How to tell if lights are 120 or 277

[a1953mdl]

Noob here and with a noob question.
Short of the panel being marked, is there a easy way to visually tell if a light fixture is 120 or 277?
This is in a commercial building and the lights are in an area where it would be difficult to pull the cover and see which voltage they are. Panels are not marked.
I obviously am not an electrician. I have searched this and in searching found your forum has the most knowledgeable people, so thought I would ask here.
Thanks

 

[charlie b]

I am closing this thread, in accordance with the Forum?s rules. This Forum is for professional electricians, inspectors, engineers, and other members of the electrical industry. I am afraid you are going to have to look elsewhere for assistance.