I am replacing it in a UPS back up energy for my computer.please if you dont know dont answer, dont guess.
yes you can, 1 amp wont hurt it at all. just do it in a static free area.
Theoretically speaking yes you can. Would it work yes it will. Will it be a healthy system I believe not. The reason is: A 5 AMP fuse can absorb more current spike before it blows up then a 4 AMP fuse. There fore it will blow up much later then the 4 AMP fuse which might cause the breakdown of your system. Another good reason why I would recommend against it is: Your circuit resistance and all electromagnetic properties are well calculated with in the original engineering of the system. If you change a component in this case increasing the AMP on a fuse will cause an increase in the resistance of the circuit. Now depends on what the circuit does and what it sets out to achieve, that change will definitely change the way the circuit transfer current and voltage.
