| Electronics > Beginners |
| DMM amp fuse question |
| << < (3/3) |
| Neilm:
--- Quote from: haizaar on August 02, 2019, 02:44:04 pm --- Now I understand "IR 10kA" meaning - it means that above 10kA the fuse will explode, or create an arc, etc., i.e. will not terminate the current safely, right? --- End quote --- Your understanding is not quite correct, the 10 kA means the fuse is rated to interupt a fault current of 10 kA. --- Quote ---Still my question remains. I'll rephrase it: taking the spec you linked to as an example: * At 200% of 20A it will open in between 150ms to 5s. Even on 1V? I.e. if I connect it to lab power supply that will output 1V and unleash 40A current, will it open? --- End quote --- Voltage has nothing to do with how fast a fuse will open except that it will generate more current through that fuse. As the fuse is designed to open when the fuse element gets hot enough to burn out this is calculated for a specific current flowing through it. The fuse will have a voltage drop across it as the fuse wire in the cartridge does have some resistance, but this resistance changes as the fuse heats up and in most cases is irrelevent to the designer who has specified the fuse. The voltage rating on a fuse says how much voltage can safely be applied across it when the fuse has opened. So to answer the question if you do put 40 A through your 20 A it will open. |
| Navigation |
| Message Index |
| Previous page |