How much does it cost to replace a fuse?

[chaskuss]

Originally Posted by Kahuna

A 5 amp was called out by stark when I Installed it.
I guess its 10 now.
5 amp made it 200 hours
Looking at the specs, page 1-3 rev L of the 400 series manual, it is 6amps at 13.75 volts when transmitting. So there you go.

And no there is no way of knowing. There are multiple power inputs for the nav and com on a 430 for redundancy. It looks and feels like it is working if the com fuse is out.

Mike,
I admire your guts for even admitting this tale on list. I just want to remind you that the 10 amp fuse requires heavier gauge wire than the 20AWG required for a 5 amp load. You need 16AWG wire to ensure that a short in the radio will blow the fuse before the wire heats up to the point where it catches fire. Did you upgrade the power wire when you upgraded the fuse? Perhaps all you really need is a 7.5 amp fuse? (18AWG)
Charlie Kuss

[SteinAir]

FYI...we're going to start stocking some really neato blade fuses that have a little light built onto the top of them that illuminate only when the fuse is blown. We have some, but not all the amperages yet (hence them not being on the website yet), but when we do they'll be available on our website. If you're at OHS, stop by our booth and you can see what some of them look like (before and after they've been blown). They light up really nice and bright after the fuse blows to let you easily see when one is popped!

Cheers,
Stein.

RV6's, Minneapolis.

[kevinh]

Originally Posted by SteinAir

They light up really nice and bright after the fuse blows to let you easily see when one is popped!

Sounds cool! How do they work? Does the heat of the fuse burning change the color of a dye or is it electric?

If electric, where do they get their path to ground? Does it rely on a small amount of trickle through the nominally disconnected circuit?

Just curious...

[gmcjetpilot]

Originally Posted by chaskuss

10 amp fuse requires heavier gauge wire than the 20AWG required for a 5 amp load. You need 16AWG wire to ensure that a short in the radio will blow the fuse before the wire heats up to the point where it catches fire. Did you upgrade the power wire when you upgraded the fuse? Perhaps all you really need is a 7.5 amp fuse? (18AWG) Charlie Kuss

I agree a 7.5 amp would be a nice choice.

I do agree 20 awg and 10 amp fues would not be my choice. The FAA best practice "AC" also agrees with what you are saying, calling for a max 7.5 amp circuit breaker or 5 amp fuse with a 20 awg wire. However......... it is "Best Practices" and there is some margin there.

A 20 awg wire is rated at ultimate or max chassis current rating is 11 amps (short length, not in large bundled) and fusing current is approx 58 amps! (By short length lets say about 6 feet, and large bundle is one where you can't see all the wires easily.)

A 20 awg wire can carry 11 amps without worry of fire. Lets say you ran a 9.9 amps continuous current, and the fuse does not open. The wire would get to 48F degrees above ambient (let's say 120F-140F). That's HOT but still not unsafe. The voltage drop is about 0.61 volts. That's beyond my design criteria for any one's comfort, but we are talking about an inadvertent short, not intentional power transmission.

I do agree 7.5 amps would be best, more comfortable. All my 20 awg wires are protected with 5 amps or less.

So I agree, but to say you must increase the gage is a design decision and not an absolute must. However I am with you, 18 awg is plenty for 10 amp fuse for under the panel wiring. You suggest 16 awg, but that's overkill in my opinion unless the run is real long. Cheers Big CK

[Kahuna]

Yes it was a 7.5 that I put in.
The wire is an 18ga for 8"