inverter's consumption as well, and you should not wire an inverter to a charge controller's LOAD terminals. So in that case it's a different set of calculations.

    But the ones you will be installing here are 12 VDC, right? So now you need to know either their current or Wattage to get an approximate idea of how much power they will consume. You can't do it on a basis of Voltage alone. Just because the lights you have are 2 Watt does not mean these will be also.
  • cruiser guycruiser guy Solar Expert Posts: 87 ✭✭✭✭
    Re: Using bare panels
    What you should get with all six panels in series is an array with these specs: Voc 42, Vmp 33.12, Imp 8.445, Isc 9.06, total Watts 279.9 max.
    The output from the controller should be approximately (279.9 * 0.77 typical efficiency /12 Volts) 18 Amps peak. This is close to the 1524's 20 Amp maximum for 12 Volts, but chances are you will not see that much due to high temps lowering panel Voltage at the time of maximum insolation. As a result, I don't think the 3024iL offers any advantage.

    But the ones you will be installing here are 12 VDC, right? So now you need to know either their current or Wattage to get an approximate idea of how much power they will consume. You can't do it on a basis of Voltage alone. Just because the lights you have are 2 Watt does not mean these will be also.

    Looking further at the specs on the 1524iX the maximum current is only 15 amps if the PV voltage is excess of 12v nominal so I guess the 1524 is too small.

    In this instance we will be using 12vDC lights direct from the battery and through the charge controllers "Load" terminals if the amperage is within the maximum allowed. I measured the amperage from one of the LED lights when connected to a 12vDC source and the largest one shows 0.3 amps maximum (tough to know exact as it is so low it gets into the accuracy error of the meter) but assuming it is accurate I could have in excess of 60 of these 12vDC LED lights before I hit the 20 amp threshold possible with all lights on. I don't expect anything close to that many lights. Do 12vDC LED lights have any kind of "inrush" current which needs to be considered in this case? I can see that the lighting controller may well end up being the "light switch" for the whole building over time and if there is an inrush current if all lights are left on I'd need to take that into account.

    Has anyone used the lighting control in conjunction with the load control of the Blue Sky charge controllers? I realize that I would need the ProRemote as a programming tool in addition to the charge controller. I'm trying to create a system that can somewhat protect itself from excess discharge. Here in Sierra Leone many people like to leave the light on all night to "ward off evil spirits" but of course this can take down the batteries in short order. I like the idea of the load control and lighting control to provide a reasonable amount of light after dark, say 3-4 hours, while protecting the battery from excessive discharge. Here in Sierra Leone so close to the equator the daylight and nighttime does not change significantly as it does up north. Here dawn is about 6:30AM and dusk is about 6:30-7:00PM year round.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Using bare panels

    I have to say Blue Sky controllers aren't the best. Their confusing specifications and operation being one of the key reasons. But yes it does say if battery or PV Voltage is over 12 nominal the output is limited to 15 Amps max. What good is that?

    I haven't used Blue Sky for this purpose, only Morningstar. Unfortunately their MPPT controller has the same 15 Amp maximum out. It can take up to 75 Voc. If the LED's are only 0.3 Amps you should be able to handle quite a few on 15 Amps. Unlike some of their PWM versions, however, it does not have the ability to switch lights on when the PV goes dark.

    You can see this design would be much easier if it weren't for those odd ball panels. :roll:
  • cruiser guycruiser guy Solar Expert Posts: 87 ✭✭✭✭
    Re: Using bare panels

    It would be easier with standard panels but the price is right with these ones!!

    Besides, shouldn't we always be up for a challenge?
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Using bare panels
    It would be easier with standard panels but the price is right with these ones!!

    Unless you end up spending even more money just to get them to work.
    Besides, shouldn't we always be up for a challenge?

    Not at my age. :p
  • PhotowhitPhotowhit Solar Expert Posts: 4,879 ✭✭✭✭
    Re: Using bare panels

    As I recall amorphious panels are better in the heat than regular mono or poly panels(their only redeeming feature), so you might be fine using a standard PWM charge controller and strings of 3. So long as the blue sky just clips the output you should be fine, as it will be rare to meet the standards at which it might put out more than 15 amps, it uses some energy and only when your batteries are very low do you charge below 14V (we recomend staying in the top 20%) so you wouldn't loose much, 14vx15amps = 210 watts or about 75% of panel rating, it's rare to see much more than 85% of panel rating and the CC will eat some of that.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • cruiser guycruiser guy Solar Expert Posts: 87 ✭✭✭✭
    Re: Using bare panels

    OK, here are some photos of the business side and backside of these panels and the function box we have to run them with. Now, how exactly do I get this all together? I'm going to do some volt readings tomorrow in the afternoon with hopefully full sun. What kind of panels are these?

    Where do I get the ribbon to take the leads from one end to the other so all leads are at the same place? Do I even need to? I assume I need to cover these leads and where they exit the panel to make it weather tight as well?

    On the ribbons, one end is noted as positive with 8.6 stamped beside it. The other end has no markings of any kind.

    We're going to build a steel framework to hold these all together.

    Attachment not found.Attachment not found.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Using bare panels

    Oh no. The junction boxes aren't even attached to the panels? How much did they pay you to haul these things away?

    Junction box: negative is on the left, positive is on the right in the picture. It has three sets of bypass diodes; looks like it was designed for a 3 segment panel.

    Panels. What are they? Good question. Put some light on them and poke at the connections with a DVM. The one labeled 'positive' probably is, the other one likely negative, and what looks like a connections at the opposite end the junction between two segments perhaps? In other words it doesn't look to me like those junction boxes were meant to go with those panels.

    Work it out and diagram V+ and V- at Voltages in respect to the combinations available. If they are two segment panels with (+) at one end and (-) at the other it will be difficult to connect them up (unless each segment has sufficient Voltage to be used as-is in which case you parallel them).

    One other thing: got aspirin? :roll:
  • cruiser guycruiser guy Solar Expert Posts: 87 ✭✭✭✭
    Re: Using bare panels

    OK, I put one of these out in the sun today. The end labeled positive is in fact positive. Both of these leads have 0 potential between them but 6.45vDC with either of the leads at the other end, which we now know are negative. There is also no potential between either of the negative leads.

    Anything else to check with regards to figuring out how to connect these?

    Do I assume that I need only one lead from each end? Seems odd as manufacturers will use as little material as possible and would not use two leads if one will do. If they were separate sections of panel then I would have assumed I'd get voltage potential between only two leads and not three much like having two batteries disconnected beside each other..

    How do these connect to the junction box or can they? I have no instructions with the junction boxes.

    I was going to use the ribbon that used to be put on glass for security alarm purposes to bring the leads from one end of the panel back to the other end so all leads are adjacent to each other.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Using bare panels
    OK, I put one of these out in the sun today. The end labeled positive is in fact positive. Both of these leads have 0 potential between them but 6.45vDC with either of the leads at the other end, which we now know are negative. There is also no potential between either of the negative leads.

    Anything else to check with regards to figuring out how to connect these?

    Do I assume that I need only one lead from each end? Seems odd as manufacturers will use as little material as possible and would not use two leads if one will do. If they were separate sections of panel then I would have assumed I'd get voltage potential between only two leads and not three much like having two batteries disconnected beside each other..

    How do these connect to the junction box or can they? I have no instructions with the junction boxes.

    I was going to use the ribbon that used to be put on glass for security alarm purposes to bring the leads from one end of the panel back to the other end so all leads are adjacent to each other.

    Well urk! 6.45 Volts isn't much at all. You could wire the two halves in series and get 13.90 Volts, which also isn't much at all. With no load on them they should be putting out Voc which ought to be around 17 Volts for a "12 Volt" panel (8.5 Volts per half - this fits with the 8.6 stamping). The series wiring will require connections across from one (+) to the other (-). You could also wire the individual panel halves in parallel, then put two or more panels in series. Neither is ideal given the Voltage and physical layout of the panels.

    Next thing to do if you can is test each half of one panel for short circuit current. You need bright sun directly on the panel and an Ammeter capable of reading the expected current connected from (+) to (-) on one half. These are supposed to be 50 to 60 Watts? That should be under 4 Amps current.

    I don't think those junction boxes are going to be of much use for connecting these panels; the physical layout of the two things is quite different.
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