what fuses to use - instrument panel?

[Graham]

Hello, I've recently replaced all my gauges on a C&C30 sailboat to with ISSPro gauges (Oil Pressure / Temp / Volts / Gass). I do not know what fuse I should use to the main ignition switch and then the 4 fuses to use going to each gauge. Is there a good standard of practice here?

This is the style of gauge I'm using: http://isspro.mybigcommerce.com/r8620/

Thanks!

[edwardc]

Contrary to popular belief, the fuses are there to protect the wiring, not the devices. The fuse should be sized according to the smallest gauge wire that is in that particular circuit. Its ok to go smaller, but never larger.

Typical sizes are:
12 awg 20 amps
14 awg 15 amps
16 awg 7.5 amps

[Graham]

Contrary to popular belief, the fuses are there to protect the wiring, not the devices. The fuse should be sized according to the smallest gauge wire that is in that particular circuit. Its ok to go smaller, but never larger.

Typical sizes are:
12 awg 20 amps
14 awg 15 amps
16 awg 7.5 amps

Thanks Edward, that makes sense. Appreciate the help!

[ndutton]

Although perfectly fine if you want to do it that way, a fuse for each gauge is certainly not common and could be considered excessive. Notice that your car isn't fused that way, it has a single fuse protecting the instrument cluster. Please consider whether or not you'll realistically attain greater protection with multiple fuses while at the same time know that every connection is another failure risk point.

[Graham]

Although perfectly fine if you want to do it that way, a fuse for each gauge is certainly not common and could be considered excessive. Notice that your car isn't fused that way, it has a single fuse protecting the instrument cluster. Please consider whether or not you'll realistically attain greater protection with multiple fuses while at the same time know that every connection is another failure risk point.

Thanks, good point. I just rewired it the same way it originally was. I'll reconsider this setup as I agree it may just be adding more points of failure.

[toddster]

I think the power (and illumination) wires to the gauges are usually daisy-chained, are they not? So there should be a single lead back to the bus. (Hard to tell on my boat, since so much stuff has been scabbed onto them over the years.)

[Graham]

I think the power (and illumination) wires to the gauges are usually daisy-chained, are they not? So there should be a single lead back to the bus. (Hard to tell on my boat, since so much stuff has been scabbed onto them over the years.)

I'm going to have a closer look on the weekend and confirm how it's wired. I do know there are 1 main fuse and 4 secondary fuses running the 4 gauges.

[toddster]

Photos might be interesting.

[joe_db]

Fusing each gauge would be rather unusual. I have one breaker for the entire ignition system and individual fuses for the blower, water pumps, and fuel pumps.