Alternator Fuse

The fuse protects your airplane bus from a malfunctioning alternator with shortened diodes, also, the wire is unfused hot from the battery side when the master relay is on. The fuse should be within the first inches of the master relay but because of its size, most people put the fuse on the firewall. If you have an EarthX battery, a full short anywhere along the thick hot wires will be detected anyway and the battery will go offline.

• You need an ANL fuse holder, e.g. from Steinair, for each alternator.
  • You will need 2 x MS24694-S56 AN3 flat head bolts to mount the fuse holder,e.g. pack of 25 from Spruce. It commonly says the holes of the fuse holder are for M6 bolts but the countersunk hole of the holder has 100 degree shoulders, while M6 bolts would have 90 degree flat heads.
• You need a fuse mostly equal to the rating of the alternator, but do check the alternator manal, i.e.
  • a 60A fuse, e.g. from Steinair, for the very commonly used B&C LX60 alternator (instead of the PlanePower one coming with Vans' FF kit).
  • a 40A fuse, e.g. from Steinair, for the very commonly used B&C BC410-H standby alternator.