gmod_light turn on and off with metatable

Dear All,
I would like to ask for assistance with communication to a gmod_light entity using meta tables through a gamemode. I would like to control whether it can be turned on and off by a gamemode variable, but I was unable to achieve this using meta:SetOn and meta:Toggle functions. I was successful with thrusters though. I would like to ask for your advice how can I achieve the above.
Thank you very much in advance!