XPS DR Blowing Surge Fuses

Posted by: Alan Willby on 08 January 2017

Just been away for two weeks during which all components were powered down - and actually my dedicated spur was switched off at the consumer unit as well.

In switching everything back on I am blowing the surge fuse in the XPS DR. It does not seem to be the on off switch as on my last attempt I left that on and powered up at the socket with the same result - flash of light from the connection point. So I now have a collection of three blown fuses and not much idea why.

Any thoughts

Posted on: 08 January 2017 by Richard Dane

Make sure the mains lead is all the way into the IEC socket. A loose connection here can blow the fuse. 

You need to get the exact type and make of fuse that Naim supply. Your Naim dealer can get these for you. 

If it still keeps blowing then take to your dealer as it may indicate a fault.

Posted on: 08 January 2017 by Alan Willby

Thanks Richard. I am sure it was not a loose connection as I had not touched the unit - until taking it out to investigate and I was then pushing everything firmly home.

I'll talk to Naim and / or my dealer tomorrow and see what they think.

Alan

Posted on: 08 January 2017 by Ron Toolsie

The xps had a massive circa 850 VA transformer. ..bigger than most 200wpc power amps. ..but due to its relatively low steady state draw it uses a fuse with a lower rating than if it were a power amp...it is not surprising that the current surges are on the edge of the rated fuse values. Even how quickly you turn the switch on can be the difference between a live and a dead fuse.

Posted on: 08 January 2017 by Alan Willby

Thanks all. Never had a fuse blow in 8 years - hopefully it is a minor issue.

Posted on: 08 January 2017 by ChrisSU
Alan Willby posted:

Thanks all. Never had a fuse blow in 8 years - hopefully it is a minor issue.

The XPS has a long standing reputation for blowing fuses, make sure you keep a spare or two just in case!

Posted on: 08 January 2017 by Harry

My old XPS2 ate through fuses. I had a bag of them. I was glad to see the back of it when I traded it in for a 555PS. Every time I powered it up (infrequently) it was like playing Russian Roulette. All perfectly normal apparently.

Posted on: 08 January 2017 by Alan Willby

Yes - I am going to get some today though I am having trouble sourcing the recommended Littel Fuse components. I hope my problem is less than I thought it was. My XPS DR did not have a spare fuse for some reason. The two I blew when trying to sort the issue actually came from my CDX2 (which is of course unpowered when the XPS is in play) and I have now realised these are a lower rating - T1.6AL/250v compared to the required T2.5AL/250v - so no wonder they 'popped'. Hopefully the correct fuse will sort matters out. 

Looking at the fuses it does make you wonder how specialist power cables and dedicated mains spurs can make any difference - they are so fragile looking!

Posted on: 09 January 2017 by Alan Willby

All sorted with new fuses. Cheered me up so I spent some Christmas money on CD's.

Posted on: 09 January 2017 by Harry

Good. Just keep a few spares.