The right fuse for a P15

Hello everyone.
I bought a P15 and my local mains are mono-phasic 230VAC. I saw, from the P15 rear picture, that for 230VAC it uses a 3AH fuse even with a maximum continuous load rated at 1500VA. It should need (theoretically) a minimum 6,5 or 7A fuse, shouldn’t?
Am I wrong?
Thanks in advance.

The correct fuse is as per what is written next to the fuse holder


Maybe I was misunderstood or I couldn’t explain it reasonably well, but I DO know that I must use a 3A fuse when connecting the P15 to the 230VAC mains. I simply don’t understand WHY since the maximum load allowed is 1500VA, which corresponds to a ~6,5A current at 230VAC. That’s the point.

Nothing more to think about.
T= slow blow. So you need a 250V slow blow 3A fuse.

Just want to confirm. Is the fuse in the P15 a 5 amp slow blow H-rated 5x20mm?

Mmmm…very strange.
230 x 3 = 690 watt or 120 x 5 = 600 watt.


Just want to confirm. Is the fuse in the P15 a 5 amp slow blow H-rated 5x20mm?

The fuse is identified right above the fuse holder, which on the back of the P15.

Yes, it sure is as long as it’s a 120V unit.

Yes…120V unit. Thanks so much.

And what about the right fuse for a P20? Will it be 5x20mm, slow blow, 6.3 amp?

That’s correct.

My 220-240V input voltage P20s (I have two of them) both have fuses whose end caps are etched with the notation, “T5AH250V”. The silk-screened stencil on the chassis near the fuse cylinder also reads “T5H250V”. These notations suggest that the 5A fuse is the correct one, and not the 6.3A.

Please help clarify, as I’ll be placing orders for the SR Orange fuses soon. Thank you!

I would go for 6.3A if originals are 5A just to be safe not to blow them. Aftermarket fuses have a tendency to break at same A level as original fuses. My Gamut amps have 5A fuses also but they broke when switched on,so I ordered 6.3A and no problem since.

Be sure to order slow blow fuses ,not fast ones.

I mean for a thing that can “produce” 1500 watt constantly.

P20 220-240v - 5A, 250V, Slow, 5 x 20 m
P20 120v - 6.3A, 250V, Slow, 5 x 20 m

I must say - we do recommend using the OEM fuse rating, and just be sure to get slow blows, as this is likely why other aftermarket fuses break upon startup.

Otherwise, maybe the aftermarkets are less tolerable to higher load upon startup with the materials being used? That’s my other best guess.


My P15 is one year old: it cracks loud every now and then, presumably they are heat sinks… Are there any remedies? Has anyone the similar effects? By the way - a main 230VAC fuse blown in the time of the first two weeks. I replaced it (very poor cheap one inside…) with standard but good proper fuse , it works till today. I would be very glad with this great power plant, if not this cracking in every listening session…

I have yet to hear any thermal popping from a P15. I’ve had one in my system for about a year now. I sit about 8 feet away from it and I’ve never heard this. The occasional relay, but never a loud pop.

And chance you could grab a video of it?


thanks for the reply, for your readiness to help. No, I’m afraid I cannot do video: I don’t use a smartphone, over that the popping comes - with some minimal metallic reverb - not regularly, sometime in about 10, 20, 25 minutes, maybe three, four or only two times at the beginning of the session. About an hour later is all OK.

I must say, I switch on and off the P15 also with the back switch for a session, so no continuous work is done. I use it one, two or three hours a day, or a couple of days not at all. I sit very close to P15 and hear with a headphone.

Thank you for your help.