Hi All,
I'm sorry if this has come up before but I did a quick search and didn't see a definitive answer. I have a decent electrical understanding but I have no idea of the setup over the pond.
I purchased a mesa boogie 50:50 power amp second hand in the UK. The amp runs on British/European voltage (around 230V AC) and the line fuse and the spares that came with the amp are rated at 1.5 A, 250 V.
The manual and the sticker on the fuse holder say that the required fuse is 3A.
Now, my knowledge of fuses is that they blow at a specified current and NOT power and therefore the current that they blow at should be independent of voltage. If this is correct then a 3 A fuse should be used irrespective of the line voltage. While I know fuses can be rated at different voltages I believe this is simply the maximum rated voltage at which the circuit can be safely interrupted by the fuse (i.e. no arcing).
On the other hand, for a constant power, a european unit should draw less current due to the higher voltage? Or does this not matter, has it already passed through the transformer and therefore should be the same?
Someone told me that the majority of fuses sold even in the US have a rating at 250 V, is that correct? I suppose the reasoning is that it is safe to use a fuse rated for a higher voltage and it is easier to manufacture the same fuses for use worldwide. I did find a couple of posts on this forum suggesting that different fuses should be used for European voltages but my instinct is that they are incorrect. Does anyone know for sure how this works?
If the correct fuse is in fact 1.5 V then I find it strange that the sticker is incorrect as the stickers for the voltage on the back are correct, I have no reason to think it was a US model converted over.
While I know using a lower rated fuse will not cause any damage to the unit I don't want it to blow unnecessarily either due to being too low. Should I change it to a 3A fuse?
Cheers ,
Ell
I'm sorry if this has come up before but I did a quick search and didn't see a definitive answer. I have a decent electrical understanding but I have no idea of the setup over the pond.
I purchased a mesa boogie 50:50 power amp second hand in the UK. The amp runs on British/European voltage (around 230V AC) and the line fuse and the spares that came with the amp are rated at 1.5 A, 250 V.
The manual and the sticker on the fuse holder say that the required fuse is 3A.
Now, my knowledge of fuses is that they blow at a specified current and NOT power and therefore the current that they blow at should be independent of voltage. If this is correct then a 3 A fuse should be used irrespective of the line voltage. While I know fuses can be rated at different voltages I believe this is simply the maximum rated voltage at which the circuit can be safely interrupted by the fuse (i.e. no arcing).
On the other hand, for a constant power, a european unit should draw less current due to the higher voltage? Or does this not matter, has it already passed through the transformer and therefore should be the same?
Someone told me that the majority of fuses sold even in the US have a rating at 250 V, is that correct? I suppose the reasoning is that it is safe to use a fuse rated for a higher voltage and it is easier to manufacture the same fuses for use worldwide. I did find a couple of posts on this forum suggesting that different fuses should be used for European voltages but my instinct is that they are incorrect. Does anyone know for sure how this works?
If the correct fuse is in fact 1.5 V then I find it strange that the sticker is incorrect as the stickers for the voltage on the back are correct, I have no reason to think it was a US model converted over.
While I know using a lower rated fuse will not cause any damage to the unit I don't want it to blow unnecessarily either due to being too low. Should I change it to a 3A fuse?
Cheers ,
Ell
