Questions regarding physical fuses. Fuses are a safety device consisting of a strip of wire that melts and breaks an electric circuit if the current exceeds a safe level. PPTC, PTC, and Polyfuse questions should use the Polyfuse Tag. Please keep in mind that repair questions are typically closed if ...

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6
votes
1answer
1k views

'Voltage Fuse' or better

I have a power supply with multiple outputs (5v, 12, 24v) According to the manufacture (and after testing) there must be a minimum load on the PSU for it to supply the stated voltages. Without a ...
17
votes
5answers
23k views

Fuses: What are the practical differences between Ceramic and Glass cartridge fuses

What are the practical differences between ceramic and glass tube cartridge fuses? I am trying to find new fuses for a piece of consumer electronics. The original fuses are going out of production. ...
3
votes
5answers
663 views

Why do 0.02A fuses not protect a person? Why no protection from shocks?

I understand the user here so that fuses do not protect people from shocks. I am planning to put put fuses such as fast-blown fuses and PPTC fuses around all kind of positions such as ...
3
votes
2answers
528 views

Designing with fuses…when to use?

Most circuits that I have designed in the past deal with low voltages...sensors, communicating with other chips, etc. When would I need to consider the addition of fuses into my designs? Sometimes I ...
6
votes
2answers
829 views

Short circuit protection for high current wearable: fuse, polyswitch, TBU, circuit breaker, something else?

I am thinking about design elements for a rather high current, battery powered, wearable application. Maximum current of 40A at 5V, but typically around a third to a half of that. Power would come ...
4
votes
3answers
3k views

When should you use a fuse?

When is it actually practical to use a fuse? Like lets say your building a robot using an Arduino.....what area would you want to protect the most with a fuse? I mean do they even make fuses that ...
8
votes
3answers
2k views

Can a fuse be placed after a load?

Considering that the regular treatment of a fuse is to place it on the positive side, "before" a load, is this just common practice, or is it backed by an actual reason? Can a fuse be placed on the ...
3
votes
6answers
15k views

How does a fuse blow at its current rating, regardless of voltage?

I know from reading elsewhere that it's safe to use a fuse with a higher voltage rating when replacing one, so long as the current rating and reaction speed is the same. For example, if a fuse is ...
3
votes
2answers
2k views

Why do PTC fuses have different voltage ratings depending on package size / hold current?

I've been trying to figure out the PTC fuse I want to use in a little automotive power supply circuit and I'm a little disconcerted by the max Vdc ratings most of these things have. For instance, ...
2
votes
2answers
1k views

Should a fuse with the correct amps, but is physically too small, still power my stereo unit?

I'm not sure if I'm asking the right kind of question for this site. But if someone could help me, I'd be grateful: I blew a 125V 2.5A fuse in my home stereo head unit. I couldn't find that fuse at ...
1
vote
1answer
3k views

How do I choose the right replacement fuse for my multimeter?

I have a BK Precision 2709B Multimeter. I managed to blow the uA fuse (500mA/500V fast blow ceramic) on it. Is it an ok to replace this fuse with a 500mA/1kV fast blow ceramic fuse? What impact would ...
0
votes
2answers
75 views

PCB design for automotive fusebox?

I am currently in the process of designing an automotive (motorsport related) fuse-box as a side project to my studies. I've not had much luck searching for fuse holders (20 position) however while ...
0
votes
1answer
530 views

Choosing Fuses or MCB in 24VDC vehicle circuit

I am currently designing a 24VDC circuit for a small vehicle. I personally prefer using MCB's since they are simple to reset and easy to detect faults in the system, although i do find it rather hard ...