By the way,
@JohnYang1997
Hope you can solve my problem,
Sorry is gonna be a bit long below
But i wish i can explain the whole situation clear for you so maybe you can clear my doubts.
My A90 already experienced fuse burnt for many times when turning on the device using back switch,
I see the stock fuse was using F500mAL 250V Fast Blow
So when i first blew the first fuse, i replaced with the spare one, and it blew less than 24 hours
So i ordered multiple Fast blow 500ma and replaced ( Fuse Eatonn Bussman BK GMA 500R)
After installed. it blew all right away.
Then i come research for the internals image of A90 here and i found it use the Meanwell IRM-20-15 which can be seen in above user posted image.
Input
100 240 VAC 0.6A 50/60Hz
277VAC 0.3A 50/60Hz
My country is 240V, and i checked my house range between 239V - 245V at different days, hours
Also tested at other different location as well
So my question here is
if following above Power supply specs 240VAC 0.6A, used by A90
should'nt the fuse used be at least or higher than 0.6A?
while A90 currently using 500mA fuse?
After blowing many 500mA
i contacted my Seller and he contacted with Topping technician (i hope it is)
The technician recommended me to try higher ampere rating fuse up to Fast blow 1A as they suspected voltage surge or spike.
and said A90 is safe up to T1.0A slow blow fuse.
So i tried 750mA and 1A fast blow
And it blew all the way up to 1A,
750mA blew straight away after installed and turn on,
1A blew after 10 hours of use, which the A90 still usable like normal before i turn off and went out for meal and came back turn on again and it blew.
Then now the technician recommend me to try T0.5A Time Delay or Slow Blow fuse,
currently still using and have not experience any blow yet.
and is not just me who experienced it, another customer of my seller experienced the same issue as me as well after getting the A90 and only used few times and not even burnt in. My unit i used more than 150hours before i experienced this issues.
Do you think my unit is fine? Tried to claim warranty due to worried some internal parts are faulty but they would'nt accept unless the A90 completely failed to turn on even after changing higher fuse ampere rating.
So the two most important concern is
1) Is the fuse used in the A90 (500mA) a bit under ? since the Meanwell PS input rated up to 0.6A at 100 240VAC.
2) The stock fuse is Fast Blow/Fast Acting type, should it be standard install with Slow Blow/Time Delay type if A90 is sensitive like that?