Bussie, first a couple of questions for you to answer.
Please state the type of 18W lamp you have, are they compact lamps, 600mm standard lamps?
Secondly, if they are compact how do they connect to the base? E27 Screw, B22 Bayonet, 2Pin TL-C, 4 Pin TL-C (These can be TL-D's as well), 2 Pin U lamps or 4 Pin U lamps?
What is the manufacturer of the control gear? Model number etc.
The reason for this is that different lamps connect differently and different manufacturers use different connection methods depending on the lamp type, rating and type of control gear, standard, Hi Frequency, Hi Pot Ballast or Emergency