On January 3, 2013 at 19:27, Lyndel McGee said...
The first thing you can do is to try temporarily shorting the ends of the fuse with a small wire and if the DS lights show dimly, the DS is still good.
Good advice. I wil doe that.
By the way I got another DS (with a RU 990) and I could load my other RU990 / TSU7500 with it, too, without any problems.
So I have two faulty DS and it could be the fuse. But what could have caused it ?? - at the moment a theoretical question.