Jump to content

Crossy

Global Moderator
  • Posts

    46,457
  • Joined

  • Last visited

  • Days Won

    2

Posts posted by Crossy

  1. Yup ^^^.

     

    It took me a few minutes to actually find it, but it does seem to work.

     

    Click on the 3 dots to the left of your username top right (not the ones far right of the chat window).

    Select "Skype Dial Pad" from the drop down. It only appears if you have active credit or a live subscription.

     

    Easy peasy, the destructions that came with the email are carp!

    • Agree 1
    • Thanks 1
  2. This is the voltage of one of the long strings on startup in the morning.

     

    You can see the MPPT trying to start as the voltage rises but with no power available, max voltage is about 424V then it actually manages to start making power and pulls the voltage down to 260-270V which is the max-power point at this time.

     

    It's this time of day where the greatest risk to the MPPT maximum input voltage occurs. This is a major issue for those in the "cooler" parts of the world as Voc rises by about 0.4% per degree C below 25C (where it is specified). Even in Thailand a chilly, 15C, morning would raise Voc by 4%.

     

    image.png.59fa8da591447e8e7330238dfad254dc.png

    • Like 1
  3. 34 minutes ago, ExpatOilWorker said:

    What is the highest Voc voltage on any of your strings?

    Do you keep the Vmp right under the 425 max?

     

    Panels are 340W, Voc = 46.3V, Vmp = 38.7V

     

    Longest strings (2) are 10 panels so Voc = 463V, inverter spec. is 500V max. In reality they never get anywhere near that even on a "cool" morning.

    Vmp of these strings is 387V, the MPPT range is 150-425 (max power is 300-425), but once again they tend to run well below that.

     

    Snapshot just now, nowhere near max power generation this late in the day, trees and house get in the way 😞 

     

    image.png.db9107ce1aee9add82bff758eed8c0c9.png

     

    • Like 1
  4. 12 minutes ago, ExpatOilWorker said:

    Lightning 🌩 strike directly to any of your equipment or nearby and the EMP cause the havoc?

    Did the fault happen Sunday and you just noticed it Monday?

    Having this kind of "Spanish" moment is what I fear the most of being an independent power generator. 

    At least with the grid, you know it is someone else's headache to fix it.

     

     

    Strike was a tree about 30m from the arrays. This is the closest strike we've had since 2012 when we took a direct hit to the house!

     

    We noticed the RS-485 issue straight away, but the upset MPPTs only made themselves felt on Monday coz it went dark on Sunday.

     

    Keeping a grid connection for backup is cheap insurance.

     

  5. Carrying on from the flash-n-bang on Sunday.

    Fear!!!

    Monday came around and it was obvious something was awry.

    The Master inverter was banging along at 4kW or so, but all three Slaves were doing very odd things with their MPPTs. They seemed to be constantly re-scanning, the impact on production was massive.

    I checked the wiring and voltages, and verified that the surge-arrestors hadn't triggered (took them out).

    A power cycle of the slaves and then the whole system yielded zero improvement.

    Terror!!!!

    Suddenly! All output went off!! The inverters were all running but were displaying "OFF".

    Looking at Solar Assistant showed that the Remote Switch option was set to OFF.

    Tried to change the state without success, other parameters changed but not that one!

    I'm facing a bricked system!!


    I actually put the Deye dongles back on and tried to turn the inverters on via Deye Cloud. No joy.

    In desperation I did a factory reset on the Master and got the beast to come to life in stand-alone mode.

    Happy. At least we were able to carry local load.

    Then.

    Turned on comms to the slaves, 30 seconds later, "clunk", the master goes to OFF.

    OK back to stand-alone.

    Factory reset the slaves and set their RS485 addresses.

    Relief!!!!!

    Set the master to parallel and held my breath.

    It didn't go off.

    Turned on the load breakers and everthing started working much to my relief.

    I had a very relieved beer!!

    Of course, Brain of Britain here hadn't made a backup of the system settings, so I'm still messing around getting it right again, and making a backup!

    Evidently something got corrupted in the slaves but exactly what I have no idea.

     

  6. We just had a major (but short) storm, heavy rain and very strong wind (there was apparently hail just up the road).

     

    Nothing solar or car port moved!!

     

    However.

     

    I was sitting at my computer when a tree about 20m away got hit!! Flipping great bang! Scared the willies out of me! I needed a beer :whistling:

     

    The inverters flipped to grid and reset but no damage and everything came back online after a minute or so.

     

    Meanwhile, my step-son who had been on the carport roof when the rain started decided that he wasn't going back up there today. I can't imagine why :whistling:

     

    EDIT Turns out we fried one of the RS485 to USB dongles that connect to the Pi. Had a spare in the bits box 🙂 

    • Haha 1
  7. 20 minutes ago, impulse said:

     

    My 2 cents.  Just because you don't have vermin today doesn't mean you never will.  For $175 USD, (6K Baht) I'd pull that trigger.  And not worry about that rustling sound in the attic later.

     

    Edit:  That's after checking the ampacity in conduit and being sure that's not going to cause an unintended consequence.  If you need to upsize the wire, that may blow the budget.  Sadly, all my ampacity charts are based on the NFPA published NEC and AWG wire.  (Yank stuff)  Not metric.  I'm sure someone here has an mm2 chart.

     

     

    https://www.doncastercables.com/technical-help/

     

×
×
  • Create New...