XPS2 blown fuses becoming a pain

a correctly designed/type of fuse should not  time after time blow for no reason. it is sensible to switch on power supplies staggered to all units  to settle.  my large mono power amps have never blown a fuse on switch on /off ever...

Phil Harris posted:

Hi,

If your XPS is continually popping fuses then I'd get your dealer involved and get them to check it out - it could be that it has developed a fault and actually is correctly blowing fuses.

Best

Phil

Thank you Phil, however, my XPS2 has always done this, since new.
I suspect the remote location of my home (in the sticks) might mean the incoming mains is at the low end of "normal" and perhaps that might be having an affect.
My dealer was originally involved and the unit was serviced by Darran at A-Class only a matter of months ago.
I shall try a different source of fuses as I was a little alarmed that the glass on one actually shattered and the second one I tried blew immediately too.
The 3rd fuse worked fine but it's always a worry every time I turn on everything after being away.
The unit is currently working just fine.

Richard Dane posted:

blythe posted:

Richard Dane posted:

SWS, are you using the exact same fuses specified by Naim? It may be worth a word with Steve Hopkins to see whether he can send you some. 

FWIW my own XPS2s only blew a fuse once and that was down to me not having the mains lead connected all the way in to the IEC socket. Worth checking there's no arcing going on in there...

As the originator of the thread, perhaps you were asking me about the exact same fuses specified by Naim?
When I bought my last box of fuses (yes, I buy them buy the box full) I spoke to Naim who advised the correct rating and then, I bought them on-line.
It's possible of course that my source of purchase was subject to on-line vagaries and begs the question, was I actually buying the correctly rated ones...?
Richard, are you able to post the correct rating for the 240v XPS2 unit here?
By ordering a batch from a reputable supplier such as RS Components, that'd help me rule out "dodgy under specced fuses".
Thanks, Martin.

Blythe, best get Naim's recommendation on this.  I'm a bit reluctant to post here, mainly because it's an international forum and specs are different depending on where you are and the local voltage supply, and I would hate to be wrong.  With that in mind, from memory, the UK supplied 230V XPS2 uses a 2.5A T fuse from The Littel Fuse Company, but I would recommend double checking with Naim on this.  I don't know whether Naim test their batches or not, but may be worth finding out.

Many thanks Richard - I'll contact the Little Fuse Company - 2.5A T fuse is exactly what I currently use - I wanted to be sure I hadn't inadvertently ordered the wrong thing altogether...
I will naturally absolutely confirm the exact UK fuse spec with Naim.

I’m going to regret this but my XPS2 is 14 years old and has had one recap. It’s powered down 3 or 4 times a year and has yet to blow a single fuse

Now, watch it blow!

I've had my XPS2 for 13 years and it's only once blown a fuse and that was the result of a power surge/cut. In fact on that occasion every piece of kit blew it's fuse.

I wouldn't be happy owning the unit you have.

Mike Hughes posted:

I’m going to regret this but my XPS2 is 14 years old and has had one recap. It’s powered down 3 or 4 times a year and has yet to blow a single fuse

Now, watch it blow!

Having looked up my original purchase invoice, it turns out mine is also 14 years old!
I only power mine down 3-4 times a year and it blows almost every time... I guess it's possible that mains quality comes into play to some degree and, me being out in the sticks might make a difference.
My latest fuses blowing, I suspect could be due to the replacements I bought on-line. (Possibly not slow blow but I can't be sure).
I have now just ordered some replacements made by the Littelfuse Company (I spelt it incorrectly above) from RS, to the specification recommended by the nice people in Tech support. (Thank you Phil & Steven).
Hopefully, these will stand power up better than my current lot of fuses. It's likely to be next year before I need to power down and up again though!

blythe posted:

"A brand new fuse never blows on it's first power up"?
Mine did !

Interesting, it has not been my experience and I have got through quite a lot of fuses over the past 7 years.

all fuses will deteriate over time/years mainly due to oxidation and the heat cycle of fuse/tension of the fusing element.,fuses should not continue  to blow as explain above.  it is vaguely possible the the ambient temperature around the fuse carrier is a cause of failure.  my guess is that the contact of the fuse carrier is not flush with the fuse which could cause a problem at switching

..Or, as I believe I explained above, it's possible that the last batch of 10, which I bought on-line, might not have actually been fully to spec.
There are different "series" of seemingly the same Amp and Voltage slow-blow fuse. (So I have found out.)
I have now purchased some "Littelfuse" Company ones from RS, the precise model suggested by Naim Technical support. 
Even with "Littelfuse" fuses, their 250V T2.5A appear to be available in several "Series". Naim recommended I buy the "Series 213".
Next time I power down and up, if the fuse blows, I'll try one of these new Littelfuse ones instead :-)

blythe posted:

Even with "Littelfuse" fuses, their 250V T2.5A appear to be available in several "Series". Naim recommended I buy the "Series 213".
Next time I power down and up, if the fuse blows, I'll try one of these new Littelfuse ones instead :-)

That's a fair point although, the fuses might be deemed "consumables" just like light bulbs for example....
I'll let you know how I get on but, as I'm not in the habit of switching off for the fun of it, it may be quite some months before I need to re-power!