Although the bulbs are too big wattage wise it wouldn't blow the fuse.I suspect the fuse blew when the old bulb failed or you have done something drastically wrong when fitting new bulbs.If its been installed correctly somewhere there should be a 3A fuse.this will be in a switched spur outlet on the wall or it will be fitted with a standard plug with a 3A fuse in there.look on top of units around extracter and can sometimes be hidden inside chimney flues!
ck, January 2010