Hello everyone. I'm new in the forum. I have to solve an electrical problem in a housing complex and I turn to you for some help. The complex is divided into two sectors, which each has 8 departments, 16 departments in total. What I want to solve is the following: The stairs sector (middle part) has a luminaire connected to a photocell that is located on the Central board located outside the complex, in turn this photocell controls the external luminaire of each module On cloudy days, in the stairway sector there is no light, nothing is visible, and there is no key to operate the luminaire without the exterior lights being turned on (I do not understand why they did not divide the sectors) How can I do to give power to the luminaire of the staircase sector, and that in turn, if the photocell gives the order to turn on all the lights (exterior and staircase sector), no electric core is produced. I also don't want to modify the electric lines, nor divide the sectors, because the complex is relatively new, but apparently they didn't do things very well. Thank you

Good as nastor tells you. Use a 220v coil relay and single or double inverter of 10 A. In any large electronics or electricity house you will find it, for example. Here in Rosario Rosasario sur electronica you have it, I use it to combine 2 faces in cuts of, current in electronic equipment.

Hello I recommend that light on stairs independent of the central photocell and control either with buttons plus timer, or with presence detector (recommended) or with another photocell located elsewhere Discuss which option you prefer