- #1
George317
building a DC supply with a load voltage of 3.3V and load current of 3.3mA.
all the books and schematics I'm seeing is that they're putting the fuse in the primary of the transformer, why?
if i were to fuse the primary as well how do i get the rating of the fuse that i'll need? its said in my book that Ifuse=Pload/Vrmspri
but if i do that then I = 3.3mA(3.3V) / 220 = 49.6uA(in my country we use 220Vrms), isn't that quite small of a current rating for the fuse considering I'm going to put it in the primary of the transformer which has super high voltage.
also side question what is the ampere rating that i see in the secondary of my step down transformer? in my transfoer there's 12V -0-12V then above it there's 1 Ampere written. does that mean my transformer produces 1A in the secondary?
tnx
all the books and schematics I'm seeing is that they're putting the fuse in the primary of the transformer, why?
if i were to fuse the primary as well how do i get the rating of the fuse that i'll need? its said in my book that Ifuse=Pload/Vrmspri
but if i do that then I = 3.3mA(3.3V) / 220 = 49.6uA(in my country we use 220Vrms), isn't that quite small of a current rating for the fuse considering I'm going to put it in the primary of the transformer which has super high voltage.
also side question what is the ampere rating that i see in the secondary of my step down transformer? in my transfoer there's 12V -0-12V then above it there's 1 Ampere written. does that mean my transformer produces 1A in the secondary?
tnx