100-277 volt lights - are two ungrounded conductors ok?

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Electrically wise it may work, but it says neutral meaning someone wanted a grounded conductor. Whether actually needed is debatable.

Technically it could even work off a high leg and noodle, but not something that should be done.

I have no idea if it could somehow tell whether one conductor is grounded or not.

I know the fluorescent ones cannot as I have used them on every voltage available with the 120-277V ballasts available now.
 
jumper said:
Electrically wise it may work, but it says neutral meaning someone wanted a grounded conductor. Whether actually needed is debatable.

Technically it could even work off a high leg and noodle, but not something that should be done.

I have no idea if it could somehow tell whether one conductor is grounded or not.

I know the fluorescent ones cannot as I have used them on every voltage available with the 120-277V ballasts available now.
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The typical linear fluorescent depends on capacitive current through the glass wall to the reflector behind the bulb as part of the starting process. Use an ungrounded source and such a combination will not work. As for L-L from a grounded system, not sure from the theory side.
 
GoldDigger said:
The typical linear fluorescent depends on capacitive current through the glass wall to the reflector behind the bulb as part of the starting process. Use an ungrounded source and such a combination will not work. As for L-L from a grounded system, not sure from the theory side.
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But this is an LED source, not a ballast. Probably wouln't care, although it's also likely an SMPS, so common mode noise might be an issue.

That said, why not just run a hot and neutral (120V) instead of 2 hots for 208V? It's exactly the same number of wires...
 
GoldDigger said:
The typical linear fluorescent depends on capacitive current through the glass wall to the reflector behind the bulb as part of the starting process. Use an ungrounded source and such a combination will not work. As for L-L from a grounded system, not sure from the theory side.
Click to expand...

These were basic grounded systems, so I am a bit unclear what you are saying.

Standard resi and commercial voltages.
 
GoldDigger said:
The typical linear fluorescent depends on capacitive current through the glass wall to the reflector behind the bulb as part of the starting process. Use an ungrounded source and such a combination will not work. As for L-L from a grounded system, not sure from the theory side.
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Yes- when a magnetic ballast is involved. For electronic I doubt it for a number of reasons all the way up to taking 277 volt ballasts and running them at 240 in my basement 10 years ago.

However in this case they are LEDs, so it would not (should not) make a difference regardless of driver.
 
electrofelon said:
Can I feed these with 208 from a 120/208 system?
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The output voltage in this case is 36 VDC. The driver determines the input voltage before it goes to a full wave bridge rectifier.
This works like switching transformer that powers the 12vdc and 5vdc in our desktop peripherals.

Whatever input voltage is applied within the range of 120v to 277v is reduced to pre-rectified 36 volts AC (theoretically)...it could be a bit higher to account for loses in electronics. Reducing this input voltage is usually handled by a compact toroidal transformer reduced size compared to E-core laminated transformer.
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The full wave rectifier doesn't care which leg is grounded. The DC output polarity is well established by the DC bridge.
You can try the unit on the bench by switching the input legs (eg neutral and hot)
and they both work either way.
 
For either the fluorescent or LED 85V-285 V ballasts I've disassembled and reverse engineered the circuits , they should make both wires white/black stripes, they don't care as long as there is volts in range between the wires. Both wires are isolated, same insulation, symmetrical circuits in most cases. No safety issues for the ones I've looked at the internal circuits.

I have no idea if Westgate is that way, never have taken one apart.
 
GoldDigger said:
The typical linear fluorescent depends on capacitive current through the glass wall to the reflector behind the bulb as part of the starting process. Use an ungrounded source and such a combination will not work. As for L-L from a grounded system, not sure from the theory side.
Click to expand...

Thanks for that explanation. I always wondered why old floros often state "mount within 3" of grounded reflector" or somethings like that.

Jraef said:
That said, why not just run a hot and neutral (120V) instead of 2 hots for 208V? It's exactly the same number of wires...
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The number of lights I have would be more than 1 circuit at 120V. OF course using a contactor or breaking it up into two switches is possible.

I agree with y'all who think it is likely a non issue. I doubt there is anything like reduced insulation or a ground reference pulled off the neutral , etc.... It would be nice if they would fix this little oversight in their color coding and terminology.
 
We upgraded many of our shop high bay lights with LED retrofit lamps. Bypassed the 400w MH ballasts, connected 208 directly to the Mogul base and they all worked fine. A decent light level upgrade as well. Same 120-277 volt range rating.
 
Depends on who the manufacturer is. Usually these LED ballasts/ driver will not even show the mfg phone and address. Perhaps if you can read or speak Chinese that won't be an issue.
 
GoldDigger said:
The typical linear fluorescent depends on capacitive current through the glass wall to the reflector behind the bulb as part of the starting process. Use an ungrounded source and such a combination will not work. As for L-L from a grounded system, not sure from the theory side.
Click to expand...

GD,I know you know this but for the less experienced, the source could very well be grounded but if the fixture itself had no EG to it or was isolated from ground, the lamps would not start. Dependent on humidity etc. IDK how many service calls we had over the years that the non working fixture would work, the second we touched the lamps. Typically old 2 wire or K&T installs.
 
ptonsparky said:
GD,I know you know this but for the less experienced, the source could very well be grounded but if the fixture itself had no EG to it or was isolated from ground, the lamps would not start. Dependent on humidity etc. IDK how many service calls we had over the years that the non working fixture would work, the second we touched the lamps. Typically old 2 wire or K&T installs.
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Ah, okay I get it.

No EGC, like efelon mentioned a few posts ago about mounting 3” from grounded reflector. I remember those stickers now.

I thought he was saying the new ballasts would not work unless one used a hot and a noodle (grounded conductor).
 
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