10 ohm 5 watt resistor vs resettable fuse question for Chuck

[DDad]

I see Chuck uses a 10 ohm 5 watt resistor on breadboards for short circuit protection. Is that better than a resettable fuse?
If a resettable fuse is a good alternative to the resistor, what amp value should it be for guitar pedal breadboarding?

 

[Chuck D. Bones]

it's rare that the pedal current is over 100mA, so if you can get a resettable in that range, great. I have some 1.85A resettables, which is kinda high, but still provides sufficient protection. The 10Ω resistor is convenient, I had some laying around and it does the job without dropping too much voltage.

 

[DDad]

Thanks! So if I can't find a lower amp resettable I will buy a 10 ohm 5 Watt

 

[Chuck D. Bones]

Or anything in that ballpark.

 

[DDad]

oh duh. I just realized I already knew the milliamps that many pedals draw, from making sure my power to each pedal had enough milliamps. Many way below 100, some need more. I need to read my questions a 2nd time before posting.

2 more questions -

do these resettable fuses react quickly enough to protect power supply and any components in the path?

would it be a good idea to use both resettable fuse and a 10 ohm resistor? or bad idea?

 

[Chuck D. Bones]

Tough question. Things that die from overheating will probably be protected. Things that die from electrical overstress could die in milliseconds and the fuse probably won't help. The resettable fuse is there to prevent wire insulation from melting, traces from frying, that sort of thing.

You can use the fuse and resistor together, but one will act first and then the other one won't matter. A 10Ω resistor will limit the current coming from a 9V source to what?

Power supplies should protect themselves.

 

[DDad]

A 10Ω resistor will limit the current coming from a 9V source to what?

If I accidentally cause a dead short after the 10Ω resistor, does that mean I can use the formula I = V/R, so I = 9V / 10Ω = 0.9A? 900ma?