So a few months ago I was driving by a church that is on my route, and I noticed something really weird. The Ael 115 on the side of it was really nice and lit up. Except, my whole life living around here, I’ve never seen it turn on. Then the next day, the light was dead. Pitch black over there like usual. I’ve seen this happen to some other fixtures in my area too, it’s really rare, but really weird. What do you guys think happens to make them stay turned on for one night but then cycle the next night?

Could be a coincidence. Maybe every time you drove by, it was mid off-cycle, and then this time it happened to be on. I suppose an intermittently working ignitor could be the cause, but IDK if that is likely. Some lamps take really long to cycle, I have seen one that takes around a half hour to cycle off.

Or maybe it is some sort of other intermittent connection, that is possible.

Yeah maybe. That one just… I never have even seen that light in any stage of cycling, except in 2016 I had to do a summer church camp thing there and it was lit up back there, but that was 10 years ago, so there’s to telling what stage of life that lamp was in at the time.

Maybe it's manually-switched? Also lamps can sometimes cycle on/off just once per night, or less....There was an AEL 125 by me in 250w HPS with a lamp installed in 1999... well by 2018 it turned on for about 15 seconds once every week or so. I asked my buddy, who lives across the roadway, to take note of when it was on in the evening. Of course, he may have never noticed it coming on in its brief mercury phase, but I VERY rarely saw it lit, and I would drive by every evening or so.

Yeah, it shouldn’t be switched, since it’s on a utility pole with a 3 phase transformer on top, but yeah. It could just have been a really luck sight. It was just so bizarre how it was really bright. The lamp isn’t that old, the church was completely rebuilt after it got struck by lightning in 2005. The streetlight should be from around 2007. Ael 115*

Failing photocells, ignitors, and users switching on breakers which function they don't know, explain a lot of things. (i mean, users in a commercial setting tripped some circuit. Then they go to a DB and reset something else, that might have been tripped or manually off for years)

Another option, if it is controlled via some timers etc, those often default to "ON" after a power outage until somebody sets the time again, even if there ar no switching hours configured

Not HPS, but there used to be an old GE M250 dayburner on a street here that would work only sometimes. Maybe the photocell on it was intermittent.

Really? Since there is no reason for me to go over there, I never have gone and checked if the bulb was leaked or failed, so I wonder if it just starts every couple of months. I suspect a failing ignitor, because it was super bright that one time, then it never started again. It seems like the streetlights around me have had lots of starting issues over the years. I’ve seen at least two that were humming loudly, but never turned on or slightly glowed, but the bulb was fine.