Are you sure you want to delete this?
Thanks Mike - If I may just add to the above, if Lucas is working between two phases on a three-phase supply, the resultant effective voltage (RMS) is not two-times 120V. Your multimeter may be showing you a value of 240V between the two phases, but that is the peak value will not be the true RMS value (root-mean-square) as you are (normally) getting two separate 120V supplies that are 1/3 of a waveform (120 degrees) out of sync with one another.
You can look up the mathematics on Wikipedia - it's all fairly straight-forward. Look-up the terms root-mean-square, three-phase and electrical ballast.
I do not know what type of ballast the lamp is using (and the word 'Ballast' covers a multitude of sins and devices used to limit current and otherwise control the electrical supply, each different!) so I cannot tell Lucas what if anything will be the damage done.
Knowing this stuff is bread-n-butter to any qualified gaffa, but even they, in times of a need to improvise, would never, I hope, try to put a light between two phases. As stated above - I've seen it done and the results were interesting, dangerous and very nearly deadly!Back to Lighting...