Step 1 : Check if the connection to the main is loose or are there too many appliances connected to the same socket.  Failure could be caused by over current in your mains.

Step 2 : Check the iron's power cord for visible signs of damage (e.g. kinks, flaring of the braiding).  Remove the rest of the appliances and switch it on again. 

Step 3 : if the mains power goes off again, kindly contact a Philips representative for assistance.