That's rather cool Alain!!! Thanks for sharing! And welcome back as well as welcoming myself back!

LOL I always laugh at how all these residential light fixtures have adjustable PCs. My 70W PSMH Utilitech wall light from Lowe's had some special cap for the button style PC. The problem is, these residential PCs are already pretty unsensitive to light, so with the cap on, my light would dayburn all morning until around noon-time when the sun comes around the backside of the house (the back of the house faces west). So I just took the stupid thing off altogether and now it's more sensitive, although still relatively insentive.

How does this secure to the PC? Does it just go right over it without latching to it at all? It seems like the cover would just lift upward and off the PC if the wind was just right. Afterall, the wind can lift out the entire PC if it's not properly locked in (I've seen it plenty of times and other times where the base stays in place and the cover of the PC blows off). A couple times I've heard of the PC socket itself actually cracking and breaking (typically on an older light that's been dayburning for years) where the PC falls out because the PC socket is all cracked and nothing's left to hold it in. Or sometimes the PC cracks and falls apart when the lineman goes to remove the old dayburning PC after years of heat drying out the plastic.

Yes, it just snaps over the top of the photocontrol. I rarely see these in use on the fixtures that were supposed to have them. My guess is most of them break after getting brittle from the heat over the years, and the rest are discarded when the photocontrol fails and is replaced.

It actually surprises me how many people don't realize that the photocell comes off the light. One of my teachers had a yardblaster (could have even been a NEMA head since his house is from the 60s) and he noticed that one day it stopped shutting off in the morning. He had moved into the house in the late 7s or early 80s or something and the light worked great dusk-to-dawn until around 2009-2010 when the PC died. He said he didn't know what actually controlled the light so he just bought a new yardblaster and that one failed after a month (it must have been a Lithonia 100W PSMH yardblaster since he bought it at Home Depot). So he bought another and it failed too. So he finally just gave up and just installed a motion sensor flood light instead. He regrets not saving the old NEMA head, which he said was still fine other than it running 24/7. Had he known that the solution to the problem was a $10 part, he would have kept the old light. Those yardblasters sold in stores now are such junk it's just terrible. I showed him an AEL Series 11 NEMA head PDF and gave him an ordering number (this was last year when I had him as a teacher) but he said he's just going to leave the motion sensor flood up. The ordering number was for a 100W PSMH like he had bought as replacements for the 175W MV NEMA. I gave him numbers for standard bucket optics and the FCO ''dog cone'' optics (Sky Guard i think it's called?)

I know some of my teachers well enough I'd fix it for them. In fact, the guy many of my F40 lamps and a few fixtures are from was one of my teachers. Before getting those fixtures I had replaced some bad lamps a few months before.

Hmmm I thought a teacher would had more common sense One would think while looking over the light what the thing on the top,it says "Photoelectric Control" on the top of it,oh it twists back and forth....I wonder what happens if I pull up on it,ah it comes off! Maybe this turns the light off and on.

Yeah but in their defense it's probably 10-20 feet up, and if you're not familiar with lighting and/or scared of heights it's not like you'd know that. If it was a construction/shop teacher I'd think it was pretty lame but otherwise, yeah.
This former teacher of mine also did maintenance for the school and knows what a Universal Therm-O-Matic ballast is though! (In addition to replacing a ballast). I have however told him about the dangers of 34 watters old older ballasts though.
Although he did once ask me: "Can you still even GET 40 watt tubes anymore"? (Being used to the 34w stuff used by places like schools in the 90s-ish when he worked there)

Yeah true,would have thought when he bought the new 100W PSMH Yard Blaster to replace the dayburner that it might have "clicked" when he unboxed the PC and installed it on top while assembling the new blaster.

AND given the old light to Mike!

Yep

LOL well he was my history teacher last year (10th grade ''World History II'', formerly known as ''Modern European History''. The light had been replaced back around 2009 or 2010-ish, so I was actually still in elementary school. I wouldn't have known much about lights back then anyway. I noticed lights at that point, but had minimal knowledge about them.

Yeah you'd think he would have noticed but I think he probably had an electrician do the work and if my teacher simply said "take this light down and put up this one", the electrician would have done so with no questions asked. Some people are so afraid to even do minimal electrical work and others have no problems doing their own electrical work. Typically the people who do their own electrical work are the ones who shouldn't be doing it though. He said he wish he knew me when the light started dayburning since I could of told him how to fix it (heck, I would have given him a PC too, since I have a bunch.) I think he mentioned the refractor was missing a chunk on the bottom too but he had never bothered with it since it didn't affect performance (the light's already open-bottom). I wonder what the old NEMA head was. The lamp was probably a lifeguard since it was a BT28 (I drew a picture of a BT and ED lamp and asked him which it looked like. He said he's pretty sure it was a BT) and it was coated. I say lifguard because if it made it from before the early 80s to the late 2000s without dimming to the point of uselessness, it must have been a lifeguard lamp. I wonder what brand the NEMA head was. NEMA heads weren't used by the electric company around here (bracket arm fixtures were used a little but they're extremely rare to find) so the previous owner of the home must have gotten it from a hardware store or from an electrical supply.

Might have been an old Norelco yardlight.

could have been.

I have one of those somewhere. The cool thing is that since those photocells are knock-offs of ALR photocells, they will fit similar style ALRs.