Quote Originally Posted by PharmaCan
Mr. C, E = "Earth" aka "ground".
Thanks PC. When I was doing work on electrical equipment, observation and repetition was how I learned not to kill myself, and like then, I didn't pay very close attention to his wiring diagram. I also thought Algag was referring to a single main wire coming from the ballast to the light being labeled as "E" on the diagram. My misunderstanding.

Algag: I'm glad to hear that it's working, but if it will only work when the ground is unplugged, PharmaCan is right...there's something wrong. Did the ballast and lamp/reflector come together, or did you purchase them separately? The reason I ask is because you definitely shouldn't try powering a 400W lamp with a 600-1000W ballast. It might work temporarily, but you'll be overloading the wires going to the socket, and will likely burn the lamp out extremely prematurely, or even worse, frying the connection from the ballast to the lamp & possibly setting your house on fire.

If this isn't the case, then does the electrical outlet being used accommodate a grounded plug? I can't get a clear picture of the colors of your wires, but they look to be connected in the right spots. You might want to think about getting a pair of wire-strippers, and reconnect each of your corresponding wires using individual crimp-connectors. Maybe one of your connectors is faulty. If you're able to disconnect the ground and the light powers up, that means there is not a ground being used to divert the path of the current should an overload occur. Do you live in an older house? Some older model houses didn't require electrical grounds to be placed on all outlets, which is a standard procedure now.

Either way, I wouldn't run that light without a connected ground. I couldn't sleep knowing there is a potential disaster burning bright in my grow room.