Solar MC4 wiring question

Hi everyone. I have a weird wiring issue that I'm trying to track down and would love some help troubleshooting. I have 3 separate runs of two (pos/neg) wires from my arrays to my house. All 3 arrays have separate breakers so that, in an emergency if that occurs, I can shut off power. That said, on two of the circuit breakers, if I turn either of the two breakers off, it turns off power to both power sources. Any ideas what would cause this issue? Any help would be greatly appreciated. Thank you!

For further clarification, the 3 strings with the following setup:

* Two renogy 550w panels to Ecoflow Delta Pro (string 1)
* Two renogy 550w panels to other Ecoflow Delta Pro (string 2)
* 6 405watt panels (3s2p) to Victron 250/100 which goes to separate 48v battery (string 3)

Sounds like you have got two of the wires crossed over somewhere. Follow them back and make sure they're going to where you thought they were going.

Kiwi2000 said:

Sounds like you have got two of the wires crossed over somewhere. Follow them back and make sure they're going to where you thought they were going.

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Sorry for the dumb question but just to make sure I understand 100%, you mean trace back to ensure I have the pairs correct, right?

Blown284 said:

Sorry for the dumb question but just to make sure I understand 100%, you mean trace back to ensure I have the pairs correct, right?

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Yes do that. Because if you have them mixed up somewhere, shutting off a positive or negative on either string would shut the circuit down.

Kiwi2000 said:

Yes do that. Because if you have them mixed up somewhere, shutting off a positive or negative on either string would shut the circuit down.

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What if I swapped negative wire from one side to the other?

Figured it out. I had one negative from one array swapped by accident. All sorted now. Thank you for the help.