i Did something similar last week at my school...only diffrence is the fixtures were 8 Foot Slimline Stiplights and mounted 15 Feet up,i voluenteered for it...nice job bud.

weird...you sure it was wired correctly?

We have 408 volts at work, scary stuff when something goes wrong!

Yup, it's wired correctly! After I took the pic I carefully inspected the wiring to make sure it was correct.

My teacher, who is a former contractor, told me it's pretty common with those ballasts, at least with that particular brand.

Fluorescent fixtures in that place are *almost* all 347V (between phase and ground). That gives 600V phase-to-phase! I was actually kinda lucky to be allowed to replace it, because I've been told all the 347V wiring is going to be inspected soon, so my teacher prefers not to give replacement jobs to students. But I understand him... some of my classmates are not too meticulous when it comes to wiring. And I guess he saw some who were even worse in the past.

Hey Vince shouldn't you be wearing insulated gloves when working on live 347 volt circuits?

In the pic I wasn't really handling live parts. I wore gloves when I started replacing the ballast.

But starting this year at school, anyone working with live 600V circuits must wear a complete arc-proof suit!

i have wired electronic IS ballasts in parallel with another lamp on the same output leads, same result as here whichever lamp has less resistance starts up, same principle of those standby HPS lamps
i saw the other pic btw of this light

Will wiring it so this occurs hurt the ballast? Will it shorten the lamp life? This is actually a pretty good idea for a fixture! It has two lamps and when one burns out, the next takes over! The only bad thing would be when two identical lamps are used lol.

i dunno, i am less knowledgeable about electronic ballasts ,my guess would be that its not good for it in the long term but i suppose it wouldn't be too hard on the lamp, and would give a backup lamp if one went EOL