Fuses

[jared]

Hi Guys


I need some advice on fuses

I have just installed a switch panel with fuses to neaten the spaghetti mess that I had, but i cannot source the fuses recommended for the various electronics (glass vial fuses)

Lowrance LMS350A  recommends a 3 Amp fuse
Uniden MC1010   recommends a 6 Amp fuse
Navstar 220 ? 29MHZ  no instruction manual
Compass lighting Ritchie recommends 1 amp usage
Lights on the boat ?

The only fuses I can source are 5Amps, 10 Amps  that were used previously.

My question is are there fuses out there like 3 amps or do i just go for broke and put 5 amp fuses in like before.
What amps for lighting ie port starboard and central white light


Your thoughts would be appreciated

Cheers

 

[dugongboy]

Put the rated fuses in, look at places like A1 Radio or Midas??

 

[jared]

Hi

Surprise surprise I found the correct fuses at builders warehouse of all places , they had quite the selection

My next question is What amp fuse do I use for the lights or does it not really matter as long as the bulbs can handle the 13.8 volts max supply from the battery

Cheers

Jared

 

[kirk]

Hi the rule here is to use a low amp fuse as possible, using a higher amp fuse is dangerous as the fuse is supposed to break before the wire overheats and causes an on board fire. Not sure what wattage your nav lights are but check with whats on someone elses boat should be a guide at least.

hope someone else can be clearer.

 

[Fanie]

Fuses in a fuse box are actually rated to protect wiring, and not instruments or accessories.

Equipment should have their own fuse if designed to use a fuse, their rating has nothing to do with the fuses you use in the fusebox (or switch panel.

If your wires can handle 10A, then a 10A fuse should be used there, if the wires can handle 20A then a 20A fuse would be the right one, irrespective of how much the peripherals draw.

You also get different types of fuses. The correct type of fuse for protecting wiring should be a slow blow fuse, usually marked with a 'T' for 'trage' which is a German word for slow.

The reason for using a slow blow fuse is that some apps can draw more when they start up but in a short time the current drops to below the max, a bilge pump is such an app.

If a fast or extra fast fuse is used the bilge pump is almost sure to burn the fuse wire off each time. The wiring conducting the power to the bilge pump does not get damaged by these short overcurrent periods.

You have a better chance of finding the right type of fuses at electronic component resellers like Mantech, Protronix, Communica than at builders warehouse or hardware shops, simply because the component resellers specialize in components.

 

[Fanie]

What amps for lighting ie port starboard and central white light

Again the fuse should be chosen based on the current the wire can conduct I said that, but nowadays the old candescent lamps are all replaced with LED's simply because they draw a lot less current and they do not bust when a drop of water gets into contact with the lamp(s). LED's also last a lot longer sin in general is a lot more reliable.

There probably isn't a single reason you should not have LED lights instead of the old lights. If you still need a thumb suck on the current the nav lights should draw then lamps can be as much as 3A, with LED's maybe 400mA.

 

[benniejordaan]

Fanie wrote:

What amps for lighting ie port starboard and central white light

Again the fuse should be chosen based on the current the wire can conduct I said that, but nowadays the old candescent lamps are all replaced with LED's simply because they draw a lot less current and they do not bust when a drop of water gets into contact with the lamp(s). LED's also last a lot longer sin in general is a lot more reliable.

There probably isn't a single reason you should not have LED lights instead of the old lights. If you still need a thumb suck on the current the nav lights should draw then lamps can be as much as 3A, with LED's maybe 400mA.

Can you try get us a price for the LED light bulbs for port and stbd lamp. Last time I checked they were nearly R200 each. Compared to R2,50 for the standard ones. They are those long ones with a contact on both ends.