Thread: 20 Amp Fuse and 16 Gauge Wire ok for M1 PSU?

depends how far you are running it... 1 to 3 foot and itll be ok but at 4 foot you are dropping over half a volt from end to end, at 6 foot your losing nearly a volt, just through the wire, not recommended at all. (all figures calculated at a 15 amp load)

I am running it from the battery to under my seat. So then what gauge wire should I use and what amp fuse should I use?

I have the same question regarding wiring the M1-ATX. The PSU comes with 3 wires, all 18 gauge, but this won't be large enough to go from the battery to the Car PC under the passenger seat. I was thinking of 10 or 12 gauge wires and a 15amp fuse. The M1-ATX is fused protected, 10 amps, so is another fuse necessary? Or is the external fuse so you can safely run from the larger wire, i.e. 10/12/14, to the smaller 18 gauge wire? I haven't done any car wiring, but I know for house wiring 14ga is 15amps and 12ga is 20amps. What is the maximum amp value for 18ga and shouldn't that be the fuse value I use to prevent the smaller 18ga wire from over heating and causing a fire? It seems that 18 gauge is 10 amps max @10ft.

Also, the screen is powered via a molex connector to the PSU. Is a fuse needed for the screen as well or will the PSU fuse protect it?

@Epridaz: 20A fuse is too big for 16ga wire. 16ga should be fused around 8A. For a 15A load, 12 or 10ga would be a reasonable size, with a 20A fuse.

@Silentbob: 18ga is more like 5A max; it's ok for the very short leads going into your PSU, but not for any real length. Your other wire size to max amps is right on. Regardless of what you use, it's imperative you fuse at the battery - the PSU fuse will protect things downstream from it (like your screen) but not the wire from the batt.

Originally Posted by mushin

@Epridaz: 20A fuse is too big for 16ga wire. 16ga should be fused around 8A. For a 15A load, 12 or 10ga would be a reasonable size, with a 20A fuse.

@Silentbob: 18ga is more like 5A max; it's ok for the very short leads going into your PSU, but not for any real length. Your other wire size to max amps is right on. Regardless of what you use, it's imperative you fuse at the battery - the PSU fuse will protect things downstream from it (like your screen) but not the wire from the batt.

Yeah when I saw that 10 amps and it didn't seem right, but I thought "why would the M1-ATX come with 18gauge if it couldn't handle the amps so maybe that is right". So 12 gauge all the way to the PSU with a 15 amp fuse is the way I'll go. How many amps does the M1-ATX pull, don't want to use a fuse that is too small?

Originally Posted by Silentbob343

Yeah when I saw that 10 amps and it didn't seem right, but I thought "why would the M1-ATX come with 18gauge if it couldn't handle the amps so maybe that is right". So 12 gauge all the way to the PSU with a 15 amp fuse is the way I'll go. How many amps does the M1-ATX pull, don't want to use a fuse that is too small?

The M1's wiring is just for practical reasons; there is very little latency at short lengths so you can run less than a foot safely. The latency occurs when running at long distances. Otherwise you'll experience hard shutdowns when the car gets cranked and more effort from the PSU.