100 watts to 600 watts within a minute same sun

blue
blue Registered Users Posts: 35 ✭✭
Ive been watching the voltage on my panels. It will sometimes jump from 100 watt output to 600 watt output within a minute with the same sun. Ive seen some variances even under load but mostly I have pretty good output. I have 1500 watts in panels at 8 -12 volt batteries at 24 volts . I was wondering if the 60amp epever solar controller would cause this in charging the batteries? Or perhaps the panels have an intermittent short somewhere. The panels are 3 banks of 5 panels at 100 watts each. 

Comments

  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    Difficult to say, if there are loads or clouds these factors could cause swings in wattage, but the interrelationship between voltage and power would be a better way  to determine if there is an issue, or if what's being seen is merely a dynamic change based on conditions. 

    The battery regulates the voltage, if the voltage drops along with power there could indicate a problem in the array or a passing cloud, if voltage remains stable but power increases that could indicate a load cycling on. Battery capacity along with state of charge will influence the degree of the swings, so in order to conduct a test the conditions would have to be controlled, no loads on a clear day with the battery partially discharged. This would allow the PV to provide as much current as conditions allow without being influenced by another factor, then carefully watch the voltage and wattage, or current depending on the display, there should be no radical swings. The type of controller PWM or MPPT is not mentioned, but PWM should remain more stable, clamped to the battery voltage whereas MPPT may vary in power to some degree as it tracks the maximum power point but these swings would be subtle, not major. 
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • mountainman
    mountainman Registered Users Posts: 439 ✭✭
    My epever does crazy swings also seems to get lost tracking. Drops from 300 to 100 watts for 10 seconds or so. In over cast conditions voltage will drop from 37 to 16 volts and get stuck there until I toggle the array breaker then goes back to 37 volts.
    2kw array 6 345 q cells  make sky blue 60 cc
     6 230ah GC @36 volts 
    18 amp accusense charger. 3650 champion 
  • Tecnodave
    Tecnodave Registered Users Posts: 437 ✭✭✭✭
    edited June 2019 #4
    That to me is a known problem with EP Solar tracer controllers, AKA EPEver, they have a faulty sweep algorithm, they tend to do just that when there is variable cloudiness. I had several and they all did that. There are better controllers that do track much better, but alas, they are more expensive than the Chinese imports. The only true test will be with partially charged batteries and observing the power output as cloud cover changes, if there is no change in cloud cover and the controller continues to do that you have a faulty controller and or bad wiring at some point in the system. Use of a good DVM will show up the faults. Yes the EP Solar controllers do get stuck at very low voltages and do not recover until you "reboot" the controller. I called for tech support several times and no solution was found. I was not able to get a solution to the problem until I bought American made controllers and the problem has never reappeared. I got rid of my tracers 6 years ago when I bought my first Classic's, no looking back, I want something "known" to work and have a good tracking algorithm, the classic has excellent tracking during constantly changing conditions. I also get excellent results from Morningstar's controllers which also have an excellent tracking algorithm.
    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,
  • mountainman
    mountainman Registered Users Posts: 439 ✭✭
    Actually morning star is made in Taiwan.
    2kw array 6 345 q cells  make sky blue 60 cc
     6 230ah GC @36 volts 
    18 amp accusense charger. 3650 champion 
  • Tecnodave
    Tecnodave Registered Users Posts: 437 ✭✭✭✭
    I did not know that, I bought mine at a frea market for $25 so I got my money's worth, The only manufacturers that I buy now is MidNite Solar in Arlington Washington, USA, I bought a used MagnaSine MS4024AE to tide me over until MidNite releases the new MidNite Rosie the Inverter. Disclaimer....I am a retired electrical engineer and hate sloppy engineering....also a MidNite beta tester, so maybe I'm a bit biased
    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,
  • boB
    boB Solar Expert Posts: 1,030 ✭✭✭✭
    edited June 2019 #7
    Mountainman said....
    "Actually morning star is made in Taiwan."

    Yes and they don't have tariffs either.

    Morningstar is pretty good stuff though.  And friendly people.



  • Tecnodave
    Tecnodave Registered Users Posts: 437 ✭✭✭✭
    I do admit I have several Morningstar products and have few issues with them, the sun saver line is very good quality,  they are my go to for low cost charge controllers, but I prefer the programmability of the MidNite charge controllers.
    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,
  • Makers
    Makers Registered Users Posts: 16 ✭✭
    The epsolar/ever controllers if reading from the main charge controller, will update very slowly. If using the add on box, it will update faster, at least the readout will. I use shunts with mine, and they show me the controller is updating very quickly. Also I have noticed that when the controller is switching from bulk to absorb, or absorb to float, it will take a few moments for the controller to switch modes properly. IE it only produces 50-100 watts until it switches into the new charge mode