Problem with Kyocera 120 Panel

Today I had the panel in full sun. Took off the blocking diodes. Measurement at + and - terminals with meter. 19.18 volts.
Then I attached the panel to a battery which I know is good. Ran for 7 hours.
Starting voltage of battery 12.28 volts. Ending voltage of battery. 12.28 volts.
Yesterday attached same panel to Prostar 30 controller. Did same with another panel of same size and same amount of light. Prostar showed no incoming amperage for problem panel.

Thus the lack of charge of the battery and yesterday's reading on the Prostar tells me that I have voltage but no amperage.
Very strange. Any other ideas?

Comments

  • nielniel Solar Expert Posts: 10,311 ✭✭✭✭
    Re: Problem with Kyocera 120 Panel

    sounds like it could be a bad pv with a possible bad internal connection. the open circuit voltage of the 120 should be somewhere around 21v and not 19v. years ago i believe they had a slew of bad connects and you may have gotten one of those old pvs. send it back if you can.
  • BB.BB. Super Moderators, Administrators Posts: 29,518 admin
    Re: Problem with Kyocera 120 Panel

    The other thing you should be able to try with a single solar panel is to short the output with your DVM / amp meter... In full sun, with the panel "shorted" by the current meter, you should get close to the rated output current. You will not hurt the panel by shorting it with the meter. (make sure the meter can handle the rated current--and is not just a remote reading meter for a current shunt or you will destroy the meter).

    If, as Niel suspects, there is an open circuit, there won't be anywhere near rated amperage coming out of the panel... A standard DVM (digital volt meter) takes so little current that even a very high resistance connection (in the 10-100,000 ohm range) will still give a near normal open circuit voltage reading. You need to measure the panel under load.

    You could also put some other load out there (12 volt light or power resistor that can handle the rated power (voltage and current) and measure the current too.
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • nielniel Solar Expert Posts: 10,311 ✭✭✭✭
    Re: Problem with Kyocera 120 Panel

    bb,
    it would not be an open circuit or you would not get a voltage reading. i'm figuring on a bad (highly resistive) internal connection. it is also possible for a cell or two to be bad, but what are the odds on that even though possible. having a bad connection or even a bad cell or two would be very similar to a severe shading without bypass diodes.
    i don't want to make it sound like you're (johnspan) dumb or anything, but did you aim the correct side at the sun with no shadows on the pv? i have to ask as i don't know you or saw the circumstances and it's wrong for me to assume anything. i also think bb's recommendation to measure its short circuit current is a good one as it would confirm the pv's condition, but as also stated be very carefull that your meter can take it and you must do it correctly or risk blowing the meter.
  • BB.BB. Super Moderators, Administrators Posts: 29,518 admin
    Re: Problem with Kyocera 120 Panel

    Niel,

    Open circuit in the sense that there may be a high resistance connection (in the 10,000-100,000 Ohm range) that would still read near normal voltage (resistor divider circuit) with a DVM.

    Assuming the panel is:

    Module: Kyocera KC120-1
    Max Power Voltage - Vmp 16.9 Vdc
    Open Circuit Voltage - Voc 21.5 Vdc
    Voltage Temp Coeff - Vtoc -0.0824 V/°C
    STC Rating - Pmp 120 Wstcdc
    Max Power Current - Imp 7.1 Adc
    PTC Rating 105.7 Wptc

    Then it is possible the 19.18 vdc open circuit voltage reflects a panel surface temperature of ~120F... In any case, the short circuit current test will show if the panel is more or less electrically sound. It is also possible that the meter is in need of a bit of calibration.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • System2System2 Posts: 6,290 admin
    Re: Problem with Kyocera 120 Panel

    Gurus, thank you for your quick input. The vendor reports that he has had a lot of returns with the same panel. Will try your recommendations, however Yes, the panel was in full sun. Ambient temperature was about 90 F.
    John
  • System2System2 Posts: 6,290 admin
    Re: Problem with Kyocera 120 Panel

    i had a similar problem with my 120 panel.. it was putting out fine i just got low amp reading with my meter... way low ( 3 and 4 amps)
    and 19.6 volts in full sun. come to find out i had a bad meter. a friend came over with his and read 19.8 volts and 7 amps under load and 5 amps load with meter only. would be nice to find out what the build date of the bad panels so i could check mine.. never know. all mine were built 2001 , also is that why they stopped making the kc-120's ?
  • JamesJames Solar Expert Posts: 246 ✭✭
    Re: Problem with Kyocera 120 Panel

    Hello ChadJones99,

    The questionable panels are from late 1999 thru 2001.
    Kyocera has been great regarding the replacement. They are replacing all 16 of my panels, even though only 12 were had those date codes. I would highly recommend that you contact Kyocera.
    They will ask for the date codes/serial numbers from all you KC120 units.
    The waiting time is about 30 days. Mine will be here in a few days.  :-)

    By the way folks, They are sending me KC130's, so I get a small bonus for my trouble.

    Kyocera warranty contact:
    [email protected]
  • System2System2 Posts: 6,290 admin
    Re: Problem with Kyocera 120 Panel

    do you have to be the orignal owner ? i bought 3 racks of 4 120 kc-120 that are 2001 year built
    also whos pays for shipping ?
  • JamesJames Solar Expert Posts: 246 ✭✭
    Re: Problem with Kyocera 120 Panel

    The warrenty states original purchaser, but I would try to avoid telling them that you are not the original purchaser. Do you know where the original owner purchased them?
    Kyocera knows what dealer got them due to the seiral #'s.
    If you knew what dealer, you could just say they came from ".......* dealer.
    I really don't think they will hassle you on it due to the widespead problem they had with these units...but thats just my opinion...again, I would not bring it up at all if you can avoid it.

    They pay shipping both ways. You will send yours back to them in the same boxes the replacements came in. They will provide prepaid shipping lables. Mine are coming via FedEx Freight.

    Good luck, hope it works out for you.
    j
  • JamesJames Solar Expert Posts: 246 ✭✭
    Re: Problem with Kyocera 120 Panel

    Chad, did you by chance just buy these used off ebay?
    I saw racks of 4 kc120's on ebay recently by two different sellers. Neither seller would give me date codes, so i passed. One seller tried to sell me a rack of 4 with shipping for $1000.00 as an off ebay deal. , but like I said, he would not give me date codes so I passed on the deal. They may have been fine, but not knowing if Kyocera would honor a warranty, well...

    I was just curious
    j
  • System2System2 Posts: 6,290 admin
    Re: Problem with Kyocera 120 Panel

    I did get them off of EBAY about 6 months ago maybe 4 months ago.. but anyway I just now got around to trying to install some of them.. 1k for 4 that's a smoking deal. I would stay away if I could not come test them and haul them my self. I paid about 1500 per rack..( shipping was not a option) I went to CALIFORNIA to the guys house he had a lot of them ( 20+ racks) I picked throw them and got the best looking ones .. I volt tested them in the sun ( 78 volts in a series )( 4 to a rack)there and NOT knowing allot about solar I called a friend when I was there that knows a lot about it . he said voltage I gave him sounded good and I did not amp test them like I should have. anyway my friend did not know about the 120 problem ether . but I don't know if these are bad. just want to check, being I got a good deal . there is usually a reason for that type of deal. Like I said I had a bad meter . using his meter the other day I think these are good ones. my build date on my panels are 2001.5
    I email the person you post on your post
  • System2System2 Posts: 6,290 admin
    Re: Problem with Kyocera 120 Panel

    here is a ebay link to what i bought.. this is not me but another WINNER i could not get the link for mine as it is to old
    http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=110010888936
    now the bad kc-120's what was wrong with them were they just alittle week or something else ? because if anything mine might be a little week , but do look like there working.
  • mike95490mike95490 Solar Expert Posts: 8,380 ✭✭✭✭✭
    Re: Problem with Kyocera 120 Panel
    James wrote:
    The questionable panels are from late 1999 thru 2001.
    Kyocera has been great regarding the replacement. They are replacing all 16 of my panels, even though only 12 were had those date codes.

    Anyone have any close up photos of the bad spots on the panels ? I'm wondering if some new Sharp 208W (spring-2006) I got have the same problems. If so - could you email to me @ solarATnaturalstudies.org ?
    Mike

    [edit] What I've got is a silver dollar size brown spot on the PV cell behind the glass, at a corner of the panel. I guess it's not the main power contact, but it still looks ugly. Next time I go up, I will have a camera, scale and color wheel.
    photos posted here
    http://www.wind-sun.com/smf/index.php?topic=1920.0
    White backing sheet looks unharmed, and can feel no bump or pinhole
    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 ,

  • JamesJames Solar Expert Posts: 246 ✭✭
    Re: Problem with Kyocera 120 Panel

    Hey Mike, I have no photos as my panels sitting in the boxes for several years, therefore they have not had much use.

    I will share an excerpt from a email from Kyocera...

    .........."The whole problem with the KC120 failure is that just because they test okay now, doesn’t mean they will a year from now. What happens is when the panel heats up the solder joint at the top of the panel pulls apart and creates an open circuit. If the panels are not used or are not in direct sun light on a regular basis it may take longer for the failure to occur. This is not in ALL KC120 modules but the problem is decent sized so to speak. "

    Another forum I visit spoke of brown "burn" spots on the rear side of panels through the white backer plastic
  • System2System2 Posts: 6,290 admin
    Re: Problem with Kyocera 120 Panel

    I just got a email from Kyocera, with all my data , I tested them all today, and they did not look that bad. anyway gave them S/N , and test data. they sent me a RMA via email ! hee haa
    sure am glade to finaly deal with a company that stands behind there product. not very often that happens !
    Chad
  • JamesJames Solar Expert Posts: 246 ✭✭
    Re: Problem with Kyocera 120 Panel

    Thats great news Chad!
    Did they ask for info on where you bought them?
  • System2System2 Posts: 6,290 admin
    Re: Problem with Kyocera 120 Panel

    No, not yet. they just ask if I got them from original dealer or other .. I put other then put install dealer. which is what the guy I bought them from said. that he had a install company a few years ago and this was left over stock. I don't know if he was telling me the truth are not.
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