# 277 volt standards



## Dennis Alwon (May 9, 2009)

I don't think the voltage is the issue but you should check the led's as they usually work on many voltages.


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## nrp3 (Jan 24, 2009)

I just replaced some drivers in some LED parking garage lighting about a year old. Some of the LED's themselves were out as well. What caused, who knows. I notice surge suppression is an option on many new fixtures. Guessing there's something to this.


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## CoolWill (Jan 5, 2019)

OP should check the integrity of his neutrals.

As far as SPD, I try to sell it to my LED customers every chance I get.


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## joebanana (Dec 21, 2010)

Figure peak voltage for 277v. is about 391v. But if they're rated for 277, they should have a fudge factor of a few volts over. Contact the manufacturer and ask them what kind of over voltage protection they have.


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## nrp3 (Jan 24, 2009)

While I'm thinking those small devices they sell as options for led fixtures are a good idea, are they likely to do anything for these sorts of voltage issues? Kind of figured they'd be more for lightning, etc.


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## frenchelectrican (Mar 15, 2007)

nrp3 said:


> While I'm thinking those small devices they sell as options for led fixtures are a good idea, are they likely to do anything for these sorts of voltage issues? Kind of figured they'd be more for lightning, etc.


It should be a standard feature to put in some kind of device like movs or some type of surge arrestor in there and I know some of ya readers may recall I did have a bit of issue with them last year with my 240 volt line to neutral system.


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## nrp3 (Jan 24, 2009)

The question I'd have is would they lose their effectiveness by putting the device at the base of the pole at the handhole? Have an LED indicator on it showing its still good like a lot of the panel mounted ones. Renting lifts is expensive.


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## frenchelectrican (Mar 15, 2007)

nrp3 said:


> The question I'd have is would they lose their effectiveness by putting the device at the base of the pole at the handhole? Have an LED indicator on it showing its still good like a lot of the panel mounted ones. Renting lifts is expensive.


like a remote monitor LED light on handhole ? I think it is possible to do that otherwise a whole unit can fit in the handhole IIRC they are not very big at all. but I think the surge suppresser may work in that arrangement I know I did one parking lot luminaire set up and it was not too bad but only one drawback is that I did not have led indication light if the surge protection is there.


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## nrp3 (Jan 24, 2009)

That’s one step better, I figured just having it where it’s more accessible for easy replacement or at least being able to check it without having to rent a lift would be good.


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## frenchelectrican (Mar 15, 2007)

nrp3 said:


> That’s one step better, I figured just having it where it’s more accessible for easy replacement or at least being able to check it without having to rent a lift would be good.


Ya know what ?? 

I am thinking a very simple solution to this is a simple twistlock photocell housing type just easy on and easy off to swap it and the size is about right there for that purpose so you can put a twistlock photocell type receptacle in the base handhole. 

I think that will work very well especally with very tall parking luminaire or large roadways unit.


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## splatz (May 23, 2015)

I don't think that surge protection, MOV's, etc. are going to do anything for a chronic overvoltage like this. Surge protection and power conditioning are two separate things. 

The MOVs work by shunting voltage to the EGC when the voltage rises but they don't start to clamp / shunt until there's a significant overvoltage. 

If they did clamp at 300V, you still have a problem, the MOVs don't last all that long, they shunt some energy and then they are shot. If they fail off, you'd have MOV replacement calls instead of light replacement calls. If they fail on, they'd just delay the eventual replacement of the light and the MOV at the same time. 

Again IMO the problem isn't the LED it's the driver, the low voltage power supply. The real solution is DC distribution rather than AC. Without totally reinventing the wheel (maybe just reinventing the tire) for parking lot lights the solution would be LEDs up top, power supplies / drivers in the handholes.


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## nrp3 (Jan 24, 2009)

That's what I, those surge devices were more for "events" than day to day smaller voltage issues. Maybe the drivers need to be good for 120-600v. This is the thing I fear with LED lighting, we are selling something that's supposed to last, but when drivers get wiped out by small voltage fluctuations, we aren't really getting anywhere.


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## splatz (May 23, 2015)

I am curious where was the 300V measured on the weekends, at the service or the lights? 

I don't know what the local power company's obligation would be, but I thought they were usually required to regulate service voltage to +/- 5%. If the source of the problem is fluctuations at the service, a 5% overvoltage at 277V it should translate to a max of 291V. 

Is it possible the transformer that feeds the lights was tapped a little hot to compensate for voltage drop under load, and with the reduced load that the LED lights draw, and other loads off on the weekends, the voltage drop isn't there, so you're seeing this overvoltage?


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## frenchelectrican (Mar 15, 2007)

splatz said:


> I am curious where was the 300V measured on the weekends, at the service or the lights?
> 
> I don't know what the local power company's obligation would be, but I thought they were usually required to regulate service voltage to +/- 5%. If the source of the problem is fluctuations at the service, a 5% overvoltage at 277V it should translate to a max of 291V.
> 
> Is it possible the transformer that feeds the lights was tapped a little hot to compensate for voltage drop under load, and with the reduced load that the LED lights draw, and other loads off on the weekends, the voltage drop isn't there, so you're seeing this overvoltage?


That kinda remind me if you recall there were a thread sometime back with led driver go to hecks when the POCO finally fix the voltage regulator and capacitor on their system.

IIRC there were few of us discussing on that thread. and yes it was instering one.


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## splatz (May 23, 2015)

I found this googling regarding the 5% tolerance...

https://www.pge.com/includes/docs/p...ergystatus/powerquality/voltage_tolerance.pdf



> *Voltage Tolerance Boundary*
> The only national standard for utilization voltage regulation is ANSI C84.1. Its title is American National Standard for Electric Power Systems and Equipment – Voltage Ratings (60 Hertz). The first version in 1954 was a combination of two standards, one from the Edison Electric Institute that represents utilities and the second from NEMA ...


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## MikeFL (Apr 16, 2016)

Our county public works dep't has problems just like OP describes. The lighting manufacturer required a power quality study prior to warrantying the 277V LED lights. When they saw it peak at 305V they said they're not warrantying the lights because it went over 300V.

I have spoken about it to LED lighting manufacturers who say that's hogwash. If the lights are failing because of 305V they have failed to mitigate heat.


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## nrp3 (Jan 24, 2009)

I’d think the guys out west would be seeing similar problems. We’re not where we should be with these products. There shouldn’t be a need for PQ studies for lighting upgrades. The drivers need to be more robust.


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## trentonmakes (Mar 21, 2017)

The only problem I know of we have are with these bulbs, when converting to LED

It seems the issue is, they put out too much heat in the enclosure and fail prematurely. 

I haven't heard of any issues with other bulbs or LED lighting that we use.









Sent from my LG-K550 using Tapatalk


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## nrp3 (Jan 24, 2009)

I just gave a quote for both (something similar to those) and complete fixture replacement, highly recommending replacement because I'm not going to eat the cost of a lift rental everytime one of those expires prematurely, even if the supply house is providing new ones in the five year warranty period. I am worried about the thermal management with those. I think they have their place and there are instances where I use them. This was 30 ft up and I'm not eating the cost of the lift to figure out whether the shoe box meets the minimum size or not in the specs. The low bidder can have that.


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