This is the first place have I seen the bare aluminum poles retrofitting new Traffic Signals on the pole. The signal before was on a seperate small pole infront of the streetlight pole like typical setups across Ontario, and those wasteful garbage LED's that were installed a year ago too. Yes they are still dayburning unfortunatly. -__-'
Ah for some reason, when RIDOT installs new lighting systems they use relays and the fixtures all have PC sockets with shorting caps (except for some OVF installations) but yet when they replace knock-downs the light usually doesn't have a PC socket. So it's fairly easy to pick out spot replacements since the general "rule of thumb" is that original lights have PC sockets with shorting caps and replacement lights have no PC socket.
I enlarged the picture and can see half the LED panels don't work in the light on the left. . I wonder if that signal is there temporarily because of construction. The construction is for a huge watermain running north to feed Brampton.
Are the OVXs the only HPS right there? The other lights all look like LEDs. If so then maybe this is a temporary pole and they didn't want to "waste" LEDs in a temporary set-up (though they could just transfer the temporary LEDs to the permanent pole when the time comes if they wanted to use LEDs...)
The middle pole behind me in the middle has a 400w R7 and a 400w OVX. The street running to my left and right has new steel octogonal poles with AE 125's. Heres the streetview from before.
Im pretty sure the signals on those poles are there to stay. Because that intersections is done. The construction crews have been ripping out the medians and the old poles bases.
The OVX is technically no bigger than an R7 because the reflector and refractor are the same. You could stick a 400W HPS lamp in a four foot long cobrahead but if you use a small sized reflector the lamp won't last any longer than it would in another small light. The M-250A2 was also made in 400W HPS in the 90s. The lights here really don't have cycling issues that I notice. I think your fixtures up there just have junk lamps...
LED's aren't all bad, but they need to do something about the LED's that waste energy being on all day. xD
But yeah, interesting that they moved it, maybe they wanted to save space or just do something else. I dunno.
Any small fixture can have 400w HPS, I mean they do use other fixtures then just OVX's. There have been some 400w M-250 R2's before am I right?
I mean they just tend to use OVX's because the OVX is a bit bigger then other small cobraheads. Though I still don't recommend 400w in an OVX. Though 250w HPS can do better in an OVX then an M-250 R2. Though still not recommended.
Always great hearing different spins on why lights fail! I was being sarcastic about OVX's replacing small fixtures 'for the better' . I've been of the opinion that some small fixtures overheat more than others causing fails.
Question for the panel, My electrical knowledge is the weak point here, if a lamp fails by cycling, I imagine other components become stressed/overun. What components in the fixture could fail next because of a cycling lamp?
I don't think the M-250R2 was made in 400 but I could be wrong. I know the M-250A2 was since we have some (and they do quite well for 400W lights too) The reason why your fixtures are failing is because their Coopers The lower wattage Coopers seem to do ok. Even the 250W HPS OVZs do ok here but the OVXs seem to fail here. All the OVXs here are 400W. Having all the gear stuffed up inside that little housing is bad too since it makes the ballasts and capacitors more likely to overheat.
It depends on the fixture design and ballast design when it comes to overheating. Also the fixtures could be failing just because they're crap... Oh BTW, the 115 is offered in 400W HPS too. I wonder how those do...
Only HPS and PSMH lamps (lamps with an external igniter) cycle. MV and conventional MH lamps do not cycle. Cycling has no effect on the ballast or capacitor however the igniter is effected. The igniter is what starts the lamp and when a lamp is cycling, it's starting several times a night and then there's the unlucky fixture that is also a dayburning cycler so it's cycling 24/7. Igniter life is very random. Some fixtures will die after just a couple lamps left cylcing and other can have a cycling lamp for years.
also, when a lamp does a hot-restrike, it takes life off the igniter too because it has to strike several times and strike more powerfully to restart a lamp. When a lamp is cylcing, the igniter is continuously trying to start it while it's off. It's the same effect as cutting the power to the light for a split second and then plugging it back in, though a cycler can remain off for a while whereas a good lamp will glow dimly as soon as power is applied and will start back up within a minute or two. Hot restrikes also hurt HID lamps of any type. One hot restrike can shave a considerable amount of life off a lamp.
If a lamp is left cycling and cycling endlessly, it will eventually just quit striking, either because the arc tube leaked or just because the electrodes are too worn out to even strike an arc. Frequent hot restrikes and cylcing makes the arctube hotter which can make the arctube seal fail (causing a leaked lamp) or can destroy the electrodes. But eventually the lamp will just die completely and if that happens, you'll probably hear a high-pitched BZZZZZZZZZZ sound, which is the igniter trying to start the lamp. The igniter will keep trying and trying to strike in some cases. In other cases the igniter doesn't keep trying to start the lamp. I think it depends how the lamp fails.
Normally lamps will keep cycling until they're replaced. Some lamps can also leak or fail without cycling but those are factory defects and abnormal for HPS. HPS cycles because it has an external igniter that can't recognize that the lamp has reached the end of its life. MV and MH have internal starting probes that start the lamp and I guess they can "sense" when the lamp fails. I'm not 100% on how the lamps function but HPS lamps are probably the most sensitive of the HID family. MV is the least sensitive. MH isn't really "sensitive" but the lamps can explode at EOL, generally it's more common for MH lamps running horizontally. Vertically oriented MH lamps are less likely to explode and they actually run better vertical (higher lumens, longer life) unless they're specifically designed for horizontal-only operation.
Actually, HPS cycles at the end of life because over time, the voltage required to maintain the discharge in the lamp get's higher then the ballast lets it.
So basically, how it works, is the electrical ballast that is in each light, it limits current and voltage to keep the lamp stable, thus the term "Ballast". And the ballast will only allow up to a certain amount of voltage/current. (Current is Voltage Divided by Resistance, so basically, the type of material the wire has is the resistance, copper has lower resistance, so it's more efficient. The higher the voltage, the more current with anything.) So, when an HPS lamp is new, the voltage required to maintain the lamp's discharge isn't high enough, and as the lamp gets older and has more use, the voltage required to keep that discharge going gets higher. So after the voltage required to maintain the discharge exceeds the maximum voltage the ballast gives out, then the lamp turns off. Basically, when you turn on the light, The discharge warms up and it still lights, and as the discharge warms up more, it needs a higher voltage. If the lamp is old enough, the lamp will reach the point where the ballast won't let the voltage go any higher, so the discharge fails, and the light turns off. But then the light cools down, and then it gets cool enough to strike again, so it turns on, then off, then on, then off, then on, then off, then on.. Blahblahblah. Basically after it turns off it's too hot to turn back on, so it has to cool down before it can stike again.That is how cycling works.
The ballast does limit the current but it's not the ballast that "gives out", it's the lamp's arc tube. A MV or MH lamp won't do that. It's like operating a fluorescent lamp on an instant start electronic ballast instead of a magnetic rapid start ballast. When a fluorescent lamp dies in a rapid start ballast, that's it. But with instant start electronic, the lamp will still work for a short time after. The remote igniter works the lamp harder than the internal starting resistor. The voltage is much higher too with start-up so a dead MV will often still work on a PSMH ballast with the igniter connected. It won't work on HPS under 200W because 35-150W HPS has a ~55V arc voltage while Mv has a ~130V arc voltage. There are ~100V 150W HPS lamps. 200-400W HPS is always ~100V so 250W MV will light on 250w HPS and 400W MV on 400W HPS ballast.
The reason the voltage required increases is because the gas content get's used up over time, throwing the specifications out of whack. But the lamp doesn't simply do a hot restike. It can be as short as a hot restrike or take as long as 10 minutes. It's random. It find newer lamps seem to cycle on and off faster while a single on/off cycle for an older HPS lamp seems to be longer.
The cycling definetly has something to do with the external igniter though... And it's weird how probe start MH lamps don't cycle yet PSMH do. The only difference is higher pressure in the arctube (allowing higher lumens and CRI) and an external igniter for a faster restike time.
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Im pretty sure the signals on those poles are there to stay. Because that intersections is done. The construction crews have been ripping out the medians and the old poles bases.
But yeah, interesting that they moved it, maybe they wanted to save space or just do something else. I dunno.
Any small fixture can have 400w HPS, I mean they do use other fixtures then just OVX's. There have been some 400w M-250 R2's before am I right?
I mean they just tend to use OVX's because the OVX is a bit bigger then other small cobraheads. Though I still don't recommend 400w in an OVX. Though 250w HPS can do better in an OVX then an M-250 R2. Though still not recommended.
Question for the panel, My electrical knowledge is the weak point here, if a lamp fails by cycling, I imagine other components become stressed/overun. What components in the fixture could fail next because of a cycling lamp?
It depends on the fixture design and ballast design when it comes to overheating. Also the fixtures could be failing just because they're crap... Oh BTW, the 115 is offered in 400W HPS too. I wonder how those do...
Only HPS and PSMH lamps (lamps with an external igniter) cycle. MV and conventional MH lamps do not cycle. Cycling has no effect on the ballast or capacitor however the igniter is effected. The igniter is what starts the lamp and when a lamp is cycling, it's starting several times a night and then there's the unlucky fixture that is also a dayburning cycler so it's cycling 24/7. Igniter life is very random. Some fixtures will die after just a couple lamps left cylcing and other can have a cycling lamp for years.
also, when a lamp does a hot-restrike, it takes life off the igniter too because it has to strike several times and strike more powerfully to restart a lamp. When a lamp is cylcing, the igniter is continuously trying to start it while it's off. It's the same effect as cutting the power to the light for a split second and then plugging it back in, though a cycler can remain off for a while whereas a good lamp will glow dimly as soon as power is applied and will start back up within a minute or two. Hot restrikes also hurt HID lamps of any type. One hot restrike can shave a considerable amount of life off a lamp.
If a lamp is left cycling and cycling endlessly, it will eventually just quit striking, either because the arc tube leaked or just because the electrodes are too worn out to even strike an arc. Frequent hot restrikes and cylcing makes the arctube hotter which can make the arctube seal fail (causing a leaked lamp) or can destroy the electrodes. But eventually the lamp will just die completely and if that happens, you'll probably hear a high-pitched BZZZZZZZZZZ sound, which is the igniter trying to start the lamp. The igniter will keep trying and trying to strike in some cases. In other cases the igniter doesn't keep trying to start the lamp. I think it depends how the lamp fails.
Normally lamps will keep cycling until they're replaced. Some lamps can also leak or fail without cycling but those are factory defects and abnormal for HPS. HPS cycles because it has an external igniter that can't recognize that the lamp has reached the end of its life. MV and MH have internal starting probes that start the lamp and I guess they can "sense" when the lamp fails. I'm not 100% on how the lamps function but HPS lamps are probably the most sensitive of the HID family. MV is the least sensitive. MH isn't really "sensitive" but the lamps can explode at EOL, generally it's more common for MH lamps running horizontally. Vertically oriented MH lamps are less likely to explode and they actually run better vertical (higher lumens, longer life) unless they're specifically designed for horizontal-only operation.
So basically, how it works, is the electrical ballast that is in each light, it limits current and voltage to keep the lamp stable, thus the term "Ballast". And the ballast will only allow up to a certain amount of voltage/current. (Current is Voltage Divided by Resistance, so basically, the type of material the wire has is the resistance, copper has lower resistance, so it's more efficient. The higher the voltage, the more current with anything.) So, when an HPS lamp is new, the voltage required to maintain the lamp's discharge isn't high enough, and as the lamp gets older and has more use, the voltage required to keep that discharge going gets higher. So after the voltage required to maintain the discharge exceeds the maximum voltage the ballast gives out, then the lamp turns off. Basically, when you turn on the light, The discharge warms up and it still lights, and as the discharge warms up more, it needs a higher voltage. If the lamp is old enough, the lamp will reach the point where the ballast won't let the voltage go any higher, so the discharge fails, and the light turns off. But then the light cools down, and then it gets cool enough to strike again, so it turns on, then off, then on, then off, then on, then off, then on.. Blahblahblah. Basically after it turns off it's too hot to turn back on, so it has to cool down before it can stike again.That is how cycling works.
At least to my understanding.
The reason the voltage required increases is because the gas content get's used up over time, throwing the specifications out of whack. But the lamp doesn't simply do a hot restike. It can be as short as a hot restrike or take as long as 10 minutes. It's random. It find newer lamps seem to cycle on and off faster while a single on/off cycle for an older HPS lamp seems to be longer.
The cycling definetly has something to do with the external igniter though... And it's weird how probe start MH lamps don't cycle yet PSMH do. The only difference is higher pressure in the arctube (allowing higher lumens and CRI) and an external igniter for a faster restike time.