Last night I woke up about 3AM. I noticed my clock wasn't on. I thought maybe there was a community power outage. I got up to investigate. I then observed my outside lights to be off and other lights that are normally on during the night to be off EXCEPT for the Christmas tree lights that were operational on the Christmas tree in the living room. I thought that was odd and went to the breaker panel.
The MB was closed. ALL but one of the CBs were open. I had to cycle all of the open CBs to reset them.
This is not an issue of me misinterpreting the situation. The CBs were clearly open. As noted I had to reset all of the individual CBs and the home was not being powered evidenced by the lights, clocks, etc. being inoperable inside the home.
A similar type question has been asked on this forum some years ago; however, that appeared to me a misinterpretation issue.
My question is how is this possible? What would cause such a fault-a fault that would cause ALL but one CB to trip?
EDIT Folding comments thus far here
1.Jonathan S. - 15/17 CBs are GFCI – David (Armand edit: perhaps AFCI instead or combo, according to (9) below)
2.Hearth - I am in the U.S. Here is the link on the similar question. electronics.stackexchange.com/questions/367964/… – David
3.Ecnerwal; crip659 - Maybe a light drizzle off and on. Nothing noteworthy to my knowledge. – David
4.Jon Custer - Only 1 did not trip. That CB is GFCI – David (Armand edit: actually AFCI rather than GFCI according to (9) below).
5.Crip659 - my panel is a Square D panel. Home built in 2018. –David
6.ThreePhaseEel - just added photo. Position 12 is the only CB that did not trip. - David
7.ThreePhaseEel - As a side note, the breaker in positions 18 and 20 are for a sauna. I keep that CB open when I'm not using it. – David
8.George Anderson - Thanks for the insight. There is some construction going on in the neighborhood. I haven't talked to my neighbors yet. There's only a few of us. I'll have to put my detective hat on later to see what I can dig up. – David
9.Mazura - Apologies I wasn't differentiating b/w GFCI and AFCI or dual. The CB that did not trip is AFCI. I was able to speak to a neighbor. He said he had one breaker trip last night. I don't have any further info at this time. Appears it might be a PoCo issue. – David