Minecraft Setblock Lever - On Position
Solution 1:
The metadata value of the block determines both the direction the lever is facing as well as whether it's on or off. To "set bit 8", you simply add 8 to the metadata value:
For example, a lever facing east that is off:
/setblock ~ ~1 ~ minecraft:lever 1
And a lever facing east that is on:
/setblock ~ ~1 ~ minecraft:lever 9