Hi to all those who were interested my Tri-Spark was replaced. It was reprted that the unit was dead on arrival. The potting compound was removed and was then tested again and it seemed to be perfectly OK. I have the replacement here now. One intersting point is that the potting comppund is now blue my old unit had black. Very pleased with the service I received. Maybe someone on the forum can comment on the potting compound and if the change in colour means a different type of compound is being used? (I have n experience of potting compounds)