breaker keeps tripping on enphase system

sharktoesharktoe Registered Users, Users Awaiting Email Confirmation Posts: 1
I have a 3 arrays of panels. 50 panels total. from the panels. From the panels I have 3 20 amp breakers, then to a switch and to a 60 amp breaker. One of my 20 amp breakers trips often. I installed a new breaker, but did not help. Sometime works for a week or so, sometime just a few hours. Has some else seen this. Is one of my M210 micros causing this or is this a panel issue. How would I troubleshoot this?
Thanks for your help and time


  • BB.BB. Super Moderators, Administrators Posts: 32,205 admin
    Do you have an AC current clamp meter?

    In general, a 20 amp breaker will never trip below 17 amps (0.85 of name plate).

    May trip at 20 amps (minutes to hours).

    Above 20 amps, will trip faster, but usually takes many amps over 20).

    My first guess is that you have too many panels and gt inverters on one string (miss wiring?).

    Second guess is your 240 VAC line voltage is too low of voltage (closer to 210 vac or less... Possibly 208 3ph?).

    The third possibly is that you have a great micro inverter going bad that is occasionally putting a short circuit on the AC line.

    I had a central inverter that did this... But if this happens, I would expect that you would have a dead inverter after the first time (my inverter died after the first breaker trip).

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SolfyrSolfyr Registered Users Posts: 22 ✭✭

    Posting from Europe , got me a datasheet of the 190 version :

    21 units alowed to either a "leg" or a "branch" with the 208V 3phase version ,

    or 15 units with the 2x120V 240V Split Phase version .

    Not sure , if the 210er is much different .

    51/3 strings is 17 , therefore 50/5 sounds reasonable ,

    but 50/3 a bit asynchonic .....

  • BB.BB. Super Moderators, Administrators Posts: 32,205 admin


    What is the current rating of the branch circuit? The 208 circuit, is it >20 Amp breaker? Nominally, the same 190 version would output less current on a 240 VAC circuit vs a 208 VAC circuit (Power=Voltage*Current, higher voltage, lower current for same power/Watts).


    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SolfyrSolfyr Registered Users Posts: 22 ✭✭

    Curent rating :

    Split Phase 240V : ACout Amps 0.8 (800 mA) -> x15 = 12 Amps

    3phase 208V : ACout Amps 0.92 (920 mA) +> x21 = 19.32 Amps

  • billybob9billybob9 Registered Users Posts: 141 ✭✭


    I have an Enphase system on my house and monitor each panel on the internet. My 4k system is one string and that's all I need. If I had a bad Micro Inverter I would see it right away. I would think the M210 would be either dead or alive but that hasn't happened to me yet so good luck in tracking it down. BB

  • SolfyrSolfyr Registered Users Posts: 22 ✭✭

    4000 W ÷ 250 W = 16 micros .

    Usually , the output of Amps is less than the optimum , and therefore probably works with one more , than noted in the datasheet .

    The OP has too many Amps being supplied into the one string of ?number of? micros .

    Assuming Three Phase , it could be possible , that some crazy constellaton had been installed ,

    like 13 East, 13 West , and 24 South , thus the southern string supplying too many amps occassionally ...

  • jonrjonr Solar Expert Posts: 1,386 ✭✭✭✭

    I expect the OP is long gone.

    I am available for custom hardware/firmware development

  • SolfyrSolfyr Registered Users Posts: 22 ✭✭

    Danger of Mismatch : The manual for the M190_M210 allows only 15 A max circuit breakers , but the next generation M250_M215 then allows 20 A breakers .

    While the AC cable for Splitphase and Threephase is interchangeable at the former version , the later has different cables for Split and Three Phase .

    External grounding wire not required anymore , for the non-original 250_215 , since inside the new Engage Wire .

    For M190_M210 there is also an AC amps maximum given , that exceeds the "typical" AC-Aout in the datasheet by almost 15% , as for the M210-84-208-S1x typical 1000 would max at 1147 mA .

    Imaginable is a mismatch of newer and older inverters , either by adding panels , or usage of old hoarded micros , together with newer ones , especially the original M215-60-2LL-S22 , that still needed Ground Electrode Conductor , and probably used the same AC cables , as the M190_M210 .

    if installing a mix of IG (Integrated Ground) and non-IG microinverters, install the non-IG 

    microinverters closer (electrically) to the junction box to minimize GEC use

  • razrVrazrV Registered Users Posts: 2
    Does anybody know what normal wait time on the telephone with Enphase is for service? Also how quickly do they send out warranty parts?
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