Fuses?

[Lee]

So I've heard I need to put a PTC resettable fuse inline on my battery leads... anyone have part numbers/retailers for those?  I'm looking for both 12v and 6v, since I have 2 battery systems I need to protect.

Mucho +T to those who can help me out!

[Nick Culbreth]

i've been lazy and never bothered w/ the fuses but i've been told bournes manufactures them.  check out mouser.com i'm sure you'll be able to find what you're looking for.

[Brian Skalinder]

I don't have part numbers handy, but search www.mouser.com for "resettable fuse".  I think I've used both Bournes and Raychem radial resettable fuses before.  Stay away from surface mount device (SMD) fuses.  Find one with the appropriate specs for your use.  There are basically two specs:  voltage and current.

The voltage is the max voltage spec for the fuse - it's okay if the voltage (V) rating is higher than whatever voltage you're running, just don't get a fuse with a voltage rating exactly equal to or lower than what you plan to run.

The current (A) rating indicates the current specs for the fuse.  Figure out the current draw of the device(s) you want to power and find a fuse for which your current draw is around 50-80% of the fuse rating.

[rabhan]

http://www.marchingant.net/battpack.htm

"PTC Resettable Fuses: For circuit shorting protection you might want to try a PTC (Positive Temperature Coefficient) Resettable Fuse.  Its your option. There are positives and negatives about using circuit protection. Mouser stocks them and they are rather cheap, I suggest ordering a few, they are rather delicate"

[DaryanLenz]

What good are they...I'ver never used them but would this prevent oh say, crossed wires or something from damaging the unit?  If so, post some links.  Does the rat shack have em?  Also, where would one solder this into, as in directly to the terminals or what?

Daryan

[Brian Skalinder]

What good are they...I'ver never used them but would this prevent oh say, crossed wires or something from damaging the unit?  If so, post some links.  Does the rat shack have em?  Also, where would one solder this into, as in directly to the terminals or what?

What good are they...they'll keep your gear from getting fried!  A short which spikes the amperage can damage your gear or cause a fire.  B-A-D.  The fuse will open the circuit when it's amp rating is reached, thereby protecting your gear.  You should wire it to the hot (+) lead.  I use a short wire from the terminal to the fuse, then connect the other lead on the fuse to the wire going to my power plug.  Easy peasy.

I forget which fuses I have, but search Mouser for PTC resettable radial fuse or something close to that.  You want a fuse with an amperage rating higher than the current your gear will pull from the battery.  A fuse where your gear current draw is 50-80% of the fuse's amperage rating should be sufficient.  The voltage rating doesn't matter much as long as it's higher than the voltage you'll be passing through the fuse.

I'm sure there are finer details than these, but I haven't researched thoroughly.  Maybe somebody with EE education/experience can provide more details.

[pnobles]

i use buss atc fuses for my 5v system, i currently use the "E" fuse, it is purple.  i am not sure if this is the correct one but it has worked well so far. ( i just blew it yesterday while adding another 4pin to my battery )

anyone know the correct fuse i should be using?
thanks

[barren4]

http://www.marchingant.net/battpack.htm

"There are positives and negatives about using circuit protection.

Would you mind elaborating on the negatives of circuit protection in our application?  Dependablity?

[leegeddy]

i use buss atc fuses for my 5v system, i currently use the "E" fuse, it is purple.  i am not sure if this is the correct one but it has worked well so far. ( i just blew it yesterday while adding another 4pin to my battery )

anyone know the correct fuse i should be using?
thanks

you should check your manuals for "Current Consumption" or "Power Consumption".  add your current draw values to gether to get an idea what is the total current you are drawing from your power supply.  this will give you an idea what size fuse you'll need.

most of these electronic devices we use (DAT, pre, A/D) draw very little current (amperes) and are in the factor of mA (milliamps).  if you see the spec in "Power Consumption" in Watts, divide that number by the operating voltage to get amps (P=amp  X voltage).

my Beyer MV-100 pre draws approximately 85mA with Phantom Power "on".  since that's the only current drawing load, i'm using a 100mA inline fuse from Radio Shaq.  i've yet to blow a fuse and keep few spares in my bag.

marc

[zhianosatch]

What good are they...I'ver never used them but would this prevent oh say, crossed wires or something from damaging the unit?  If so, post some links.  Does the rat shack have em?  Also, where would one solder this into, as in directly to the terminals or what?

Daryan

BOOOOOOOOOOOOOOOOOOOOOOOOM

[pnobles]

on my previous post, i said i use buss fuses for my 5v system...that should read 6v system...duh...sorry