I would like to ask OP what sort of "photo-cell" he is actually using.
It could be that the photo-cell is either set up in the wrong mode or the sensitivity level is set wrong, these things are not "plug and play".
At the end of the day all these things are is a voltage in through two terminals and a single change-over contact on the output (NO/NC), with a common terminal
Last edited by Trumpy; 03/10/18 12:08 AM. Reason: Added last bit.