Polarities on Fuse Holder?

[DFliyerz]

I'm doing a project that uses a RadioShack panel-mounted fuse holder, and although I know this is a dumb question, I want to make sure; which tab is negative and which tab is positive?

 

[davenn]

Hi there
welcome to EP

neither of those options

both are negative or both are positive, depending on if the fuse is in the negative or positive rail

cheers
Dave

 

[davenn]

to explain further why your 2 options wont work ....

If you connect negative and positive to the fuse holder ( regardless of which way around) you will create a short circuit across the power supply
when the fuse is inserted and the fuse will blow immediately

so tell us more about your project

are you using DC or AC ?

Dave

 

[KMoffett]

Fuse holders don't have positive/negative polarity. They are placed between one side of the power source and the load. With that holder, the power source would be connected to the end terminal and the load would be connected to the side terminal. The concept is the same as with light sockets, the power source terminal is placed furthest from the user to minimize the likelihood for the user touching the powered contact.

Ken

 

[Fish4Fun]

Hrrrrmmmm, well both tabs should be one or the other, lol. A fuse is a series connected device and you can choose to place it between the positive terminal and the device or between the negative terminal and the device...generally one would place a fuse in the "ungrounded" path so that unintentional grounding will "blow the fuse".

Fish

 

[KrisBlueNZ]

Fuses and fuseholders aren't polarised, but as Ken said (though he got it the wrong way round), there may be a right way and a wrong way to wire it, if the fuse is connected in line with the mains (line) voltage or any dangerous voltage.

If it is, connect the incoming voltage to the side contact. Then, when the user fits the replacment fuse and pushes it into the fuseholder and it makes contact with the spring at the end, the fuse will not be live and he will not get a shock. The live part makes contact with the metal on the inside of the screw-on cover, and that's insulated, so you can't touch it.

 

[Neal]

The fuse holder cap actually is made to retain the fuse in the cap, at least that's the way littlefuse makes theirs. So the fuse is withdrawn when the cap is unscrewed from the holder.

 

[KrisBlueNZ]

I've seen both types, but in either case it's possible to put the replacement fuse into the holder first and that's where the danger lies. At least, that's how it seems to me. I haven't seen a fuseholder where the front contact can be touched by the user; it's only ever the back spring contact that can be touched through the fuse itself.

 

[davenn]

agreed, Kris

 

[Arouse1973]

I've seen both types, but in either case it's possible to put the replacement fuse into the holder first and that's where the danger lies. At least, that's how it seems to me. I haven't seen a fuseholder where the front contact can be touched by the user; it's only ever the back spring contact that can be touched through the fuse itself.

Yep I agree with that Kris.
Adam