I have a corridor application where emergency egress lighting is required. Is there any code-related reason why I cannot wire all of the lights in the corridor to turn on upon loss of normal power to the space using a 20A generator transfer device? The GTD20 will be located above the lay-in ceiling at one end of the corridor and will be fed by 2 separate circuits from two separate panels, one of the panels being an emergency panel fed via the building ATS and the other a normal power panel.
The AHJ is rejecting this design, but I think he is confusing the UL 1008 GTD20 with a UL 924 bypass device, in which case he would be correct. Failure of either breaker will not leave the space dark as the GTD20 will switch if the normal power circuit fails. Failure of any lighting element will not leave the space dark as there are 20 separate light fixtures in the corridor wired via the GTD20. The GTD20 will bypass switching upon loss of normal power so switch position will not impact emergency egress lighting upon loss of normal power to the space. The two circuits feeding the GTD20 are in separate conduits coming from separate panels. The AHJ wants multiple circuits run out to the light fixtures, either alternating fixtures or dual switched fixtures or something similar.
I believe that the two circuits to the GTD20 located in the space meets requirements of NEC 700.17. AHJ disagrees but has indicated he is willing to discuss.
Before I pursue this I wanted to run it by a few others to get opinions/thoughts.