3 way switches and emergency lighting

[toadysanchez]

Hello Forum!
The building I maintain has some fluoro fixtures with battery backup ballasts. There is a 3-way switch at each end of the hallway. We've noticed that when a switch is thrown some fixtures turn off, while other fixtures go into emergency mode (loss of power). These fixtures work by needing a constant hot from the breaker (which keeps the battery charging and informs the backup of a loss of power) and then a switched hot for the lamp so the fixtures can be turn off when not in use. In the event of a power loss (simulated by de-energizing the breaker) the fixtures switch to battery power. I won't go into what I'm seeing in the pull boxes but I'd love it if someone could let me know how to properly wire this.
My guess is that the branch circuit splits prior to first switch or fixtures and part continues through to all the Line circuits and the other splits somewhere to hit 3-way switch #1, then a carrier to #2 then a return to #1.
Appreciate any thoughts.
thanks
ts

 

[westward10]

It isn't uncommon to see this issue. Wire them as normal then take the permanent hot from a suitable point which could be an unswitched hot from the switch, test facility or the breaker.