I am building my own power supply with the Weber WPDLXFMR-1 transformer (8 11vac windings and 1 9vac winding). I would like to use a fuse in the 120v portion of the circuit for safety. Any suggestions on the fuse that I use for this project?
Thanks,
Scott
What fuse to use for DIY Power Suppy
- PokeyPete
- Resistor Ronker
I let a day go by hoping someone more articulate than me would answer your question.
But, since no one has, I'll take a stab at it.
We know that P=IE......Power (watts) = I (current in amps) X E (emf in volts)
If the 120 volt primary were supplying 1 amp of current, it would be producing 120 Watts.
Let's see how much it is having to support in this case.
The secondary has a winding providing 11 volts @ 300 mA (.3A)....using the P=IE formula
that works out to be 3.3 watts. Since there are 8 of these windings the total of the eight
11 volt windings would be 26.4 Watts. Now add the 9 Volt winding @ 2A and that's another
18 Watts bringing the total secondary Watt count to 44.4 Watts.
This is far less than what is needed from the 120W that a 1A fuse on the primary would provide.
In fact a .5A fuse would cover 60 Watts. Now there are core losses needed to be taken into
account, but since I doubt that you will be maxing out each secondary winding (in fact I think
most pedals use well under 100mA of current), I think that you would be safe using a 1/2A fuse.
PP
But, since no one has, I'll take a stab at it.
We know that P=IE......Power (watts) = I (current in amps) X E (emf in volts)
If the 120 volt primary were supplying 1 amp of current, it would be producing 120 Watts.
Let's see how much it is having to support in this case.
The secondary has a winding providing 11 volts @ 300 mA (.3A)....using the P=IE formula
that works out to be 3.3 watts. Since there are 8 of these windings the total of the eight
11 volt windings would be 26.4 Watts. Now add the 9 Volt winding @ 2A and that's another
18 Watts bringing the total secondary Watt count to 44.4 Watts.
This is far less than what is needed from the 120W that a 1A fuse on the primary would provide.
In fact a .5A fuse would cover 60 Watts. Now there are core losses needed to be taken into
account, but since I doubt that you will be maxing out each secondary winding (in fact I think
most pedals use well under 100mA of current), I think that you would be safe using a 1/2A fuse.
PP
“No man is so foolish but he may sometimes give another
good counsel, and no man so wise that he may not easily err
if he takes no other counsel than his own. He that is taught
only by himself has a fool for a master.”
–Hunter S. Thompson
good counsel, and no man so wise that he may not easily err
if he takes no other counsel than his own. He that is taught
only by himself has a fool for a master.”
–Hunter S. Thompson
Thanks PokeyPete!! I appreciate the education. Always looking to learn.