JUst moved into a house with this system. The previos owners say it has been out of action for a couple of months.

On inspection it has power going to it because it is still warm on the top of the box. However there are no lights on the panel. I'm guessing the fuses have blown.

Therefore 2 questions.

1. Is my diagnosis correct?

2. Does anyone know the ratings of the fuses in the unit?

Both fuses should be 1.5 Amp, but 1 Amp would do.

And yeah if there`s no lights on the panel then 1 or both are these fuses are probably blown, but before replacing them it would be wise to check for any obvious defects or Short circuits that made the fuses blow in the first place.

Ok

Changed the Fuse that had blown and I had battery power for a couple of hours.

Although the Mains going in is live, The mains light doesnt light up. Is this box for the scrapheap? If so whats the best replacement so I can keep the existing PIR's and Bellbox.

If the system works on battery power but not on mains then it sounds like you might have a fault on the incoming mains feed. I had a problem a few years ago where my mains tester was telling me that the mains was coming in, but neglected to tell me the negative wire had been damaged. It was only after I replaced this customers entire panel and got the same error that I realised their could be a mains fault.