Seeking help figuring out j box configuration.

littleharbor2littleharbor2 Solar Expert Posts: 1,599 ✭✭✭✭

So I bought an old grid tie system that is composed of 66 Seimens SP75 panels and a Trace SW 5548 inverter with large capacitors insted of batteries. This system will be broken down to individual panels and sold piece by piece. As I'm breaking down the tri-lam , 3 panel modules and getting into the junction boxes I find these panels have been set up in the 6 volt configuratuon. These panels could be wired as 6 or 12 volt nominal. In the junction box there is some sort of electrical component on one of the two + output terminals, bottom left, connecting to one of the two - negative terminals. I have removed it and it can be seen in the top photo of the J box connections. Not sure what it is but maybe a blocking diode.

So my dilema is I cant figure out how to get 12 volt nominal voltage from these panels. I have handled hundreds of these panels in the past and haven't had any issue configuring them for 12 volt output. In the bottom photo I have already set the jumpers for 12 volt. The factory configuration would have bypass diodes on the right and left where I have a solid wire jumper. I can't see the fact that I have solid wire in place of diodes would prevent the panels from making voltage but wired as the lower photo I'm getting 0 volts even from the Buss tabbing coming in from the cells. It's a mystery.

Has anybody out there ever seen this Jbox configuration and can possidly point me in the right direction?.



2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 540 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

Comments

  • EstragonEstragon Registered Users Posts: 4,494 ✭✭✭✭✭

    If I'm reading this right, the 4 outermost terminals on the bottom row are + and - outputs (2 for + and 2 for -). If so, why is there a wire connecting terminals #2 and #6? Wouldn't that be shorting the output?

    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • littleharbor2littleharbor2 Solar Expert Posts: 1,599 ✭✭✭✭

    The #2 terminal has/had the device laying on the top of the J box page I included. Not sure what it is though. Possibly a blocking diode? Not sure. I tried getting voltage with and without it, no go.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 540 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • TecnodaveTecnodave Registered Users Posts: 418 ✭✭✭✭

    Just looking, I think that is a zener diode which will clamp the voltage no higher than the zener voltage, strange! Protect the inverter input from voltage rising too far!

    2 Classic 150, 2 Kid, 5 arrays 7.5 kw total  2ea.  2S6P Sharp NE-170/NE-165, 1ea. 12P Sanyo HIT 200,  2ea. 4/6P Sanyo HIT 200, MagnaSine MS4024AE, Exeltech XP-1100,  2 Banks L-16 battery, Rolls-Surette S-530 and Interstate Traction, Shunts with whizbangJr and Bogart Tri-Metric, iCharger i208B  dc-dc buck/boost converter with BMS for small form lithium 8S 16650 or LiFePO4,
  • TecnodaveTecnodave Registered Users Posts: 418 ✭✭✭✭

    Looking once again, your wiring is not correct! The two outer jumpers need to be removed. Those two diodes that were there are cell bypass diodes used to bypass power around a shaded panel. They are not needed unless you have shading issues. It hurts nothing to leave them in place as they do nothing in a full sun situation.

    i have one of those panels with the Solarix name on it, same 6 volt 12 volt setup.

    You have some antique panels there. Probably not worth much.....but enough power for a camper van or like application. I was given mine.....its in the oldies row for show..

    2 Classic 150, 2 Kid, 5 arrays 7.5 kw total  2ea.  2S6P Sharp NE-170/NE-165, 1ea. 12P Sanyo HIT 200,  2ea. 4/6P Sanyo HIT 200, MagnaSine MS4024AE, Exeltech XP-1100,  2 Banks L-16 battery, Rolls-Surette S-530 and Interstate Traction, Shunts with whizbangJr and Bogart Tri-Metric, iCharger i208B  dc-dc buck/boost converter with BMS for small form lithium 8S 16650 or LiFePO4,
  • littleharbor2littleharbor2 Solar Expert Posts: 1,599 ✭✭✭✭
    edited April 2019 #6

    Thanks for your input Dave. I will try to change up the jumpers. As mentioned this was a grid interactive setup with a 90's era Trace inverter and, apparently, 2 large capacitors for the "Battery".

    I have a niche market for these old 12 volt panels. Have sold literally hundreds of them. They're not the antiques, Here's some if the real antiques I've collected. I have others as old, or older. The second, shorter one is a one off panel made with cells intended for Satellite use.


    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 540 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • TecnodaveTecnodave Registered Users Posts: 418 ✭✭✭✭

    that second panel is rare indeed. I have never seen anything like that. It might be a gallium arsenide panel. Silicon photovoltaics do not stand up to the space environment. Gallium Arsenide with concentrators were commonly used in early communication satellites.

    2 Classic 150, 2 Kid, 5 arrays 7.5 kw total  2ea.  2S6P Sharp NE-170/NE-165, 1ea. 12P Sanyo HIT 200,  2ea. 4/6P Sanyo HIT 200, MagnaSine MS4024AE, Exeltech XP-1100,  2 Banks L-16 battery, Rolls-Surette S-530 and Interstate Traction, Shunts with whizbangJr and Bogart Tri-Metric, iCharger i208B  dc-dc buck/boost converter with BMS for small form lithium 8S 16650 or LiFePO4,
  • TecnodaveTecnodave Registered Users Posts: 418 ✭✭✭✭

    I also sell low power panels for people surviving in camper van situations. I have hundreds of Seimens SM-55 panels sold at government auction for a few bucks each. Arco/Seimens had huge contracts with State of California to provide these for freeway call boxes and lighted street signs. I am getting 60 to 70 cents a watt for these. The cheap panels are all grid tie panels which are hard to use in a 12 volt setup on the cheap. I have even traded 60 cell new grid tie panels for these "12 volt" panels to ease new users who on bad advice bought the wrong panel for the situation.

    2 Classic 150, 2 Kid, 5 arrays 7.5 kw total  2ea.  2S6P Sharp NE-170/NE-165, 1ea. 12P Sanyo HIT 200,  2ea. 4/6P Sanyo HIT 200, MagnaSine MS4024AE, Exeltech XP-1100,  2 Banks L-16 battery, Rolls-Surette S-530 and Interstate Traction, Shunts with whizbangJr and Bogart Tri-Metric, iCharger i208B  dc-dc buck/boost converter with BMS for small form lithium 8S 16650 or LiFePO4,
  • littleharbor2littleharbor2 Solar Expert Posts: 1,599 ✭✭✭✭

    The cells do seem to be composed of something other than silicon. The radial traces are what intrigue me. Pretty sophisticated for old tech. I came across an obsolete listing one time online Showing these cells for sale which described them and said they, at one time sold for $100.00 a piece.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 540 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • littleharbor2littleharbor2 Solar Expert Posts: 1,599 ✭✭✭✭


    I totally get it. They are quite popular with the RV/ sailboat crowd. The small footprint is one of the things that people are looking for.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 540 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • TecnodaveTecnodave Registered Users Posts: 418 ✭✭✭✭

    In days gone by I did two way radio, VHF and UHF repeaters on mountain tops. I remember the company buying solar panels at $900 each for small panels. We had one site up a mountain at 8800 feet or so that would get a lot of snow in the winter, making diesel fuel for the generators very expensive to deliver by snowmobile. The panels were less expensive than diesel snowmobiled 15-20 miles up a snowed in road......that was in the late '60's or very early 70's. solar has come a long ways since then. I bailed out of communications not long after that due to health effects of working in close proximity to many FM two way radio repeaters. Computers were hatching and I sailed that ship for a while, before going into power management.

    2 Classic 150, 2 Kid, 5 arrays 7.5 kw total  2ea.  2S6P Sharp NE-170/NE-165, 1ea. 12P Sanyo HIT 200,  2ea. 4/6P Sanyo HIT 200, MagnaSine MS4024AE, Exeltech XP-1100,  2 Banks L-16 battery, Rolls-Surette S-530 and Interstate Traction, Shunts with whizbangJr and Bogart Tri-Metric, iCharger i208B  dc-dc buck/boost converter with BMS for small form lithium 8S 16650 or LiFePO4,
  • littleharbor2littleharbor2 Solar Expert Posts: 1,599 ✭✭✭✭

    Nice. Good old skool experience. You're showing your vintage with the dates you're giving.🙂

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 540 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • TecnodaveTecnodave Registered Users Posts: 418 ✭✭✭✭

    Yep, I gotta admit I am very old school, born in the backwoods of Alaska in the '40's. I've been an off gridder for a while, born into a ham radio family started tinkering radios before I was a teenager so had very good head start, I excelled in electronics and ended up being an engineer for GE in many divisions communications, medical, power management before stepping into my own business. Basically now I do failure analysis of systems for many others. Wanna quit but the economics are not there.....the problem with retiring.....watta you do...every TV I have ever seen has a "brightness control" but no matter where I set that it just don't get any brighter, it's the same old dumb $hit!

    2 Classic 150, 2 Kid, 5 arrays 7.5 kw total  2ea.  2S6P Sharp NE-170/NE-165, 1ea. 12P Sanyo HIT 200,  2ea. 4/6P Sanyo HIT 200, MagnaSine MS4024AE, Exeltech XP-1100,  2 Banks L-16 battery, Rolls-Surette S-530 and Interstate Traction, Shunts with whizbangJr and Bogart Tri-Metric, iCharger i208B  dc-dc buck/boost converter with BMS for small form lithium 8S 16650 or LiFePO4,
  • littleharbor2littleharbor2 Solar Expert Posts: 1,599 ✭✭✭✭

    Sounds like you've had an interesting life. Do what you love and you'll never work a day in your life, or something like that, I've heard them say. I was a carpenter all my life but ruined my back. 3 surgeries later I find myself retired. Having fun in Baja when I can get down there. Probably going Baja full time soon. We'll see what 2020 brings.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 540 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • PhotowhitPhotowhit Solar Expert Posts: 5,577 ✭✭✭✭✭

    I agree on removing the outside 2 wires (or replacing with diodes) Curious guys, the wire that appears to almost short out the panel across the bottom. What the heck is that for?

    Perhaps some sort of 'reverse fuse' making a connection in case of a lightning strike? Not sure what this terminal does; I assume you are getting some voltage readings, so it hasn't shorted out the panel.


    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • TecnodaveTecnodave Registered Users Posts: 418 ✭✭✭✭

    I will stand by my statement earlier in this thread....that is very likely a zener diode. It does nothing until the voltage across it raises to its breakdown then it shorts out (bypasses) the power. In the case of the panel you would want the panel to operate at its MPP but unloaded the panel will raise in voltage, sometimes higher than the batteries or circuit can withstand. The zener diode prevents the voltage from raising above its trip voltage. In the very early days of solar they were used to prevent the panel from overcharging the battery. In this case where the panels are in a series string feeding into a grid interactive inverter the zeners would be there to prevent the 8 panels in series from presenting a voltage higher than the inverter input rating..........Note that (each) of these panels were wired in parallel then the resulting voltage on each panel would be about 10.5 VOC and about 9 volts at VMP so the series string of 8 ea. "6 volt" panels would be about 84 VOC and about 72 VMP, way over a 48 volt inverters rating of 64-68 volts. One huge diode could be used on the whole array but with individual diodes only the panels exceeding the desired maximum voltage would shunt the power. This will take into account shading of some panels.

    2 Classic 150, 2 Kid, 5 arrays 7.5 kw total  2ea.  2S6P Sharp NE-170/NE-165, 1ea. 12P Sanyo HIT 200,  2ea. 4/6P Sanyo HIT 200, MagnaSine MS4024AE, Exeltech XP-1100,  2 Banks L-16 battery, Rolls-Surette S-530 and Interstate Traction, Shunts with whizbangJr and Bogart Tri-Metric, iCharger i208B  dc-dc buck/boost converter with BMS for small form lithium 8S 16650 or LiFePO4,
  • TecnodaveTecnodave Registered Users Posts: 418 ✭✭✭✭

    When I worked in communications we used a single 75 watt zener diode across the solar panel output to keep the batteries from overcharging. PWM haven't been invented yet and MPPT was light years away. There were only series and shunt regulators available and very expensive because it was very new technology. This was in the era 1967-1972 or so as I remember, it's been a while. I seem to remember about 6 repeater sites where we had solar panels, way up some mountain, way off the grid, out in the boonies, in BFE, etc.

    2 Classic 150, 2 Kid, 5 arrays 7.5 kw total  2ea.  2S6P Sharp NE-170/NE-165, 1ea. 12P Sanyo HIT 200,  2ea. 4/6P Sanyo HIT 200, MagnaSine MS4024AE, Exeltech XP-1100,  2 Banks L-16 battery, Rolls-Surette S-530 and Interstate Traction, Shunts with whizbangJr and Bogart Tri-Metric, iCharger i208B  dc-dc buck/boost converter with BMS for small form lithium 8S 16650 or LiFePO4,
  • PhotowhitPhotowhit Solar Expert Posts: 5,577 ✭✭✭✭✭

    @Tecnodave I'm impressed with your memory, I went over to Specialty Concepts website to see when they started making the PWM Mark series 4x7 charge controllers. I think my early one was from around 1980 as were the panels I bought from Al SImpler SImpler Solar Systems back in 2000. He has been around for a while perhaps back to the early to mid 70's. Perhaps they were some of the first ones. I still have it somewhere. Need to be sure to add it to my collection of old solar panels. Amazing with all the fly by night solar companies, both Specialty Concepts (just making 1 CC now it appears, old stock?) and Simpler Solar Systems are both still around.

    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • TecnodaveTecnodave Registered Users Posts: 418 ✭✭✭✭

    Photowit,

    I have lots of stuff stored up there, sometimes I scramble the little bits then go back and retread my post later for accuracy and find I really was swapping memory of one thing with another. I just did that at MidNite forum telling a user that a MNDC125 breaker would fit in the space for the MNDC175/250......it doesn't....I remembered breakout tabs.....there were not any on my MNDC15 breaker panel. I had machined a breaker adapter to fit. I think that comes with loving your work....I found long ago if you truly love your work, it's not work. If I do not like my work environment I bail and find something I'm truly interested in. I do electrical work for a living, I really enjoy it, especially the system failure that nobody can point a finger at. I'm venturing into the unknown again as I have reverse engineered Chinese electro-accupuncture devices and now have 2 Russian PEMF medical devices in repair that nobody outside of Russia have repaired AFAIK, it's a challenge to me. I didn't want to wait 6 months to have my DiaDENS PEMF device repaired. I bought a new one and took apart the old one to diagnose it. Found the problem with no idea of what the chips were! My ex told me that when I die the earthworms had better take a hike, I would be dIsecting them LOL

    2 Classic 150, 2 Kid, 5 arrays 7.5 kw total  2ea.  2S6P Sharp NE-170/NE-165, 1ea. 12P Sanyo HIT 200,  2ea. 4/6P Sanyo HIT 200, MagnaSine MS4024AE, Exeltech XP-1100,  2 Banks L-16 battery, Rolls-Surette S-530 and Interstate Traction, Shunts with whizbangJr and Bogart Tri-Metric, iCharger i208B  dc-dc buck/boost converter with BMS for small form lithium 8S 16650 or LiFePO4,
  • littleharbor2littleharbor2 Solar Expert Posts: 1,599 ✭✭✭✭
    edited April 2019 #20

    Dave, I'm so glad I posted this question here. I want to thank you for taking the time to analyze my situation and posting here.

    Your thoughts on this Zener Diode make total sense being, as I said, the system was battery less W/ a Trace 48 volt inverter. I had never seen anything like this before. As far as I can tell, though I may be wrong, it was a 6 module in series set up. 8.5 volts Vmp. x 6 =51, 10.5 Voc. x 6 = 63 .


    The Zener diode does have a few numbers on it if it would help I'll post them

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 540 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • TecnodaveTecnodave Registered Users Posts: 418 ✭✭✭✭

    @littleharbor2

    Your situation is a new one to me. I have never heard of a battery based inverter being powered this way, obviously done by someone technically oriented . As I said in very early solar installations the only controller was a big zener directly across the battery. A 15 volt Zener will conduct nothing until the battery charges up to 15 volts then it "shorts out" enough power to keep the battery from overcharging. I was born in the backwoods of Alaska into a ham radio family...........does that explain why I have such varied knowledge of electric. We didn't have "grid" power. I built all tube ham radios, dozens of Heathkits, Knight kits etc. Was fascinated when transistors were available, I could not wait to get my hands on those! When computers hatched into being I had very early "microprosser development kits" and built computer kits, all the parts in baggies and bare boards. Ever hear of a RCA Cosmac or an Intel Intellic , I have both! Very early breadboard computer development kits. I subscribed to EDN (Electronic Developer News) a must read in those days. Development kits were offered to all who asked. My first computer is an Imsai 8080, paddle switches in and lights in binary output, no disk drive, no floppy, no screen.........entry in bit binary!....readout in bit binary!......no saving program! It's been a looong road. I don't program anymore. Well maybe in high level language.

    I would be curious of the rating of those zeners. A bench variable voltage power supply will very quickly show the operating point of the Zener.

    2 Classic 150, 2 Kid, 5 arrays 7.5 kw total  2ea.  2S6P Sharp NE-170/NE-165, 1ea. 12P Sanyo HIT 200,  2ea. 4/6P Sanyo HIT 200, MagnaSine MS4024AE, Exeltech XP-1100,  2 Banks L-16 battery, Rolls-Surette S-530 and Interstate Traction, Shunts with whizbangJr and Bogart Tri-Metric, iCharger i208B  dc-dc buck/boost converter with BMS for small form lithium 8S 16650 or LiFePO4,
  • littleharbor2littleharbor2 Solar Expert Posts: 1,599 ✭✭✭✭

    Dave, I'm pretty sure Trace had their hands in on this system. I'm not anywhere near your technical expertise here but I'm going by what the owner told me. He was a solar contractor way back then. He told me Trace sent him the inverter I got from him as a back up. It was still in the wooden crate it had been shipped in. The inverter was mounted up in one of the Trace outdoor enclosures and had the large capacitors all mounted and connected. Basically plug and play. Interesting way to fool the inverter that there was a battery bank connected. Being in sell mode the inverter would be sending all power to the grid, and only the grid.

    As to your learning experience from the early days of computers, although most of the terms are French to me, it's clear why you have such a wide knowledge bank with all things electronic. Your ability to recall all this historical stuff is amazing. Many people would have lost 2/3 of that information to time.

    I don't have an electronics workbench but is there some way I could test this Zenner Diode with a 9 volt battery and a voltage meter? I will be removing 66 of these little items. I'd be happy to mail you one, or all you want, if you like.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 540 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • TecnodaveTecnodave Registered Users Posts: 418 ✭✭✭✭

    I need a flush mechanism......my first phone number was Broadway 78065! LOL! I'm running out of room in the attic! A variable voltage power supply with voltmeter and ammeter will quickly show the voltage, just bring the voltage up slowly, it will not conduct any energy until it hits the regulation point.

    2 Classic 150, 2 Kid, 5 arrays 7.5 kw total  2ea.  2S6P Sharp NE-170/NE-165, 1ea. 12P Sanyo HIT 200,  2ea. 4/6P Sanyo HIT 200, MagnaSine MS4024AE, Exeltech XP-1100,  2 Banks L-16 battery, Rolls-Surette S-530 and Interstate Traction, Shunts with whizbangJr and Bogart Tri-Metric, iCharger i208B  dc-dc buck/boost converter with BMS for small form lithium 8S 16650 or LiFePO4,
  • littleharbor2littleharbor2 Solar Expert Posts: 1,599 ✭✭✭✭

    While off topic, again, it is my thread so here goes. I've found another of these vintage panels with the gallium arsenide , satellite cells. With the MFG. info on this panel I was able to pull up some info about the cells.

    https://www.latimes.com/archives/la-xpm-1992-03-02-fi-2238-story.html


    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 540 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

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