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LED parking lot fixtures are rated 100-250 volts and the wiring diagram shows the blue wire to neutral. To use 240 volts in the US (across 2 hot wires):), can I put the blue wire to the other hot for 240 volts?
 

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LED parking lot fixtures are rated 100-250 volts and the wiring diagram shows the blue wire to neutral. To use 240 volts in the US (across 2 hot wires):), can I put the blue wire to the other hot for 240 volts?
Yup.

For 120, brown on hot and blue on neutral.
For 230, brown on L1 and blue on L2.

All this assuming the fixture is, indeed, rated for either voltage.
 

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Just did a bunch of RAB's, and their driver required a neutral. Didn't care if it was 120 or 277, it just had to have a neutral (ground). It worked on 208, for awhile.
FWIW
It may be related to the voltage above ground on the one leg. the dielectric stress between ground and the leg that should be neutral is near 0 volts but if you hook it up to 208 volts there is 120 volt difference between the enclosure and 1 leg.

Actually that leads me to the question. if the equipment is rated from 100 to 240 volts why would you connect it 208 volts instead of 120? Are there actually that many drivers connected to the branch circuit that you need 208 volts or is is just because the Europeans used 240 volt connection, remembering that at 240 volts 1 wire is grounded so only a few volts from ground ever is impressed on that side of the circuit.
 

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It may be related to the voltage above ground on the one leg. the dielectric stress between ground and the leg that should be neutral is near 0 volts but if you hook it up to 208 volts there is 120 volt difference between the enclosure and 1 leg.

Actually that leads me to the question. if the equipment is rated from 100 to 240 volts why would you connect it 208 volts instead of 120? Are there actually that many drivers connected to the branch circuit that you need 208 volts or is is just because the Europeans used 240 volt connection, remembering that at 240 volts 1 wire is grounded so only a few volts from ground ever is impressed on that side of the circuit.
When it comes to lighting running higher voltages has an advantage. More fixtures and less voltage drop. This is the reason why interior lights are usually only available in 120 or 277 as apposed to exterior lighting which frequently comes in 208, 240 and 480volt options as well. When I see 208 or 480 its the first thing I grab.


Im wondering if that had something to do with it. Ive seen LED driver connected phase to phase but I wonder if all are designed to.

Anyone know?
 

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When it comes to lighting running higher voltages has an advantage. More fixtures and less voltage drop. This is the reason why interior lights are usually only available in 120 or 277 as apposed to exterior lighting which frequently comes in 208, 240 and 480volt options as well. When I see 208 or 480 its the first thing I grab.


Im wondering if that had something to do with it. Ive seen LED driver connected phase to phase but I wonder if all are designed to.

Anyone know?

Yes in Canada we use 347 volts rather than 277 so we can put a lot of fixtures on a commercial lighting circuit but LED have such little current draw I just don't see a reason to put a lot of LED in at 208 volts.
in North America, 208 volts or 240 volts does not have a grounded wire. both wires are 120 volts to ground. In Europe a 240 volt circuit 1 wire is 240 volts to ground and the other is 0 because it is grounded. If the power supply case is metal the case will be at 0 volts but both wires are 120 volts higher so of it is intended that there be a neutral at 0 volts difference from ground the driver may fail here at 240 volts but be fine in Europe.

Many electronic circuits reference ground so if the reference is intended to be 0 volts to 1 wire and it is 120 volts the driver may fail prematurley. In N America if a power supply is intended for 208 or 240 it is built differently than in Europe.
 
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