by toylet you mean toilet right. Is that an american spelling?

Yeah he was just being silly

ahh now I see a play on words.

Yup I was joking at these eyesores that now infest the street light arms lol. It's still spelled "toilet" in the USA as usual.

Yeah these do look like toilets lol. BTW, I've seen mercs here with newer GE MV lamps work on some nights and not others. One light on my grandparent's street sometimes doesn't come on at dusk, rather it will randomly start a couple hours after it was supposed to. I've seen a MV M-250A cycle too, also with a newer GE lamp. Very odd! Could it be the bad arc tube seals the recent GE mercs are known for or does that sound like a weak starting resistor? That could explain the M-250R1 on my grandparents' street but the cycling M-250A is an oddball. I saw it on and when we got closer to it, it went out. I don't think the PC saw stray headlights and there didn't appear to be a power dip, as the other lights remained on. Maybe a loose wire...

Caltrans has been installing these in my area throughout the last two year. I know of one on the northbound side of the 71 after the Valley Blvd/Holt exit right before the interchange with the 10 and 57 north that has half the LEDs out. It's on a circuit that is day-burning so it should be easy to find. You may see it better on the southbound side after you transition from the 10 east to the 71

There's another group on the southbound 71 after Butterfield Ranch Rd/Euclid before you get to the 91 interchange that appears to be "out" but if you look closely at night, you could see the LED arrays glowing faintly. It's a group of 3 so I believe there's more of a voltage or wiring issue.

Oh yeah, the Leoteks here act the same way. There is one not far from my house that is intermittent. I also have seen some of the 80 led units with only half the diodes working. Also can find a dozen that are already not working and they are on the normal wooden utility pole tapped directly to the secondary.

Maybe this is a good thing for us though. Maybe LED's will turn out to not be as good as everybody thought they were for street lighting.

I don't know... seems like more of a quality issue rather than a technology issue. LEDs thenselves do have geat potential but they're limited by how much quality and deisgn effort (aka money) manufacturers put into them. Sounds like the LeoTeks use crappy drivers? AEL and Cooper both use Philips Advance LED drivers (which seem to be better than their electronic fluorescent ballasts lol). GE either uses their own drivers or Universal drivers since they seem to have a contract with Universal as AEL does with Philips.

I just hope LED's don't become the only available light source for roadway lighting. It will probably happen eventually. But hopefully not anytime soon. Mike, Like you said it seems more like a quality issue than anything else. For LED roadway lighting manufacturers to make better, longer lasting LED street lights, more money really needs to be spent making them better quality. Which is just going to push people away from LED.

yep, they want to bring down the cost of the fixture as much as possible to draw more people to them. i have a feeling that LEDs were take over street lighting by 2035. That's coming from the fact that HPS first started becomming popular in the 70s and has pretty much been dominant since the early-to-mid 90s. LEDs have started to become popular since roughly 2010 so by the mid 2030's they'll probably be dominant. And by around 2065-2075 the next lighting source after LEDs will probably be dominant for high-intensity lighting.

Induction and CMH seem to be good "green" options but i think CMH is loosing to induction and induction is loosing BIG time to LEDs. LEDs probably make up more than twice of what induction and CMH together make for new "green" lighting installations. I don't have any actual statistics on hand though but from what I've seen LED appears to be the winner... I'd much rather see CMH or even induction, since the fixtures and lamps resemble older HID technology but LEDs are the new hype. A major factor is that LEDs don't have mercury or other potentially dangerous chemicals (they have arsenic within them, which is even more dangerous so tell me how that's any better...) so they're seen as a "safer" lighting technology. I don't think the arsenic can be exposed but I'm sure those people in the factories in China would much rather be dealing with mercury over arsenic...

The weak point of LED systems is the electronics. Sometimes, a cracked or oxidized solder can cause intermittent operation. It has also happened in cree LED downlights, cree and philips LED retrofit bulbs, etc. I also have seen some cree led downlights develop a flash pattern after a while, and they are also slightly dimmer than those operating normally. Tricky, finicky technology thats for sure. By the way, LEDs use the energy of the electrical current to generate light, while incandescent and gas discharge lamps generate light from heat or a chemical reaction, which in this case is caused by the electrical current passing through the filament or the vapor of the chemical(s). Both incandescence and chemical reactions generate huge amounts of heat and non-visible radiation like UV and IR. For this reason, it is tough to compete with the efficiency of LEDs.

Ahh so LEDs emit only visable light?

I do know the leoteks do use the philips advance drivers. Mine have two if them installed in the fixture. I'm thinking it's more of the photocontrols causing the fixtures not to work. Holyoke uses the "20" years led suntechs and I'm sure not everyone will last that long. I've installed suntechs at work and seen them dayburning or not working within a few weeks of installation.

yeah sun-techs lately have not been great at all. The recent ones here that are dark and very sensitive tend to have a trend in dayburning on 250W M-250R2s here... If they want PCs to last 20 years (or more like 40+ years) then they need to start making PCs like they did back in the 60s... if the HPS changeout never happened, many lights would probably have their original 1960s PCs, still working after over 50 years...

Right now i think DTL is the best PC for your buck. Ripley probably makes the best PC but they're really expensive. Just like EYE makes reakky good lamps but cost an arm and a leg whereas Sylvania still makes great lamps for much less. Unfortunatly Sun-Tech seems to be turning into an economy brand like Philips.

Actually as of right now, DTL probably does make the best PC's. A power company near me has used Sun-Techs for years. But I noticed not too long ago, well maybe a few years ago, that they were trying out DTL's. Then recently, they were switching from Sun-Tech to DTL every few months. And not too long ago I noticed a lot of new-looking Sun-Techs dayburning. Ever since then, I think they stopped using Sun-Tech. And if you do happen to come across a DTL that is dayburning, you can't really complain because the prices on DTL's are WAY lower than any of the other big brands in PC's. FPL has switched to ALR (Area Lighting Research) electronic PC's, and they have been using them for about a year or so now. And I haven't seen one dayburning yet. But I think ALR's are in the price range of Sun-Techs.

Yeah DTL offers a lot of options too like AEL (well you'd expect that since they're owned by the same parent company). DTLs are the best now i guess and they're made in china while Ripleys and Sun-Techs are made in he USA lol.

Yeah. And DTL's may be made in China. But that doesn't mean they're not good. I rarely see new DTL's dayburning. And I have yet to come across a new DTL photocontrol with defects in the plastic. I have gotten new Sun-Tech's before that looked like the plastic cover wasn't molded correctly because either little pieces of plastic are still attached/hanging off of the cover, or I have gotten some where the whole cover looked lop-sided. Like a melted Ice cream cone or something
But the quality of DTL's is always consistent. Maybe DTL's LED photocontrols would be a good choice if the Sun-Techs are creating problems. Although, I don't have a problem with using Sun-Techs on LED streetlights. As long as the Sun-Techs keep damaging the LED streetlights

@Mike, correct, LEDs mostly generate visible light (not counting the infrared LEDs), but theres still a little UV and IR in the white LEDs. Most of the heat is the conductive kind, same as in your computer and other electronics. Thats why LEDs need heat sinking. I recently lit up some LEDs with a 9 volt battery and I was surprised how hot they got and how fragile they can be when subject to that much heat. Granted, a 9v battery without current regulation is way too much for a LED at least for more than a few milliseconds. The heat inside the LED die can burn the resin it is encased inside.

@antstar85, mike and HPSM250R2, in some cases it could be the PC, but that still doesn't explain why I see the same behavior in LED downlights and other indoor fixtures and these are operated by a switch, not a PC.

Seattle City Light has installed these Leotek LED fixtures all over the City, along with Beta LEDways and American Electric LEDs in a few areas. The Leoteks are my least favourite, and I don't like their daytime aesthetics, but I do like the purplish-blue tinge to the light at night.
I'm not sure what brand of photocontrols are used but as some of you have noted in other areas, they are set to come on when it is very dark and turn off when it is just beginning to get light. Also, there is no time delay anymore and the turn-on/turn-off points are too close; in some areas where there may be a bit of reflected light, lights will blink on & off when they first turn on and again right before they go off for the day. This is quite annoying, and in several cases I have seen a large group-switched series of lights cycle on & off like that. With HIDs the cycles are longer due to the restrike time (great for the lamps!) but with LEDs it's quite distracting!